CA1317863C - Solid phase assay employing capillary flow - Google Patents
Solid phase assay employing capillary flowInfo
- Publication number
- CA1317863C CA1317863C CA000562173A CA562173A CA1317863C CA 1317863 C CA1317863 C CA 1317863C CA 000562173 A CA000562173 A CA 000562173A CA 562173 A CA562173 A CA 562173A CA 1317863 C CA1317863 C CA 1317863C
- Authority
- CA
- Canada
- Prior art keywords
- tracer
- sample
- binder
- analyte
- assay
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
- G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
- G01N33/543—Immunoassay; Biospecific binding assay; Materials therefor with an insoluble carrier for immobilising immunochemicals
- G01N33/54366—Apparatus specially adapted for solid-phase testing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
- G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
- G01N33/5302—Apparatus specially adapted for immunological test procedures
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/90—Plate chromatography, e.g. thin layer or paper chromatography
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S436/00—Chemistry: analytical and immunological testing
- Y10S436/807—Apparatus included in process claim, e.g. physical support structures
Abstract
ABSTRACT OF THE DISCLOSURE
Test device and assay for determining analyte wherein tracer and sample may be simultaneously applied to different absorbent material portions both in capillary flow communication with an absorbent material portion having a binder supported thereon in a manner whereby sample contacts binder, prior to any substantial contact between sample and tracer or tracer and binder.
Test device and assay for determining analyte wherein tracer and sample may be simultaneously applied to different absorbent material portions both in capillary flow communication with an absorbent material portion having a binder supported thereon in a manner whereby sample contacts binder, prior to any substantial contact between sample and tracer or tracer and binder.
Description
SOLID P~SE ASSAY EMPLOYING CAPIL~U~ ~ 3 ~
This invention relates to an assay for an analyte-, and ,nore particularly to a solid phase assay.
In a solid phase assay, a binder specific for at least the ligand to be determined (analyte) is supported on a solid support, whereby, in the assay it is not necessary to employ -an additional ~gent for separating the bound and free phases formed in ~the assay.
There is known in the art assays for analytes wherein:
the tracer employed in the assay includes a particulate label, such as, for e~ample, a liposome which includes a detectable marker. Thus, for example, in such an assay, a binder specific for the analyte is supported -on a solid support, and the tracer is comprised of a ligand specific for the analyte, which ligand of the tracer is labeled with a particulate label, such as a liposome containing a detectable marker. In such an assay, the tracer is indirectly bound to the binder on the solid support by binding of the analyte to the binder and binding of the tracer to the analyte, whereby the presence and/or amount of analyte in a sample can be determined by detecting the presence and/or arnount of tracer, which is indirectly bound to the binder on the solid support.
The present invention is directed to improving assays for an analyte wherein the binder is present on a solid support, and in particular wherein the tracer employed in the assay is comprised of a ligand labeled with a particulate label.
In accordance with one aspect of the present invention, there is provided an assay for an analyte wherein there is employed in the ass~y a solid support having first, second and third portions, with the third portion of the solid support in~luding a binder for the analyte, wiSh the sample being applied to the first portion of the solid support and tracer to the second portion of the solid support. The first and second portions of the solid support are in capillary flow commJnicatlon with the third portion of the solid support to provide for capillary flow of the sample and tracer for cont&ct with the binderO
In a preferred embodiment, the sample and tracer are caused to flow to the binder in a manner such that the sample contacts the binder, prior to substantial contact of the tracer with either of the sample or binder.
The tracer is a !igand labeIed with a detectable label, preferably a particulate label, with the ligand portion of the tracer capable of being bound directly or indirectly to analyte which is bound to the supported binder.
The amount and/or presence of analyte in a sample may be determined by detecting the presence andtor amount of tracer bound to the analyte, which analyte is bound to the binder in the third portion of the solid support.
- ln accordance with another aspect of the present invention, there is provided a solid support having a first portion for receiving a tracer, a second portion for receiving a sample and a third portion which includes a binder for analyte in the sample wherein the first and second portions are both in capillary flow cornmunication with the third portion to provide for flow and contact between ~he tracer, sample and binder. ln a preferred embodiment, the capillary flow comnunicàtion is such that there is contact between sample and binder prior to r~
substantial contact of the tracer with either the sample or ~
oO
the binder. r_ In the preferred embodiment, the tracer and sample m~y be applied to separate portions of the solid support, without prior contact between the sample and the binder, with the sample and tracer flowing by capillary action to the third portion of the support9 which contains supported binder for the analyte, in a manner such that the sample contacts the binder, prior to any substantial cont~ct between the tracer and either of the sample or the binder9 whereby 8 SO called "sandwich assay" is accomplished~ in the so called "forwardl' or "sequential" mode, without the necessity of separately directly applying a sample and tracer to the portion of the solid support which contains the supported binder.
The solid support includes an absorbent material capable of transporting a liquid by capillary flow. In this manner, the tracer and sample which are applied to separate portions of the support are transported by capillarity to the portion of the support which includes immobilized binder. As hereinabove indicated, the portion of the support to which the sample is applied, and the portion to which the tracer is applied are both in capillary flow communication with the portion of the support containing the immobilized binder in a manner such that the sample contacts the binder prior to substantial contact of the tracer with either the sample or the supported binder. Such a result may be achieved by appropriately arranging the respective portions of the support to which the sample and tracer are applied, with respect to the portion of the support to which the binder is applied, in a manner such that the path of travel of the sample to the binder is shorter than the path of travel of the tracer to the binder. In a preferred embodiment, the tracer has a detectable particlllate label whereby the tracer, having a particulate label, moves at ~ slower rate than the sample, and such difference in flow rate, as well as any difference in flow path aids in providing for contact of the sample with the binder, prior to contact of the tracer with either the sample or the binder. It is to be understood, however, that the length of the flow p~th of the tracer r~y be the same as or less than the length of the flow path of the sample to the binder in that it is possible to provide for prior contact of the sample with the binder by means other than the length of the respective flow paths.
Thus, for example, a blocking agent may be added to the portion of the S3 lid support which provides a capillary flow path between the portion of the support to which the tracer is applied, and the portion of the support which includes the binder to thereby impede the flow of the tracer to the binder. Such a blocking agent is a material which inhibits wetting of the support, with such inhibition of wetting reducing the rate at which the liquid containing the tr~cer flows by capillarity to the portion of the support including the supported binder. As representative examples of such blocking agents, there may be rnentioned:
bovine serum albumin, alone, or in combination with glucose; other proteinacious matter alonej or in combination with a sugar such as for example a fish gelatin obtained from a fresh water fish in combination with sucrose; and the like. The selection of a suitable blocking agent which inhibits wetting of the absorbent material to reduce the rate of flow should be apparent to those skilled in ~he art from the teachings herein.
As further alternatives, the respective rates of flow may be controlled by the width of the respective flow paths or the area to which tracer and sample are applied. o It is also to be understood that a combination of various me~ns may be employed to insure that the sample applied to the solid support reaches the binder, prior to contact between the tracer and the binder, such as, for example, a combination of respective lengths of flow path and the use of a blocking agent to inhibit the flow of the tracer.
Applicant has also found that substantial contact between the tracer and the sample, prior to contacting of the binder with the sample, should also be prevented.
Applicant has found that prior contact between the sample and the tracer, on the solid support, may r~educe sensitivity and/or may cause agglutination of the tracer in the preferred embodiment where the label of the tracer is a particulate label, whereby the sample and the tracer are applied to the separate portions of the solid support, which are in capillary flow commnication with the portion of the support containing the binder, in a manner such that substantial contact between the tracer and the sample is avoided, prior to contacting of the sample with the binder.
Such a result may be achieved by causing the sample to flow to the bindery ahead o-f the tracer, as hereinabove .
indicated. In addition, prevention of contact between sample and tracer prior to contact with the binder mav be further assured by providing separate paths of flow for each o the sample and tracer. 1 31 7863 Thus, the solid support is constructed andior the portions to which the tracer and sample are applied are ~rranged in a mQnner such that both the tracer and the sample flow by capillary action to the por~ion of the - support which includes the binder and in a manner such that the sample contacts the binder prior to -any substantial contact of the tracer with either the binder or the sampleO
Such a result rnay be achieved by arr~nging the respective flow paths and/or flow ~rates of the sample and tracer on the support to achieve such a result, whereby both the sarnple and tracer may be applied to the support without the necessity of separately directly adding both sample and tracer to the portion of the support containing the immobilized binder.
At least the portion of the support which provides the capillary flow paths for the tracer and sample is formed from a suitable absorbent material which is capable of transporting a liquid by capillarity. As representative examples of such materials, there may be mentioned: glass fiber, cellulose, nylon, crosslinked dextran, various ~chromatographic papers, nitrocellulose, etc. The selection of a suitable material is deerned to be within the scope of those skilled in the art from the teachings herein.
In accordance with a particularly preferred embodiment, the portion of the support which includes the binder (third portion) is employed as the test area for determining bound tracer. In accordance with - the particula.ly preferred embodiment, at least the third portion of the support is formed from a materiRl which is capable of transporting material by ~apillary flow through c~
such third portion and which has a surface area capable of r_ supporting the binder in a concentration of at least 1 ug/cm2 (most generally in a concentration of at Ieast 10 ug /cm2 ) .
Although nitrocellulose is a preferred material, it is to be understood that other materials having Q surface area sufficient for supporting the -binder in a concentration as hereinabove described may also be employed for producing such solid supports.
In accordance with a particularly preferred embodiment, the pore size of the solid support is such that the preferred tracer (ligand labeled with a particulate label), when bound directly or indirectly to the analyte bound to the binder, remains on the surface of the support.
As should be apparent, portions of the support (or all of the support~ in addition to the portion of the support employed for supporting the binder may be formed from a material having a surface area capable of supporting the binder in the hereinabove described concentrations.
The type of binder which is used in the assay is dependent upon the analyte to be assayed. As known in the art, the binder which is supported may be an antibody including monoclonal antibodies, an antigen, a protein specific for the material to be bound or a naturally occurring binder. If the assay is for an antibody, then the binder may be, for example, an antigen or an antibody which is specific for the antibody to be assayed. If the analyte is an antigen ~an antigen having more than one determinant site), then the binder may be an antibody or naturally occurring binder which is specific ~or the antigen to be assayed. 1 31 7863 The selection of a suitable binder for support on the solid substrate is deemed to be within the scope of those skilled in the art from the teachings herein.
The ligand which is labeled for use as a tracer in the assay of the present invention is dependent upon the analyte to be assayed, as well as the assay procedure.
Thus9 for example, the ligand may be specific for the analyte, whereby the tracer would be bound directly to the analyte which is bound to the supported binder.
Alternatively, the ligand employed in forming the tracer may be one which is capable of being bound to an analyte specific for the analyte; e.g., the ligand tracer may bë
IgG labeled with a particulate label, whereby the tracer is indirectly bound to the anelyte through an antibody bound to the analyte. As should be apparent, the ligand used in producing the tracer may be an antigen or an antibody or a naturally occurring substance which is specifically bound by the analyte. The selection of a suitable li~and is within the scope of those skilled in the art.
As hereinabove indicated, in producing the tracer, the ligand is prefer~bly labeled with a particulate label, which includes a detectable marker. In accordance with a preferred embodiment, the particulate label is visible. A
preferred particulate label is a SRC, which includes a dye or other colored salbstance as a marker, whereby the tracer, when used in the assay, is visible without destruction of the sac to release the colored substance.
The sac which is used to label the ligand for producing a tracer may be any one of a wide variety of sacs, including but not limited to intact erythrocytes, erythrocyte ghosts, liposomes (single walled [sometimes oc~
called vesicles] or multilamellar), polymer microcapsules (for example, those made by coascervation, or interfacial polymerization~, etc.
Erythrocyte ghosts are known in the art and are prepared by suspending erythrocyte cells in a solution of substantially lower osmolarity~ The ghosts are "resealed"
in an aqueous solution including the marker whereby the ghosts include the m~rker in the interior thereof~ Such procedures are known in the art and the resealing solution of appropriate osmolarity generally includes, in addition to the marker, alkali and alkaline earth metal halides and coenzyme; e.g., adenosine triphosphate. The preparation of ghosts, as sacs, is disclosed, for example, by D'Orazio et al, Analxtical Chemistry, Vol. 49, No. 13, pages 2083-86 -(Nov. 1977).
Polymer microcapsules are also produced by procedures known in the art except that the solution in which the microcapsules are formed also includes the marker whereby the interior of the polymer microcapsule includes the marker. The preparation of such microcapsules is disclosed ~for example in Microcenca~sulation _ Process and Applications, edited by Jan E. Vandegger (Plenum Press 1974).
As known in the art, liposome can be prepared from a wide variety of lipids, including phospholipids, glycolipids3 steroids, relatively long chain alkyl esters;
e.g., alkyl phosphates, fatty acid esters; e.g., lecithin, fatty amines and the like. A mixture of fatty m~terials may be employed, such as a combination of neutral steroid, _g _ a charged amphiphile and a phospholipid. As illustrative examples o~ phospholipids, there m~y be mentioned lecithin, sphingomyelin, dipalmitoyl, lecithin, and the like. As representative s~eroids, there may be mentioned cholesterol, cholestQnol, lanesterol, and the like. As representative exQmples of chsrged amphiphili~ compounds, which genernlly contain ~rom la to 30 c~rbon ~toms, there m~y be mentioned mono or dialkyl phosphate ester or an alkyl~mine; e.g., dicetyl phosphate, stearyl amine, hexadecyl amine, dilauryl phosphate, and the like.
The liposome sacs are prep~red in an aqueous solution . including the marker whereby the sacs will include the t m~rker in the interior thereof. The liposome sacs are easily prepared by vigorous agitation in the solution, followed by removal of marker from the exterior of the sac.
Further details with respect to the prep~ration of - lipvsomes are set forth in U.S. Patent NP. 4,3~2,826 and PCT International Publication No. WO80/01515.
¦ As hereinabove indicated, the marker prefer~bly included in the sac is a dye or some other material which is ~isible, without Iysing of the sacs.
The tracer comprised of ligand and particulate label m~ also be produced by labeling the ligand with an aqueous dispersion of a hydrophobic dye or pigment, or of polymer nuclei coated with such a dye or pigment. Such labels are described in more detail in U.SI Patent No. 4,373,93~, which issued on February 15~ 1983. The tracers produced in accordance with such p~tent may also be employed ~s tracers in the present invention.
As indicated in the aforesaid patent, the co~ored ~ o organic compounds which are used as labels are in the form ~
of a hydrophobic sol, which hydrophobic organic dyes or pigments are insoluble in wuter or soluble only to a very limited extent. As indicated in t~e patent, particles of the aqueous dispersion o~ a hyrdrophobic dye or pigment, or of polymeric nuclei coated with such a dye or pigment have a particle size of at least 5 nm, ~nd preferably at least 10 nm.
Such tracers which are labeled with the hydrophobic dye or pigment or with a polymer nuclei coated with such dye or pigment, are visible tracers when used in the assay in accordance with the present invention.
The visible particulate label may be visible polymer particles, such as colored polystyrene particles, preferably of spherical shape.
As representative examples of other particulate labels which may be employed in producing a tracer for use in the assay of the present invention, in which the tracer would be visible, there may be mentioned; ferritin, phycoerythrins o~r other phycobili-proteins; precipitated or insoluble metals or alloys; fungal, algal, or bacterial pigments or derivatives such as bacterial chlorophylls;
plant materials or derivatives and the like.
The ligand may be labeled with the particulate label so as to produce a tracer for use in the invention by procedures generally known in the art, with the procedure which is used being dependent upon the ligand -and the particulate label which is employed. Such techniques include absorption, covalent coupling, derivatization or activation, and the like. In producing a tracer wherein the ligand is labeled with a sac, the sac may be produced ~ O
from a component which has been derivatized with Q ligflnd, 00 whereby the sac, when produced, is sensitized with the ligand. In another procedure, the sac including the marker may be initialy formed, followed by sensitizing the sac with ligand by procedures known in ~he art.
Thus, the preferred tracer is comprised of a ligand and a particulate label (solid or solid-like, as opposed to non-solid labels, such as radiostopes, enzy~es and various fluorescent materials), and the particulate label preferably provides a tracer which is visible under the assay conditions so that the presence and/or amount of analyte may be determined without further treatment and without the use of instrumentation; e.g., by use of a liposome containing a dye as the particulate label.
The solid substance employed in the assay is preferably in sheet form, with the substrate, in sheet form, generally being in the form of a card, a test strip or dipstick, etc. It is to be understood, however, that other forms are also within the spirit and scope of the invention.
The binder is supported on the test ares of the solid substrate by applying a solution of the binder to a defined area of the test substrste; such as, for example, in the form of a spot, which can be located in a marked area, e.g., square or circle, on the substrate. Particularly good results have been obtained when the binder is applied to the test area as a spot having a diameter of from 3 to 5 mm. The concentration of the binder plsced in the defined test area will vary depending upon the assay to be perfor~ed; however, the binder is generally present in a concentration of at least 1 ug/cm2 (most generally st least lo ug/cm2.) 1 31 7863 After application of the binder to one or more test areas on the substra~e, the residu~l binding capRcity of the test substance is saturated or blocked by treatment of the test substrate with one or more types of proteins which do not specifically bind the materials to be employed in the assay. Thus9 for example, the residual binding capacity of the substrate may be blocked so as to prevent non-specific binding by the use of bovine serum albumin.
The techniques for preventing non-specific binding are generally known in the art, and such techniques are also generally applicable to preventing non-specific binding in the assay of the present invention.
In accordance with the present invention, the first portion of the solid support rnay be provided with the tracer, during the assay procedure, or the solid support may be produced with the tracer on the first portion thereof. In the latter case, the tracer is supported on the support in a manner such that upon wetting of the first portion, the tracer flows by capillarity to the third portion of the solid suport. Thus, for example, the tracer may be absorbed on the soli-d support, in the first portion thereof, whereby upon wetting of the first portion during the assay, the tracer flows by capillarity to the third portion of the solid support which includes the binder, as hereinabove described.
The invention will be further described with respect to embodiments thereof illustrated in the accompanying drawings wherein: ~
Referring to Figure 1, there is shown a test card 10, r~
which is generelly comprised of an upper card member 11 and a lower card member 12. The upper card member 11 is r~
provided with A tracer loading port 13, sample loading port __ 14 and a test view window or port 15.. A test sheet 16~
preferably nitrocellulose9 is placed between the upper and lower csrd members 11 and 12, respectively, with Q portion Qf the nitrocellulose being vi~ible through test port 15.
At least a portion of the sheet 16 which is viewable through window lS includes a binder specific for the analyte to be assayed and defines ~ test area. A first strip of absorbent materiAl 17 is placed between the upper and lower card members 11 and 12 and extends between tracer loading port 13 and view window 15 with the aborbent material 17 being in contact with test sheet 16. A second strip of absorbent material 18 is placed between the upper and lower card members 11 and 12 and extends between sample loading port 14 and view window 15, with the absorbent material 18 being in contact with the test sheet 16. As shown, the strips 17 and 18 are separ~te and distinct from each other and provide separate capillary flow paths from each of ports 13 and }4 to view window 15. Strips 17 and 18 may be formed, for example, from glass fiber.
As particularly shown, the sample loading port 14 is closer to the viewing window 15 than the tracer loading port 13, whereby the capillary flow path between ports 14 and 15 is shorter than the capillary flow path between ports 13 and 15. In addition, the strip 17 may be treated with a material to reduce the capillary rate of flow.
A p-iece of material 21 having a high liquid absorption capacity, such as blotting paper, is positioned between upper and lower card member l~ and 12 in contact with test sheet 18 to receive and store test materialO
In an assRy, a sample to be assayed is applied through test port 14 and tr~cer is applied through test port 13.
The sample flows to the test sheet 16 through strip 18 and the tracer- flows to test sheet 16 through strip 17. As hereinabove indica~ed, the flow paths and/or strips ~re constructed in a manner such that the sample contacts the binder on the test sheet 16, prior to contact of the tracer with either the binder or sampleO The tracer may then be determined through test window 15.
The presence and/or amount of analyte present in the sample may be determined by the presence and/or amount of tracer, as determined through window 15 of the card 10.
ln accordance with a preferred embodiment, as hereinabove described, by using an appropriate material as sheet 16 (for example, nitrocellulose) and a visible particulate label (such as a liposome including Q SUi table dye), it is possible to determine tracer through window 15 without destruction of the liposome.
Although the embodiment has been described with respect to the use of a tracer which includes a visible particulate label, it is to be understood that other detectable labels may be employed within the spirit and scope of the invention; e.g., an enzyme label; a chromogen label (fluorescent and/or absorbing dye), etc. ln such cases, it may be necessary to add an additional substance in order to detect the label in view window 15; e.g. t in the case of an enzyme label, a substrate to produce detectable eolor in the view window.
It is also possible to provide a view window over the material 21 in place o~ or in con~unction with the view window 15. In this m~nner~ tracer wh~ch hss not been bound in test sheet portion 16 may be de~ermined. The presence and/or amount of tracer In portion 21 may be employed to determine analyte ~lone ~nd/or in con~unction with the presence and/or ~mount or ~nalyte in portion 16.
The invention will be further described witb respect to the following ex~mple; however, the scope of the invention is not to be limited thereby:
EXA~PLE
___ A reaction c~rd 10 was constructed using two plastic cards 11 and 12. The cards were made of polypropylene with a thickness of approximately 0.03 inches. The top card has three holes which include a view window 15, liposome trscer loading port 13, ~nd a s~mple lo~ding port 14. The view Ir window has 8 diameter of approximately 12.0 mm while the loading ports ~re 6maller (4.0 mm).
jThe first step in construction W8~ to place double . *
.;.stick adhesive (3,M Type 960) over the entire card.
Nitrocellulose ~5.0 ~ S~S) with the capture ~ntibody was ¦~ttached to the card as test sheet 16. Sheet 1~ was spotted with 3 Ol of affinity purified r~bbit anti-Group A
antigen and then blocked with 3% bovine serum :
albumin. The antibody portion is below window 15.
Blotting paper 21 (Gelman 51334) was placed on the card such that the paper was in cont~ct with the nitrocellulose.
The window and lo~ding ports were punched ou~ of a second card. Adhesive was placed over the holes and excess Adhesive was removed from the holss. This process led to a card that had adhesive completely surroun~ing the ports.
* Trademark~ -16 1 3t 7~63 Next, str ips of glass f iber (Whatman ~F/A3 17 ~nd 18 were pl~ced sn the card such that they m~de a connection from the lo~ding ports to the ~iew window. Strip 18 is treated with a 3% B5A solution.
Detector lipsomes packed with sulfo-rhodamine dye were prepared by the method outljned in O'C~nnell et al. ~CIin.
. Chem. 31:1424 E198s~). They were covalently coupled to affinity purified rabbit anti-Group A ~ 2~ 2 antigen.
Group A S~reptococcus organisms were harvested from culture plates, washed with saline (0.9% NaC1~, ~nd adjusted to 1 x 109 orgsnisms/ml. An aliquot (0.1 mlj containing 1 x 108 organisms w~s subjected to the miero nitrous acid extractlon method for exposing the Group A
carbohydrate antigen. This method consists of mixing 0.3 ml of 0.1 M HCl with 40 ul of 4~ NaNO2., adding this to the Stre~tococcus org~nisms and, ~fter 3 minutes, neturalizing : with 40 ul of 1~ rris base. To facilitate the extraction, the HC1 and the subsequent diluting fluid contain 0.1%
i Tween-20 non-ionic detergent.
I A reservolr was attached to the device to assure that all the sample (0,3 ml) could be added at one time.
Immediately after addition of the sample through port 14 the liposome tracer was added to the tracer port i3. No other m~nipulations were re~uired. Within five minutes a specific signal ~t the c~pture antibody spot. (Window 153 could be seen at Q sensitiYity level equivalent to 1 X 106 CF~/ml.
~ he present invention is advantageous in that it is possible to provid~ 8 sandwi~h ass~y wi~hout separate 7~
* Trademark ~17-13~7863 incubation und wash steps, and which has the requisite sensitivityO
These and other advanteges should be spparent to those skilled in the art.
Numerous modifications and veriations of the present invention are possible in light of the above teachings and, therefore9 within the seope of the appended claims, the invention may be practised otherwise than as particularly described.
This invention relates to an assay for an analyte-, and ,nore particularly to a solid phase assay.
In a solid phase assay, a binder specific for at least the ligand to be determined (analyte) is supported on a solid support, whereby, in the assay it is not necessary to employ -an additional ~gent for separating the bound and free phases formed in ~the assay.
There is known in the art assays for analytes wherein:
the tracer employed in the assay includes a particulate label, such as, for e~ample, a liposome which includes a detectable marker. Thus, for example, in such an assay, a binder specific for the analyte is supported -on a solid support, and the tracer is comprised of a ligand specific for the analyte, which ligand of the tracer is labeled with a particulate label, such as a liposome containing a detectable marker. In such an assay, the tracer is indirectly bound to the binder on the solid support by binding of the analyte to the binder and binding of the tracer to the analyte, whereby the presence and/or amount of analyte in a sample can be determined by detecting the presence and/or arnount of tracer, which is indirectly bound to the binder on the solid support.
The present invention is directed to improving assays for an analyte wherein the binder is present on a solid support, and in particular wherein the tracer employed in the assay is comprised of a ligand labeled with a particulate label.
In accordance with one aspect of the present invention, there is provided an assay for an analyte wherein there is employed in the ass~y a solid support having first, second and third portions, with the third portion of the solid support in~luding a binder for the analyte, wiSh the sample being applied to the first portion of the solid support and tracer to the second portion of the solid support. The first and second portions of the solid support are in capillary flow commJnicatlon with the third portion of the solid support to provide for capillary flow of the sample and tracer for cont&ct with the binderO
In a preferred embodiment, the sample and tracer are caused to flow to the binder in a manner such that the sample contacts the binder, prior to substantial contact of the tracer with either of the sample or binder.
The tracer is a !igand labeIed with a detectable label, preferably a particulate label, with the ligand portion of the tracer capable of being bound directly or indirectly to analyte which is bound to the supported binder.
The amount and/or presence of analyte in a sample may be determined by detecting the presence andtor amount of tracer bound to the analyte, which analyte is bound to the binder in the third portion of the solid support.
- ln accordance with another aspect of the present invention, there is provided a solid support having a first portion for receiving a tracer, a second portion for receiving a sample and a third portion which includes a binder for analyte in the sample wherein the first and second portions are both in capillary flow cornmunication with the third portion to provide for flow and contact between ~he tracer, sample and binder. ln a preferred embodiment, the capillary flow comnunicàtion is such that there is contact between sample and binder prior to r~
substantial contact of the tracer with either the sample or ~
oO
the binder. r_ In the preferred embodiment, the tracer and sample m~y be applied to separate portions of the solid support, without prior contact between the sample and the binder, with the sample and tracer flowing by capillary action to the third portion of the support9 which contains supported binder for the analyte, in a manner such that the sample contacts the binder, prior to any substantial cont~ct between the tracer and either of the sample or the binder9 whereby 8 SO called "sandwich assay" is accomplished~ in the so called "forwardl' or "sequential" mode, without the necessity of separately directly applying a sample and tracer to the portion of the solid support which contains the supported binder.
The solid support includes an absorbent material capable of transporting a liquid by capillary flow. In this manner, the tracer and sample which are applied to separate portions of the support are transported by capillarity to the portion of the support which includes immobilized binder. As hereinabove indicated, the portion of the support to which the sample is applied, and the portion to which the tracer is applied are both in capillary flow communication with the portion of the support containing the immobilized binder in a manner such that the sample contacts the binder prior to substantial contact of the tracer with either the sample or the supported binder. Such a result may be achieved by appropriately arranging the respective portions of the support to which the sample and tracer are applied, with respect to the portion of the support to which the binder is applied, in a manner such that the path of travel of the sample to the binder is shorter than the path of travel of the tracer to the binder. In a preferred embodiment, the tracer has a detectable particlllate label whereby the tracer, having a particulate label, moves at ~ slower rate than the sample, and such difference in flow rate, as well as any difference in flow path aids in providing for contact of the sample with the binder, prior to contact of the tracer with either the sample or the binder. It is to be understood, however, that the length of the flow p~th of the tracer r~y be the same as or less than the length of the flow path of the sample to the binder in that it is possible to provide for prior contact of the sample with the binder by means other than the length of the respective flow paths.
Thus, for example, a blocking agent may be added to the portion of the S3 lid support which provides a capillary flow path between the portion of the support to which the tracer is applied, and the portion of the support which includes the binder to thereby impede the flow of the tracer to the binder. Such a blocking agent is a material which inhibits wetting of the support, with such inhibition of wetting reducing the rate at which the liquid containing the tr~cer flows by capillarity to the portion of the support including the supported binder. As representative examples of such blocking agents, there may be rnentioned:
bovine serum albumin, alone, or in combination with glucose; other proteinacious matter alonej or in combination with a sugar such as for example a fish gelatin obtained from a fresh water fish in combination with sucrose; and the like. The selection of a suitable blocking agent which inhibits wetting of the absorbent material to reduce the rate of flow should be apparent to those skilled in ~he art from the teachings herein.
As further alternatives, the respective rates of flow may be controlled by the width of the respective flow paths or the area to which tracer and sample are applied. o It is also to be understood that a combination of various me~ns may be employed to insure that the sample applied to the solid support reaches the binder, prior to contact between the tracer and the binder, such as, for example, a combination of respective lengths of flow path and the use of a blocking agent to inhibit the flow of the tracer.
Applicant has also found that substantial contact between the tracer and the sample, prior to contacting of the binder with the sample, should also be prevented.
Applicant has found that prior contact between the sample and the tracer, on the solid support, may r~educe sensitivity and/or may cause agglutination of the tracer in the preferred embodiment where the label of the tracer is a particulate label, whereby the sample and the tracer are applied to the separate portions of the solid support, which are in capillary flow commnication with the portion of the support containing the binder, in a manner such that substantial contact between the tracer and the sample is avoided, prior to contacting of the sample with the binder.
Such a result may be achieved by causing the sample to flow to the bindery ahead o-f the tracer, as hereinabove .
indicated. In addition, prevention of contact between sample and tracer prior to contact with the binder mav be further assured by providing separate paths of flow for each o the sample and tracer. 1 31 7863 Thus, the solid support is constructed andior the portions to which the tracer and sample are applied are ~rranged in a mQnner such that both the tracer and the sample flow by capillary action to the por~ion of the - support which includes the binder and in a manner such that the sample contacts the binder prior to -any substantial contact of the tracer with either the binder or the sampleO
Such a result rnay be achieved by arr~nging the respective flow paths and/or flow ~rates of the sample and tracer on the support to achieve such a result, whereby both the sarnple and tracer may be applied to the support without the necessity of separately directly adding both sample and tracer to the portion of the support containing the immobilized binder.
At least the portion of the support which provides the capillary flow paths for the tracer and sample is formed from a suitable absorbent material which is capable of transporting a liquid by capillarity. As representative examples of such materials, there may be mentioned: glass fiber, cellulose, nylon, crosslinked dextran, various ~chromatographic papers, nitrocellulose, etc. The selection of a suitable material is deerned to be within the scope of those skilled in the art from the teachings herein.
In accordance with a particularly preferred embodiment, the portion of the support which includes the binder (third portion) is employed as the test area for determining bound tracer. In accordance with - the particula.ly preferred embodiment, at least the third portion of the support is formed from a materiRl which is capable of transporting material by ~apillary flow through c~
such third portion and which has a surface area capable of r_ supporting the binder in a concentration of at least 1 ug/cm2 (most generally in a concentration of at Ieast 10 ug /cm2 ) .
Although nitrocellulose is a preferred material, it is to be understood that other materials having Q surface area sufficient for supporting the -binder in a concentration as hereinabove described may also be employed for producing such solid supports.
In accordance with a particularly preferred embodiment, the pore size of the solid support is such that the preferred tracer (ligand labeled with a particulate label), when bound directly or indirectly to the analyte bound to the binder, remains on the surface of the support.
As should be apparent, portions of the support (or all of the support~ in addition to the portion of the support employed for supporting the binder may be formed from a material having a surface area capable of supporting the binder in the hereinabove described concentrations.
The type of binder which is used in the assay is dependent upon the analyte to be assayed. As known in the art, the binder which is supported may be an antibody including monoclonal antibodies, an antigen, a protein specific for the material to be bound or a naturally occurring binder. If the assay is for an antibody, then the binder may be, for example, an antigen or an antibody which is specific for the antibody to be assayed. If the analyte is an antigen ~an antigen having more than one determinant site), then the binder may be an antibody or naturally occurring binder which is specific ~or the antigen to be assayed. 1 31 7863 The selection of a suitable binder for support on the solid substrate is deemed to be within the scope of those skilled in the art from the teachings herein.
The ligand which is labeled for use as a tracer in the assay of the present invention is dependent upon the analyte to be assayed, as well as the assay procedure.
Thus9 for example, the ligand may be specific for the analyte, whereby the tracer would be bound directly to the analyte which is bound to the supported binder.
Alternatively, the ligand employed in forming the tracer may be one which is capable of being bound to an analyte specific for the analyte; e.g., the ligand tracer may bë
IgG labeled with a particulate label, whereby the tracer is indirectly bound to the anelyte through an antibody bound to the analyte. As should be apparent, the ligand used in producing the tracer may be an antigen or an antibody or a naturally occurring substance which is specifically bound by the analyte. The selection of a suitable li~and is within the scope of those skilled in the art.
As hereinabove indicated, in producing the tracer, the ligand is prefer~bly labeled with a particulate label, which includes a detectable marker. In accordance with a preferred embodiment, the particulate label is visible. A
preferred particulate label is a SRC, which includes a dye or other colored salbstance as a marker, whereby the tracer, when used in the assay, is visible without destruction of the sac to release the colored substance.
The sac which is used to label the ligand for producing a tracer may be any one of a wide variety of sacs, including but not limited to intact erythrocytes, erythrocyte ghosts, liposomes (single walled [sometimes oc~
called vesicles] or multilamellar), polymer microcapsules (for example, those made by coascervation, or interfacial polymerization~, etc.
Erythrocyte ghosts are known in the art and are prepared by suspending erythrocyte cells in a solution of substantially lower osmolarity~ The ghosts are "resealed"
in an aqueous solution including the marker whereby the ghosts include the m~rker in the interior thereof~ Such procedures are known in the art and the resealing solution of appropriate osmolarity generally includes, in addition to the marker, alkali and alkaline earth metal halides and coenzyme; e.g., adenosine triphosphate. The preparation of ghosts, as sacs, is disclosed, for example, by D'Orazio et al, Analxtical Chemistry, Vol. 49, No. 13, pages 2083-86 -(Nov. 1977).
Polymer microcapsules are also produced by procedures known in the art except that the solution in which the microcapsules are formed also includes the marker whereby the interior of the polymer microcapsule includes the marker. The preparation of such microcapsules is disclosed ~for example in Microcenca~sulation _ Process and Applications, edited by Jan E. Vandegger (Plenum Press 1974).
As known in the art, liposome can be prepared from a wide variety of lipids, including phospholipids, glycolipids3 steroids, relatively long chain alkyl esters;
e.g., alkyl phosphates, fatty acid esters; e.g., lecithin, fatty amines and the like. A mixture of fatty m~terials may be employed, such as a combination of neutral steroid, _g _ a charged amphiphile and a phospholipid. As illustrative examples o~ phospholipids, there m~y be mentioned lecithin, sphingomyelin, dipalmitoyl, lecithin, and the like. As representative s~eroids, there may be mentioned cholesterol, cholestQnol, lanesterol, and the like. As representative exQmples of chsrged amphiphili~ compounds, which genernlly contain ~rom la to 30 c~rbon ~toms, there m~y be mentioned mono or dialkyl phosphate ester or an alkyl~mine; e.g., dicetyl phosphate, stearyl amine, hexadecyl amine, dilauryl phosphate, and the like.
The liposome sacs are prep~red in an aqueous solution . including the marker whereby the sacs will include the t m~rker in the interior thereof. The liposome sacs are easily prepared by vigorous agitation in the solution, followed by removal of marker from the exterior of the sac.
Further details with respect to the prep~ration of - lipvsomes are set forth in U.S. Patent NP. 4,3~2,826 and PCT International Publication No. WO80/01515.
¦ As hereinabove indicated, the marker prefer~bly included in the sac is a dye or some other material which is ~isible, without Iysing of the sacs.
The tracer comprised of ligand and particulate label m~ also be produced by labeling the ligand with an aqueous dispersion of a hydrophobic dye or pigment, or of polymer nuclei coated with such a dye or pigment. Such labels are described in more detail in U.SI Patent No. 4,373,93~, which issued on February 15~ 1983. The tracers produced in accordance with such p~tent may also be employed ~s tracers in the present invention.
As indicated in the aforesaid patent, the co~ored ~ o organic compounds which are used as labels are in the form ~
of a hydrophobic sol, which hydrophobic organic dyes or pigments are insoluble in wuter or soluble only to a very limited extent. As indicated in t~e patent, particles of the aqueous dispersion o~ a hyrdrophobic dye or pigment, or of polymeric nuclei coated with such a dye or pigment have a particle size of at least 5 nm, ~nd preferably at least 10 nm.
Such tracers which are labeled with the hydrophobic dye or pigment or with a polymer nuclei coated with such dye or pigment, are visible tracers when used in the assay in accordance with the present invention.
The visible particulate label may be visible polymer particles, such as colored polystyrene particles, preferably of spherical shape.
As representative examples of other particulate labels which may be employed in producing a tracer for use in the assay of the present invention, in which the tracer would be visible, there may be mentioned; ferritin, phycoerythrins o~r other phycobili-proteins; precipitated or insoluble metals or alloys; fungal, algal, or bacterial pigments or derivatives such as bacterial chlorophylls;
plant materials or derivatives and the like.
The ligand may be labeled with the particulate label so as to produce a tracer for use in the invention by procedures generally known in the art, with the procedure which is used being dependent upon the ligand -and the particulate label which is employed. Such techniques include absorption, covalent coupling, derivatization or activation, and the like. In producing a tracer wherein the ligand is labeled with a sac, the sac may be produced ~ O
from a component which has been derivatized with Q ligflnd, 00 whereby the sac, when produced, is sensitized with the ligand. In another procedure, the sac including the marker may be initialy formed, followed by sensitizing the sac with ligand by procedures known in ~he art.
Thus, the preferred tracer is comprised of a ligand and a particulate label (solid or solid-like, as opposed to non-solid labels, such as radiostopes, enzy~es and various fluorescent materials), and the particulate label preferably provides a tracer which is visible under the assay conditions so that the presence and/or amount of analyte may be determined without further treatment and without the use of instrumentation; e.g., by use of a liposome containing a dye as the particulate label.
The solid substance employed in the assay is preferably in sheet form, with the substrate, in sheet form, generally being in the form of a card, a test strip or dipstick, etc. It is to be understood, however, that other forms are also within the spirit and scope of the invention.
The binder is supported on the test ares of the solid substrate by applying a solution of the binder to a defined area of the test substrste; such as, for example, in the form of a spot, which can be located in a marked area, e.g., square or circle, on the substrate. Particularly good results have been obtained when the binder is applied to the test area as a spot having a diameter of from 3 to 5 mm. The concentration of the binder plsced in the defined test area will vary depending upon the assay to be perfor~ed; however, the binder is generally present in a concentration of at least 1 ug/cm2 (most generally st least lo ug/cm2.) 1 31 7863 After application of the binder to one or more test areas on the substra~e, the residu~l binding capRcity of the test substance is saturated or blocked by treatment of the test substrate with one or more types of proteins which do not specifically bind the materials to be employed in the assay. Thus9 for example, the residual binding capacity of the substrate may be blocked so as to prevent non-specific binding by the use of bovine serum albumin.
The techniques for preventing non-specific binding are generally known in the art, and such techniques are also generally applicable to preventing non-specific binding in the assay of the present invention.
In accordance with the present invention, the first portion of the solid support rnay be provided with the tracer, during the assay procedure, or the solid support may be produced with the tracer on the first portion thereof. In the latter case, the tracer is supported on the support in a manner such that upon wetting of the first portion, the tracer flows by capillarity to the third portion of the solid suport. Thus, for example, the tracer may be absorbed on the soli-d support, in the first portion thereof, whereby upon wetting of the first portion during the assay, the tracer flows by capillarity to the third portion of the solid support which includes the binder, as hereinabove described.
The invention will be further described with respect to embodiments thereof illustrated in the accompanying drawings wherein: ~
Referring to Figure 1, there is shown a test card 10, r~
which is generelly comprised of an upper card member 11 and a lower card member 12. The upper card member 11 is r~
provided with A tracer loading port 13, sample loading port __ 14 and a test view window or port 15.. A test sheet 16~
preferably nitrocellulose9 is placed between the upper and lower csrd members 11 and 12, respectively, with Q portion Qf the nitrocellulose being vi~ible through test port 15.
At least a portion of the sheet 16 which is viewable through window lS includes a binder specific for the analyte to be assayed and defines ~ test area. A first strip of absorbent materiAl 17 is placed between the upper and lower card members 11 and 12 and extends between tracer loading port 13 and view window 15 with the aborbent material 17 being in contact with test sheet 16. A second strip of absorbent material 18 is placed between the upper and lower card members 11 and 12 and extends between sample loading port 14 and view window 15, with the absorbent material 18 being in contact with the test sheet 16. As shown, the strips 17 and 18 are separ~te and distinct from each other and provide separate capillary flow paths from each of ports 13 and }4 to view window 15. Strips 17 and 18 may be formed, for example, from glass fiber.
As particularly shown, the sample loading port 14 is closer to the viewing window 15 than the tracer loading port 13, whereby the capillary flow path between ports 14 and 15 is shorter than the capillary flow path between ports 13 and 15. In addition, the strip 17 may be treated with a material to reduce the capillary rate of flow.
A p-iece of material 21 having a high liquid absorption capacity, such as blotting paper, is positioned between upper and lower card member l~ and 12 in contact with test sheet 18 to receive and store test materialO
In an assRy, a sample to be assayed is applied through test port 14 and tr~cer is applied through test port 13.
The sample flows to the test sheet 16 through strip 18 and the tracer- flows to test sheet 16 through strip 17. As hereinabove indica~ed, the flow paths and/or strips ~re constructed in a manner such that the sample contacts the binder on the test sheet 16, prior to contact of the tracer with either the binder or sampleO The tracer may then be determined through test window 15.
The presence and/or amount of analyte present in the sample may be determined by the presence and/or amount of tracer, as determined through window 15 of the card 10.
ln accordance with a preferred embodiment, as hereinabove described, by using an appropriate material as sheet 16 (for example, nitrocellulose) and a visible particulate label (such as a liposome including Q SUi table dye), it is possible to determine tracer through window 15 without destruction of the liposome.
Although the embodiment has been described with respect to the use of a tracer which includes a visible particulate label, it is to be understood that other detectable labels may be employed within the spirit and scope of the invention; e.g., an enzyme label; a chromogen label (fluorescent and/or absorbing dye), etc. ln such cases, it may be necessary to add an additional substance in order to detect the label in view window 15; e.g. t in the case of an enzyme label, a substrate to produce detectable eolor in the view window.
It is also possible to provide a view window over the material 21 in place o~ or in con~unction with the view window 15. In this m~nner~ tracer wh~ch hss not been bound in test sheet portion 16 may be de~ermined. The presence and/or amount of tracer In portion 21 may be employed to determine analyte ~lone ~nd/or in con~unction with the presence and/or ~mount or ~nalyte in portion 16.
The invention will be further described witb respect to the following ex~mple; however, the scope of the invention is not to be limited thereby:
EXA~PLE
___ A reaction c~rd 10 was constructed using two plastic cards 11 and 12. The cards were made of polypropylene with a thickness of approximately 0.03 inches. The top card has three holes which include a view window 15, liposome trscer loading port 13, ~nd a s~mple lo~ding port 14. The view Ir window has 8 diameter of approximately 12.0 mm while the loading ports ~re 6maller (4.0 mm).
jThe first step in construction W8~ to place double . *
.;.stick adhesive (3,M Type 960) over the entire card.
Nitrocellulose ~5.0 ~ S~S) with the capture ~ntibody was ¦~ttached to the card as test sheet 16. Sheet 1~ was spotted with 3 Ol of affinity purified r~bbit anti-Group A
antigen and then blocked with 3% bovine serum :
albumin. The antibody portion is below window 15.
Blotting paper 21 (Gelman 51334) was placed on the card such that the paper was in cont~ct with the nitrocellulose.
The window and lo~ding ports were punched ou~ of a second card. Adhesive was placed over the holes and excess Adhesive was removed from the holss. This process led to a card that had adhesive completely surroun~ing the ports.
* Trademark~ -16 1 3t 7~63 Next, str ips of glass f iber (Whatman ~F/A3 17 ~nd 18 were pl~ced sn the card such that they m~de a connection from the lo~ding ports to the ~iew window. Strip 18 is treated with a 3% B5A solution.
Detector lipsomes packed with sulfo-rhodamine dye were prepared by the method outljned in O'C~nnell et al. ~CIin.
. Chem. 31:1424 E198s~). They were covalently coupled to affinity purified rabbit anti-Group A ~ 2~ 2 antigen.
Group A S~reptococcus organisms were harvested from culture plates, washed with saline (0.9% NaC1~, ~nd adjusted to 1 x 109 orgsnisms/ml. An aliquot (0.1 mlj containing 1 x 108 organisms w~s subjected to the miero nitrous acid extractlon method for exposing the Group A
carbohydrate antigen. This method consists of mixing 0.3 ml of 0.1 M HCl with 40 ul of 4~ NaNO2., adding this to the Stre~tococcus org~nisms and, ~fter 3 minutes, neturalizing : with 40 ul of 1~ rris base. To facilitate the extraction, the HC1 and the subsequent diluting fluid contain 0.1%
i Tween-20 non-ionic detergent.
I A reservolr was attached to the device to assure that all the sample (0,3 ml) could be added at one time.
Immediately after addition of the sample through port 14 the liposome tracer was added to the tracer port i3. No other m~nipulations were re~uired. Within five minutes a specific signal ~t the c~pture antibody spot. (Window 153 could be seen at Q sensitiYity level equivalent to 1 X 106 CF~/ml.
~ he present invention is advantageous in that it is possible to provid~ 8 sandwi~h ass~y wi~hout separate 7~
* Trademark ~17-13~7863 incubation und wash steps, and which has the requisite sensitivityO
These and other advanteges should be spparent to those skilled in the art.
Numerous modifications and veriations of the present invention are possible in light of the above teachings and, therefore9 within the seope of the appended claims, the invention may be practised otherwise than as particularly described.
Claims (10)
1. An assay for determining analyte for a sample comprising:
providing a solid support with a sample to be assayed, said solid support including a first portion, a second portion and a third portion, said third portion being in capillary flow communication with both the first and second portions, said third portion including a binder for the analyte, said first portion of the support receiving said sample, said second portion receiving a tracer; moving tracer and sample by capillary flow from the second and first portions to the third portion to provide contact between tracer, binder and sample to thereby provide a complex in the third portion of any analyte in the sample, binder and tracer; and determining at least one of tracer in said third portion of the support or a tracer which has passed through the third portion of the support to determine analyte.
providing a solid support with a sample to be assayed, said solid support including a first portion, a second portion and a third portion, said third portion being in capillary flow communication with both the first and second portions, said third portion including a binder for the analyte, said first portion of the support receiving said sample, said second portion receiving a tracer; moving tracer and sample by capillary flow from the second and first portions to the third portion to provide contact between tracer, binder and sample to thereby provide a complex in the third portion of any analyte in the sample, binder and tracer; and determining at least one of tracer in said third portion of the support or a tracer which has passed through the third portion of the support to determine analyte.
2. The assay of Claim 1 wherein said tracer and sample are moved by capillary flow to provide contact between sample and binder prior to substantial contact of the tracer with either the sample or binder.
3. The assay of Claim 2 wherein the tracer is comprised of a ligand and a particulate label.
4. The assay of Claim 3 wherein the partic-ulate label is a liposome including a colored sub-stance.
5. The assay of Claim 4 wherein the tracer and sample move by capillary flow to the third portion through separate and distinct flow paths.
6. An article of manufacture for determin-ing analyte, comprising:
a solid support including first, second and third absorbent material portions, said first portion including a sample receiving portion, said second portion including a tracer receiving portion, said third portion including a binder for the analyte to be assayed, said third portion being in capillary flow communication with both the sample and tracer receiving portions to provide for capillary flow of sample and tracer to the third portion to provide contact between tracer, sample and binder.
a solid support including first, second and third absorbent material portions, said first portion including a sample receiving portion, said second portion including a tracer receiving portion, said third portion including a binder for the analyte to be assayed, said third portion being in capillary flow communication with both the sample and tracer receiving portions to provide for capillary flow of sample and tracer to the third portion to provide contact between tracer, sample and binder.
7. The article of Claim 6 wherein a first absorbent material portion defines a first flow path for capillary flow between the sample receiving portion and the third portion including the binder, and a second absorbent material portion defines a second flow path for capillary flow between the tracer receiving portion and the third portion including the binder.
8. The article of Claim 7 wherein the flow path between the sample receiving portion and the third portion is shorter than the flow path between the tracer receiving portion and the third portion.
9. The article of Claim 7 wherein the second absorbent material portion is treated with an agent to inhibit wetting thereof to reduce the rate of flow between the tracer receiving portion and third portion.
10. The article of Claim 7 wherein the support includes an absorbent material in contact with the third portion to receive and store any sample and tracer which flows through the third portion.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/049,328 US4855240A (en) | 1987-05-13 | 1987-05-13 | Solid phase assay employing capillary flow |
| US049,328 | 1987-05-13 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1317863C true CA1317863C (en) | 1993-05-18 |
Family
ID=21959230
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000562173A Expired - Fee Related CA1317863C (en) | 1987-05-13 | 1988-03-23 | Solid phase assay employing capillary flow |
Country Status (12)
| Country | Link |
|---|---|
| US (1) | US4855240A (en) |
| EP (1) | EP0291176B1 (en) |
| JP (1) | JPH0718876B2 (en) |
| KR (1) | KR900005482B1 (en) |
| AT (1) | ATE69311T1 (en) |
| AU (1) | AU609795B2 (en) |
| CA (1) | CA1317863C (en) |
| DE (1) | DE3866011D1 (en) |
| DK (1) | DK265688A (en) |
| ES (1) | ES2027760T3 (en) |
| FI (1) | FI88965C (en) |
| GR (1) | GR3003073T3 (en) |
Families Citing this family (229)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5622871A (en) | 1987-04-27 | 1997-04-22 | Unilever Patent Holdings B.V. | Capillary immunoassay and device therefor comprising mobilizable particulate labelled reagents |
| US5763262A (en) * | 1986-09-18 | 1998-06-09 | Quidel Corporation | Immunodiagnostic device |
| US20010023075A1 (en) * | 1992-04-03 | 2001-09-20 | Siu-Yin Wong | A immunodiagnositc device having a dessicant incorporated therein |
| US4960691A (en) * | 1986-09-29 | 1990-10-02 | Abbott Laboratories | Chromatographic test strip for determining ligands or receptors |
| CA1303983C (en) * | 1987-03-27 | 1992-06-23 | Robert W. Rosenstein | Solid phase assay |
| USRE38430E1 (en) * | 1987-03-27 | 2004-02-17 | Becton, Dickinson And Company | Solid phase chromatographic immunoassay |
| DE560410T1 (en) | 1987-04-27 | 2001-12-20 | Unilever Nv | Test device for carrying out specific binding tests. |
| US5238847A (en) * | 1987-05-20 | 1993-08-24 | Boehringer Mannheim Gmbh | Test kit and process for the determination of an analyte in a pasty sample |
| US5120643A (en) * | 1987-07-13 | 1992-06-09 | Abbott Laboratories | Process for immunochromatography with colloidal particles |
| EP0306772B1 (en) * | 1987-09-11 | 1993-03-10 | Abbott Laboratories | Lateral flow chromatographic binding assay device |
| JPH01214760A (en) * | 1988-02-23 | 1989-08-29 | Teikoku Hormone Mfg Co Ltd | Simple immunological measuring method |
| US4963478A (en) * | 1988-07-05 | 1990-10-16 | Immucor, Inc. | Article for preforming immunological assays utilizing organic dyes and method for producing and utilizing same |
| US6352862B1 (en) | 1989-02-17 | 2002-03-05 | Unilever Patent Holdings B.V. | Analytical test device for imuno assays and methods of using same |
| US5135872A (en) * | 1989-04-28 | 1992-08-04 | Sangstat Medical Corporation | Matrix controlled method of delayed fluid delivery for assays |
| CA2025476A1 (en) * | 1989-09-27 | 1991-03-28 | Shan F. Ching | Hydrophilic laminated porous membranes and methods of preparing same |
| AU642444B2 (en) * | 1989-11-30 | 1993-10-21 | Mochida Pharmaceutical Co., Ltd. | Reaction vessel |
| US5096837A (en) * | 1990-02-08 | 1992-03-17 | Pacific Biotech, Inc. | Immunochromatographic assay and method of using same |
| US5223220A (en) * | 1990-03-27 | 1993-06-29 | Pacific Biotech, Inc. | Solid phase immunoassay device and method of making same |
| CA2076876A1 (en) * | 1990-03-27 | 1991-09-28 | Eugene Fan | Solid phase immunoassay and method of making same |
| US5106582A (en) * | 1990-12-18 | 1992-04-21 | Smithkline Diagnostics, Inc. | Specimen test slide and method of testing for fecal occult blood |
| DE69229334T2 (en) * | 1991-01-11 | 1999-12-16 | Quidel Corp | ONE-STAGE CROSS-FLOW ANALYZING METHOD AND A NON-SUCTIONABLE CARRIER USED IN IT |
| US5877028A (en) | 1991-05-29 | 1999-03-02 | Smithkline Diagnostics, Inc. | Immunochromatographic assay device |
| US5869345A (en) * | 1991-05-29 | 1999-02-09 | Smithkline Diagnostics, Inc. | Opposable-element assay device employing conductive barrier |
| US5607863A (en) * | 1991-05-29 | 1997-03-04 | Smithkline Diagnostics, Inc. | Barrier-controlled assay device |
| US6168956B1 (en) | 1991-05-29 | 2001-01-02 | Beckman Coulter, Inc. | Multiple component chromatographic assay device |
| US5468648A (en) * | 1991-05-29 | 1995-11-21 | Smithkline Diagnostics, Inc. | Interrupted-flow assay device |
| US5998220A (en) | 1991-05-29 | 1999-12-07 | Beckman Coulter, Inc. | Opposable-element assay devices, kits, and methods employing them |
| US5686315A (en) * | 1991-06-14 | 1997-11-11 | Quidel Corporation | Assay device for one step detection of analyte |
| GB9123922D0 (en) * | 1991-11-11 | 1992-01-02 | Bunce Roger A | Liquid transfer devices |
| US5278079A (en) * | 1992-09-02 | 1994-01-11 | Enzymatics, Inc. | Sealing device and method for inhibition of flow in capillary measuring devices |
| US5354692A (en) * | 1992-09-08 | 1994-10-11 | Pacific Biotech, Inc. | Analyte detection device including a hydrophobic barrier for improved fluid flow |
| AU670108B2 (en) | 1992-09-11 | 1996-07-04 | Becton Dickinson & Company | Improved antibodies to plasmodium falciparum |
| US5503985A (en) * | 1993-02-18 | 1996-04-02 | Cathey; Cheryl A. | Disposable device for diagnostic assays |
| US5798215A (en) * | 1993-02-18 | 1998-08-25 | Biocircuits Corporation | Device for use in analyte detection assays |
| US5837546A (en) * | 1993-08-24 | 1998-11-17 | Metrika, Inc. | Electronic assay device and method |
| US5658747A (en) * | 1994-05-10 | 1997-08-19 | Biocontrol System, Inc. | Compositions and methods for control of reactivity between diagnostic reagents and microorganisms |
| JPH08172056A (en) * | 1994-12-20 | 1996-07-02 | Mitsubishi Electric Corp | Growing method of compound semiconductor layer |
| WO1996036878A1 (en) * | 1995-05-19 | 1996-11-21 | Universal Healthwatch, Inc. | Rapid self-contained assay format |
| US7635597B2 (en) | 1995-08-09 | 2009-12-22 | Bayer Healthcare Llc | Dry reagent particle assay and device having multiple test zones and method therefor |
| US5981294A (en) * | 1995-11-29 | 1999-11-09 | Metrika, Inc. | Device for blood separation in a diagnostic device |
| US5753517A (en) * | 1996-03-29 | 1998-05-19 | University Of British Columbia | Quantitative immunochromatographic assays |
| US5968839A (en) * | 1996-05-13 | 1999-10-19 | Metrika, Inc. | Method and device producing a predetermined distribution of detectable change in assays |
| US5945345A (en) * | 1996-08-27 | 1999-08-31 | Metrika, Inc. | Device for preventing assay interference using silver or lead to remove the interferant |
| US6194220B1 (en) * | 1996-09-25 | 2001-02-27 | Becton, Dickinson And Company | Non-instrumented assay with quantitative and qualitative results |
| US6165798A (en) * | 1996-10-10 | 2000-12-26 | University Of British Columbia | Optical quantification of analytes in membranes |
| US5879951A (en) | 1997-01-29 | 1999-03-09 | Smithkline Diagnostics, Inc. | Opposable-element assay device employing unidirectional flow |
| US20050101032A1 (en) * | 1997-02-10 | 2005-05-12 | Metrika, Inc. | Assay device, composition, and method of optimizing assay sensitivity |
| US5939252A (en) | 1997-05-09 | 1999-08-17 | Lennon; Donald J. | Detachable-element assay device |
| DE69840657D1 (en) | 1997-07-16 | 2009-04-23 | Charm Sciences Inc | Method for detecting a residual analyte in a sample |
| US5985675A (en) | 1997-12-31 | 1999-11-16 | Charm Sciences, Inc. | Test device for detection of an analyte |
| UA78180C2 (en) | 1997-10-03 | 2007-03-15 | Меріаль | Porcine circovirus, vaccines and diagnostic reagents |
| CA2312102C (en) | 1997-12-24 | 2007-09-04 | Cepheid | Integrated fluid manipulation cartridge |
| US6267722B1 (en) | 1998-02-03 | 2001-07-31 | Adeza Biomedical Corporation | Point of care diagnostic systems |
| US6394952B1 (en) | 1998-02-03 | 2002-05-28 | Adeza Biomedical Corporation | Point of care diagnostic systems |
| US6303081B1 (en) * | 1998-03-30 | 2001-10-16 | Orasure Technologies, Inc. | Device for collection and assay of oral fluids |
| US8062908B2 (en) * | 1999-03-29 | 2011-11-22 | Orasure Technologies, Inc. | Device for collection and assay of oral fluids |
| ES2501241T3 (en) * | 1998-03-30 | 2014-10-01 | Orasure Technologies, Inc. | Collection device for oral fluid analysis |
| USD432244S (en) * | 1998-04-20 | 2000-10-17 | Adeza Biomedical Corporation | Device for encasing an assay test strip |
| USD434153S (en) * | 1998-04-20 | 2000-11-21 | Adeza Biomedical Corporation | Point of care analyte detector system |
| SE9801563D0 (en) | 1998-04-30 | 1998-04-30 | Pharmacia & Upjohn Diag Ab | Method of separation and kit to be used in the process |
| US7640083B2 (en) | 2002-11-22 | 2009-12-29 | Monroe David A | Record and playback system for aircraft |
| JP3395673B2 (en) | 1998-11-18 | 2003-04-14 | 株式会社豊田中央研究所 | Specific binding pair measurement method using micro oxygen electrode |
| GB9827411D0 (en) | 1998-12-11 | 1999-02-03 | Axis Biochemicals Asa | Dipstick assay |
| US6431476B1 (en) | 1999-12-21 | 2002-08-13 | Cepheid | Apparatus and method for rapid ultrasonic disruption of cells or viruses |
| US7914994B2 (en) | 1998-12-24 | 2011-03-29 | Cepheid | Method for separating an analyte from a sample |
| JP4022069B2 (en) | 1999-05-28 | 2007-12-12 | シーフィード | Cell disruption apparatus and method |
| US8815521B2 (en) | 2000-05-30 | 2014-08-26 | Cepheid | Apparatus and method for cell disruption |
| US9073053B2 (en) | 1999-05-28 | 2015-07-07 | Cepheid | Apparatus and method for cell disruption |
| US20040200909A1 (en) * | 1999-05-28 | 2004-10-14 | Cepheid | Apparatus and method for cell disruption |
| CA2375532A1 (en) * | 1999-06-23 | 2000-12-28 | Cornell Research Foundation, Inc. | Dehydration/rehydration of marked liposomes on a test device |
| US6664104B2 (en) | 1999-06-25 | 2003-12-16 | Cepheid | Device incorporating a microfluidic chip for separating analyte from a sample |
| AU780935B2 (en) | 1999-09-13 | 2005-04-28 | Equitech Laboratories, Inc. | Materials and methods for the determination of an analyte |
| US6576460B1 (en) | 1999-10-28 | 2003-06-10 | Cornell Research Foundation, Inc. | Filtration-detection device and method of use |
| DE10003734A1 (en) * | 2000-01-28 | 2001-08-02 | Bosch Gmbh Robert | Detection method and device |
| US6998273B1 (en) | 2000-02-09 | 2006-02-14 | A-Fem Medical Corporation | Collection device for lateral flow chromatography |
| US6365417B1 (en) | 2000-02-09 | 2002-04-02 | A-Fem Medical Corporation | Collection device for lateral flow chromatography |
| AU783559B2 (en) * | 2000-03-09 | 2005-11-10 | Colorado State University Research Foundation | Use of recombinant antigens to determine the immune status of an animal |
| US6699722B2 (en) | 2000-04-14 | 2004-03-02 | A-Fem Medical Corporation | Positive detection lateral-flow apparatus and method for small and large analytes |
| US6706474B1 (en) * | 2000-06-27 | 2004-03-16 | Board Of Trustees Of The University Of Illinois | Nucleic acid enzyme biosensors for ions |
| GB0016813D0 (en) * | 2000-07-07 | 2000-08-30 | Lee Helen | Improved dipstick assays (4) |
| NO314206B1 (en) * | 2001-04-30 | 2003-02-10 | Erling Sundrehagen | Quantitative chemical analysis method, device / device, and application of said method and analysis set |
| US7270959B2 (en) | 2001-07-25 | 2007-09-18 | Oakville Hong Kong Company Limited | Specimen collection container |
| US7300633B2 (en) | 2001-07-25 | 2007-11-27 | Oakville Hong Kong Company Limited | Specimen collection container |
| US6969489B2 (en) * | 2001-08-24 | 2005-11-29 | Cytoplex Biosciences | Micro array for high throughout screening |
| US7393696B2 (en) * | 2001-09-28 | 2008-07-01 | Aspenbio Pharma, Inc. | Bovine pregnancy test |
| US8481334B1 (en) | 2001-11-06 | 2013-07-09 | Charm Sciences, Inc. | Method of attaching a ligand to a solid support |
| US20030119203A1 (en) | 2001-12-24 | 2003-06-26 | Kimberly-Clark Worldwide, Inc. | Lateral flow assay devices and methods for conducting assays |
| US8367013B2 (en) | 2001-12-24 | 2013-02-05 | Kimberly-Clark Worldwide, Inc. | Reading device, method, and system for conducting lateral flow assays |
| US6837171B1 (en) | 2002-04-29 | 2005-01-04 | Palmer/Snyder Furniture Company | Lightweight table with unitized table top |
| US7122314B2 (en) * | 2002-01-30 | 2006-10-17 | Id Biomedical Corporation | Methods for detecting vancomycin-resistant microorganisms and compositions therefor |
| US6890719B2 (en) * | 2002-05-10 | 2005-05-10 | The Board Of Trustess Of The University Of Illinois | Fluorescence based biosensor |
| US7534560B2 (en) | 2002-05-10 | 2009-05-19 | The Board Of Trustees Of The University Of Illinois | Simple catalytic DNA biosensors for ions based on color changes |
| EP1939627B1 (en) | 2002-05-31 | 2010-08-18 | Cornell Research Foundation, Inc. | Methods to detect analytes in samples |
| US7314763B2 (en) | 2002-08-27 | 2008-01-01 | Kimberly-Clark Worldwide, Inc. | Fluidics-based assay devices |
| US7285424B2 (en) | 2002-08-27 | 2007-10-23 | Kimberly-Clark Worldwide, Inc. | Membrane-based assay devices |
| US7432105B2 (en) | 2002-08-27 | 2008-10-07 | Kimberly-Clark Worldwide, Inc. | Self-calibration system for a magnetic binding assay |
| US20040092036A1 (en) * | 2002-09-11 | 2004-05-13 | Lattec I/S | Device for analysing analyte compounds and use hereof |
| KR100522394B1 (en) * | 2002-11-07 | 2005-10-18 | 황춘홍 | Card useful for storing specimen |
| US7247500B2 (en) | 2002-12-19 | 2007-07-24 | Kimberly-Clark Worldwide, Inc. | Reduction of the hook effect in membrane-based assay devices |
| US7560272B2 (en) | 2003-01-04 | 2009-07-14 | Inverness Medical Switzerland Gmbh | Specimen collection and assay container |
| US7612185B2 (en) * | 2003-03-07 | 2009-11-03 | The Board Of Trustees Of The University Of Illinois | Nucleic acid biosensors |
| US20040178714A1 (en) * | 2003-03-11 | 2004-09-16 | Pan Wun Fang | Decorative bulb of a series connected light string |
| US7851209B2 (en) | 2003-04-03 | 2010-12-14 | Kimberly-Clark Worldwide, Inc. | Reduction of the hook effect in assay devices |
| US20040197819A1 (en) | 2003-04-03 | 2004-10-07 | Kimberly-Clark Worldwide, Inc. | Assay devices that utilize hollow particles |
| US7393697B2 (en) | 2003-06-06 | 2008-07-01 | Advantage Diagnostics Corporation | Diagnostic test for analytes in a sample |
| US7517495B2 (en) | 2003-08-25 | 2009-04-14 | Inverness Medical Switzerland Gmbh | Biological specimen collection and analysis system |
| US7722817B2 (en) * | 2003-08-28 | 2010-05-25 | Epocal Inc. | Lateral flow diagnostic devices with instrument controlled fluidics |
| US7943395B2 (en) | 2003-11-21 | 2011-05-17 | Kimberly-Clark Worldwide, Inc. | Extension of the dynamic detection range of assay devices |
| US7713748B2 (en) | 2003-11-21 | 2010-05-11 | Kimberly-Clark Worldwide, Inc. | Method of reducing the sensitivity of assay devices |
| US20050112703A1 (en) | 2003-11-21 | 2005-05-26 | Kimberly-Clark Worldwide, Inc. | Membrane-based lateral flow assay devices that utilize phosphorescent detection |
| US7410808B1 (en) | 2003-12-08 | 2008-08-12 | Charm Sciences, Inc. | Method and assay for detection of residues |
| US7943089B2 (en) | 2003-12-19 | 2011-05-17 | Kimberly-Clark Worldwide, Inc. | Laminated assay devices |
| US7485419B2 (en) * | 2004-01-13 | 2009-02-03 | The Board Of Trustees Of The University Of Illinois | Biosensors based on directed assembly of particles |
| US7150995B2 (en) | 2004-01-16 | 2006-12-19 | Metrika, Inc. | Methods and systems for point of care bodily fluid analysis |
| US7319032B2 (en) * | 2004-04-22 | 2008-01-15 | Medtox | Non-sugar sweeteners for use in test devices |
| US7521226B2 (en) | 2004-06-30 | 2009-04-21 | Kimberly-Clark Worldwide, Inc. | One-step enzymatic and amine detection technique |
| US20060094026A1 (en) * | 2004-11-03 | 2006-05-04 | Yi Lu | Nucleic acid enzyme light-up sensor utilizing invasive DNA |
| US20070207496A1 (en) * | 2004-11-19 | 2007-09-06 | Larsen Oeistein | Diagnostic control system |
| US7465587B2 (en) * | 2004-12-03 | 2008-12-16 | Genzyme Corporation | Diagnostic assay device |
| US7682817B2 (en) * | 2004-12-23 | 2010-03-23 | Kimberly-Clark Worldwide, Inc. | Microfluidic assay devices |
| US20060166222A1 (en) * | 2005-01-21 | 2006-07-27 | Yi Lu | Nucleic acid enzyme ligation sensor |
| WO2006080021A2 (en) | 2005-01-31 | 2006-08-03 | Realbio Technologies Ltd. | Multistep reaction lateral flow capillary device |
| US7189522B2 (en) | 2005-03-11 | 2007-03-13 | Chembio Diagnostic Systems, Inc. | Dual path immunoassay device |
| WO2006098804A2 (en) | 2005-03-11 | 2006-09-21 | Chembio Diagnostic Systems, Inc. | Dual path immunoassay device |
| US7858384B2 (en) * | 2005-04-29 | 2010-12-28 | Kimberly-Clark Worldwide, Inc. | Flow control technique for assay devices |
| US7803319B2 (en) * | 2005-04-29 | 2010-09-28 | Kimberly-Clark Worldwide, Inc. | Metering technique for lateral flow assay devices |
| US20070042427A1 (en) * | 2005-05-03 | 2007-02-22 | Micronics, Inc. | Microfluidic laminar flow detection strip |
| AU2006321289B2 (en) | 2005-05-23 | 2011-12-08 | Phadia Ab | Two step lateral flow assay methods and devices |
| US20070015166A1 (en) * | 2005-07-14 | 2007-01-18 | Nilsen Thor W | Lateral flow methods and devices for detection of nucleic acid binding proteins |
| US7892734B2 (en) * | 2005-08-11 | 2011-02-22 | The Board Of Trustees Of The University Of Illinois | Aptamer based colorimetric sensor systems |
| KR100726026B1 (en) * | 2005-09-08 | 2007-06-08 | 건국대학교 산학협력단 | The moisture sample measurement device and its measurement method |
| US7344893B2 (en) * | 2005-10-13 | 2008-03-18 | Auric Enterprises, Llc | Immuno-gold lateral flow assay |
| US20070224701A1 (en) * | 2006-02-16 | 2007-09-27 | Becton, Dickinson And Company | Combination vertical and lateral flow immunoassay device |
| ES2393758T3 (en) | 2006-03-15 | 2012-12-27 | Micronics, Inc. | Integrated nucleic acid assays |
| US7799554B2 (en) * | 2006-03-16 | 2010-09-21 | The Board Of Trustees Of The University Of Illinois | Lateral flow devices |
| US7569396B1 (en) | 2006-09-08 | 2009-08-04 | Purplecow Llc | Caffeine detection using internally referenced competitive assays |
| US20080138842A1 (en) * | 2006-12-11 | 2008-06-12 | Hans Boehringer | Indirect lateral flow sandwich assay |
| US8012761B2 (en) * | 2006-12-14 | 2011-09-06 | Kimberly-Clark Worldwide, Inc. | Detection of formaldehyde in urine samples |
| US7846383B2 (en) * | 2006-12-15 | 2010-12-07 | Kimberly-Clark Worldwide, Inc. | Lateral flow assay device and absorbent article containing same |
| WO2008089248A2 (en) * | 2007-01-19 | 2008-07-24 | The Board Of Trustees Of The University Of Illinois | Amphiphilic substances and triggered liberation from lipid vesicles |
| JP2008249339A (en) * | 2007-03-29 | 2008-10-16 | Gc Corp | Immunochromatography test tool |
| US8058415B2 (en) | 2007-04-24 | 2011-11-15 | The Board Of Trustees Of The University Of Illinois | Aptamer- and nucleic acid enzyme-based systems for simultaneous detection of multiple analytes |
| US20080317633A1 (en) * | 2007-04-30 | 2008-12-25 | Stc.Unm | Multiplex lateral flow devices and methods |
| US8409800B2 (en) * | 2007-07-16 | 2013-04-02 | The Board Of Trustees Of The University Of Illinois | Nucleic acid based fluorescent sensor for copper detection |
| US8568690B2 (en) * | 2007-07-31 | 2013-10-29 | The Board Of Trustees Of The University Of Illinois | MRI contrast agents and high-throughput screening by MRI |
| WO2009045632A2 (en) | 2007-08-10 | 2009-04-09 | The Board Of Trustees Of The University Of Illinois | Nucleic acid based fluorescent sensor for mercury detection |
| JP5248613B2 (en) * | 2007-09-17 | 2013-07-31 | レッド・アイボリー・エルエルシー | Self-actuating signal generation detection apparatus and method |
| JP4865664B2 (en) * | 2007-09-28 | 2012-02-01 | 富士フイルム株式会社 | Method of mixing two or more liquids in a porous carrier |
| US8673644B2 (en) | 2008-05-13 | 2014-03-18 | Battelle Memorial Institute | Serum markers for type II diabetes mellitus |
| US20100105039A1 (en) * | 2008-06-03 | 2010-04-29 | Yi Lu | Label-free colorimetric detection |
| EP2326419B1 (en) | 2008-06-29 | 2021-04-07 | Realbio Technologies Ltd. | Liquid transfer device particularly useful as a capturing device in a biological assay process |
| US8476008B2 (en) * | 2008-07-23 | 2013-07-02 | Diabetomics, Llc | Methods for detecting pre-diabetes and diabetes |
| US20100022916A1 (en) | 2008-07-24 | 2010-01-28 | Javanbakhsh Esfandiari | Method and Apparatus for Collecting and Preparing Biological Samples for Testing |
| JP5066498B2 (en) * | 2008-09-19 | 2012-11-07 | 富士フイルム株式会社 | Assay method |
| US8062893B2 (en) | 2008-10-10 | 2011-11-22 | The Board Of Trustees Of The University Of Illinois | Fluorescent sensor for mercury |
| US9234889B1 (en) | 2008-12-18 | 2016-01-12 | Charm Sciences, Inc. | Method and test strip for detecting residues |
| US10203310B2 (en) | 2009-01-26 | 2019-02-12 | Detectachem Llc | Chemical detection of substances by utilizing a sample medium impregnated with solid test chemicals |
| CA2750818A1 (en) | 2009-01-27 | 2010-08-05 | Proteogenix, Inc. | Biomarkers for detection of neonatal sepsis in biological fluid |
| WO2010132447A2 (en) | 2009-05-11 | 2010-11-18 | Diabetomics, Llc | Methods for detecting pre-diabetes and diabetes using differential protein glycosylation |
| EP2496941B1 (en) | 2009-11-04 | 2016-07-13 | Thomas M. Buchanan | Methods and devices to enhance sensitivity and evaluate sample adequacy and reagent reactivity in rapid lateral flow immunoassays |
| EP2504706B1 (en) | 2009-11-25 | 2018-05-23 | Hologic Inc. | Detection of intraamniotic infection |
| KR101851117B1 (en) | 2010-01-29 | 2018-04-23 | 마이크로닉스 인코포레이티드. | Sample-to-answer microfluidic cartridge |
| EP4012714A1 (en) | 2010-03-23 | 2022-06-15 | Iogenetics, LLC. | Bioinformatic processes for determination of peptide binding |
| MX2012011667A (en) | 2010-04-09 | 2013-03-05 | Critical Care Diagnostics Inc | Soluble human st-2 antibodies and assays. |
| EP2566949B1 (en) | 2010-05-06 | 2023-02-15 | Charm Sciences, Inc. | Reader-incubator apparatus |
| US8945943B2 (en) | 2010-05-26 | 2015-02-03 | The Board Of Trustees Of The University Of Illinois | Personal glucose meters for detection and quantification of a broad range of analytes |
| US8815156B2 (en) | 2010-07-19 | 2014-08-26 | Andalyze, Inc. | Sensor housing and reagent chemistry |
| US8956859B1 (en) | 2010-08-13 | 2015-02-17 | Aviex Technologies Llc | Compositions and methods for determining successful immunization by one or more vaccines |
| FR2967497B1 (en) * | 2010-11-17 | 2014-12-12 | Biomerieux Sa | DEVICE AND METHOD FOR IMMUNOASSAY |
| US20120302456A1 (en) * | 2010-11-23 | 2012-11-29 | President And Fellows Of Harvard College | Vertical flow-through devices for multiplexed elisa driven by wicking |
| US8603835B2 (en) | 2011-02-10 | 2013-12-10 | Chembio Diagnostic Systems, Inc. | Reduced step dual path immunoassay device and method |
| JP2014508306A (en) * | 2011-03-15 | 2014-04-03 | カルクロ テクニカル プラスチックス リミテッド | Sample measurement |
| EP2771349B1 (en) | 2011-09-16 | 2020-02-26 | Iogenetics, LLC. | Bioinformatic processes for determination of peptide binding |
| US9554736B2 (en) | 2011-11-29 | 2017-01-31 | Teleflex Medical Incorporated | Device with integrated allergy testing |
| JP6000369B2 (en) | 2011-11-29 | 2016-09-28 | テレフレックス メディカル インコーポレイテッドＴｅｌｅｆｌｅｘ Ｍｅｄｉｃａｌ Ｉｎｃｏｒｐｏｒａｔｅｄ | Integrated allergy testing instrument |
| CN105833925B (en) | 2011-12-22 | 2018-11-13 | 瑞尔比奥技术有限公司 | sequential lateral flow capillary device for analyte determination |
| EP2807271B1 (en) | 2012-01-24 | 2018-08-22 | CD Diagnostics, Inc. | System for detecting infection in synovial fluid |
| EP2812704A4 (en) | 2012-02-07 | 2016-03-23 | Intuitive Biosciences Inc | Mycobacterium tuberculosis specific peptides for detection of infection or immunization in non-human primates |
| US20130280696A1 (en) | 2012-04-23 | 2013-10-24 | Elliott Millenson | Devices and methods for detecting analyte in bodily fluid |
| DE202012012084U1 (en) | 2012-07-09 | 2013-04-15 | Schebo Biotech Ag | Test kit (combi rapid test) for the synchronous detection of biomarkers in stool for the detection of pathological changes in the gastrointestinal tract, especially in the intestine |
| DE102012013888A1 (en) | 2012-07-09 | 2014-05-22 | Schebo Biotech Ag | Test kit (combi rapid test) for the synchronous detection of biomarkers in stool for the detection of pathological changes in the gastrointestinal tract, especially in the intestine |
| US9360479B2 (en) | 2012-11-15 | 2016-06-07 | Daniel Wang | Rapid lateral flow assay method for low quantity liquid or dry samples |
| WO2014081460A1 (en) * | 2012-11-20 | 2014-05-30 | Kisner Mark | Chemical sequencing and control to expand and enhance detection capabilities utilizing a colorimetric test |
| WO2014087255A2 (en) | 2012-11-21 | 2014-06-12 | Oslo Universitetssykehus Hf | Systems and methods for monitoring biological fluids |
| JP6498125B2 (en) | 2012-12-21 | 2019-04-10 | マイクロニクス， インコーポレイテッド | Fluid circuit and associated manufacturing method |
| JP2016509206A (en) | 2012-12-21 | 2016-03-24 | マイクロニクス， インコーポレイテッド | Portable fluorescence detection system and microassay cartridge |
| US10518262B2 (en) | 2012-12-21 | 2019-12-31 | Perkinelmer Health Sciences, Inc. | Low elasticity films for microfluidic use |
| WO2014152656A1 (en) | 2013-03-14 | 2014-09-25 | Cheng Kasing | Test strip housing system |
| EP2994543B1 (en) | 2013-05-07 | 2018-08-15 | Micronics, Inc. | Device for preparation and analysis of nucleic acids |
| WO2014182844A1 (en) | 2013-05-07 | 2014-11-13 | Micronics, Inc. | Microfluidic devices and methods for performing serum separation and blood cross-matching |
| WO2014182831A1 (en) | 2013-05-07 | 2014-11-13 | Micronics, Inc. | Methods for preparation of nucleic acid-containing samples using clay minerals and alkaline solutions |
| FR3012982B1 (en) * | 2013-11-08 | 2015-12-25 | Espci Innov | METHOD FOR STORING AND CONCENTRATING A VOLATILE COMPOUND |
| US9383352B2 (en) | 2014-03-26 | 2016-07-05 | Diabetomics, Inc. | Salivary protein glycosylation test for diagnosis and monitoring of diabetes |
| DK3126486T3 (en) | 2014-04-02 | 2019-10-14 | Chembio Diagnostic Systems Inc | IMMUNASSAY USING THE Catch Conjugate |
| US20160116466A1 (en) | 2014-10-27 | 2016-04-28 | Chembio Diagnostic Systems, Inc. | Rapid Screening Assay for Qualitative Detection of Multiple Febrile Illnesses |
| US20180011088A1 (en) | 2015-01-29 | 2018-01-11 | Neogen Corporation | Methods for Immuno Chromatographic Assay Desensitization |
| US9927443B2 (en) | 2015-04-10 | 2018-03-27 | Conquerab Inc. | Risk assessment for therapeutic drugs |
| CA2983732A1 (en) | 2015-04-23 | 2016-10-27 | Board Of Regents Of The Nevada System Of Higher Education, On Behalf Of The University Of Nevada, Reno | Fungal detection using mannan epitope |
| CN108136051A (en) | 2015-08-04 | 2018-06-08 | Cd诊断股份有限公司 | The method for detecting bad local organization reaction (ALTR) necrosis |
| AU2016340125B2 (en) | 2015-10-15 | 2021-12-09 | Inbios International, Inc. Disabled | Multiplexed lateral flow assay systems and methods for their use |
| EP3371321A1 (en) | 2015-11-06 | 2018-09-12 | Oslo Universitetssykehus HF | Methods and devices for detecting methanol poisoning using formate oxidase |
| US11208649B2 (en) | 2015-12-07 | 2021-12-28 | Zymergen Inc. | HTP genomic engineering platform |
| BR112018011503A2 (en) | 2015-12-07 | 2018-12-04 | Zymergen Inc | corynebacterium glutamicum promoters |
| US9988624B2 (en) | 2015-12-07 | 2018-06-05 | Zymergen Inc. | Microbial strain improvement by a HTP genomic engineering platform |
| KR102006320B1 (en) | 2015-12-07 | 2019-08-02 | 지머젠 인코포레이티드 | Microbial Strain Improvement by HTP Genome Engineering Platform |
| EP3387154A4 (en) | 2015-12-09 | 2019-05-15 | Intuitive Biosciences, Inc. | Automated silver enhancement system |
| WO2017147186A1 (en) | 2016-02-22 | 2017-08-31 | Ursure, Inc. | System and method for detecting therapeutic agents to monitor adherence to a treatment regimen |
| USD825075S1 (en) | 2016-02-23 | 2018-08-07 | Flora Bioscience, Inc. | Test strip holding device |
| US9903866B2 (en) | 2016-04-05 | 2018-02-27 | Conquerab Inc. | Portable devices for detection of antibodies against therapeutic drugs |
| WO2017178554A1 (en) | 2016-04-13 | 2017-10-19 | INSERM (Institut National de la Santé et de la Recherche Médicale) | Methods and kits for the rapid detection of the escherichia coli o25b-st131 clone |
| EP3232197A1 (en) | 2016-04-15 | 2017-10-18 | LIONEX Diagnostics and Therapeutics GmbH | A novel substrate and device for detecting an analyte and method for rapid diagnosis |
| JP2019519242A (en) | 2016-06-30 | 2019-07-11 | ザイマージェン インコーポレイテッド | Method for generating a bacterial hemoglobin library and its use |
| KR102345898B1 (en) | 2016-06-30 | 2022-01-03 | 지머젠 인코포레이티드 | Methods for generating glucose permeabilization enzyme libraries and uses thereof |
| US11061026B2 (en) | 2017-02-17 | 2021-07-13 | MFB Fertility, Inc. | System of evaluating corpus luteum function by recurrently evaluating progesterone non-serum bodily fluids on multiple days |
| WO2018203145A1 (en) | 2017-05-03 | 2018-11-08 | Oslo Universitetssykehus Hf | Systems and methods for monitoring biological fluids |
| WO2018213796A1 (en) | 2017-05-19 | 2018-11-22 | Zymergen Inc. | Genomic engineering of biosynthetic pathways leading to increased nadph |
| WO2018226893A2 (en) | 2017-06-06 | 2018-12-13 | Zymergen Inc. | A high-throughput (htp) genomic engineering platform for improving saccharopolyspora spinosa |
| WO2018226880A1 (en) | 2017-06-06 | 2018-12-13 | Zymergen Inc. | A htp genomic engineering platform for improving escherichia coli |
| JP7227162B2 (en) | 2017-06-06 | 2023-02-21 | ザイマージェン インコーポレイテッド | HTP Genome Engineering Platform for Improving Fungal Strains |
| JP2020524494A (en) | 2017-06-06 | 2020-08-20 | ザイマージェン インコーポレイテッド | High throughput transposon mutagenesis |
| WO2019152657A1 (en) | 2018-02-03 | 2019-08-08 | Simple Healthkit, Inc. | Reliable, comprehensive, and rapid sexual health assessment |
| EP3768844A4 (en) | 2018-03-20 | 2021-12-15 | Zymergen Inc. | A htp platform for the genetic engineering of chinese hamster ovary cells |
| CA3116909A1 (en) | 2018-10-24 | 2020-04-30 | Orasure Technologies, Inc. | Lateral flow assays for differential isotype detection |
| US11300576B2 (en) | 2019-01-29 | 2022-04-12 | Arizona Board Of Regents On Behalf Of Arizona State University | DARPin reagents that distinguish Alzheimer's disease and Parkinson's disease samples |
| WO2020210446A1 (en) | 2019-04-12 | 2020-10-15 | Dyax Corp. | Lateral flow immunoassay for measuring functional c1-esterase inhibitor (c1-inh) in plasma samples |
| KR20200132117A (en) | 2019-05-15 | 2020-11-25 | 정유한 | Optical Extracorporeal Diagnostic Device and Diagnostic Method using the Device |
| KR102264336B1 (en) | 2019-05-20 | 2021-06-14 | 정유한 | Optical Extracorporeal Diagnostic Device and Diagnostic Method using the Device |
| JP7258698B2 (en) * | 2019-09-06 | 2023-04-17 | 大日本塗料株式会社 | Method for detecting particulate matter by immunochromatographic method and kit therefor |
| GB2604367A (en) | 2021-03-03 | 2022-09-07 | Biotip Ltd | Devices and methods for performing lateral flow tests |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4094647A (en) * | 1976-07-02 | 1978-06-13 | Thyroid Diagnostics, Inc. | Test device |
| US4517288A (en) * | 1981-01-23 | 1985-05-14 | American Hospital Supply Corp. | Solid phase system for ligand assay |
| US4446232A (en) * | 1981-10-13 | 1984-05-01 | Liotta Lance A | Enzyme immunoassay with two-zoned device having bound antigens |
| US4435504A (en) * | 1982-07-15 | 1984-03-06 | Syva Company | Immunochromatographic assay with support having bound "MIP" and second enzyme |
| DE3484505D1 (en) * | 1983-12-19 | 1991-05-29 | Daiichi Pure Chemicals Co Ltd | IMMUNTEST. |
| US4703017C1 (en) * | 1984-02-14 | 2001-12-04 | Becton Dickinson Co | Solid phase assay with visual readout |
| DE3445816C1 (en) * | 1984-12-15 | 1986-06-12 | Behringwerke Ag, 3550 Marburg | Flat diagnostic agent |
| EP0243471A4 (en) * | 1985-10-22 | 1989-07-11 | Cooper Lipotech Inc | Solid-phase liposome immunoassay system. |
| GB8526741D0 (en) * | 1985-10-30 | 1985-12-04 | Boots Celltech Diagnostics | Binding assay device |
| GB8618443D0 (en) * | 1986-07-29 | 1986-09-03 | Univ London | Monoclonal antibodies |
-
1987
- 1987-05-13 US US07/049,328 patent/US4855240A/en not_active Expired - Lifetime
-
1988
- 1988-03-23 CA CA000562173A patent/CA1317863C/en not_active Expired - Fee Related
- 1988-04-06 AU AU14197/88A patent/AU609795B2/en not_active Ceased
- 1988-04-14 AT AT88303376T patent/ATE69311T1/en not_active IP Right Cessation
- 1988-04-14 ES ES198888303376T patent/ES2027760T3/en not_active Expired - Lifetime
- 1988-04-14 DE DE8888303376T patent/DE3866011D1/en not_active Expired - Fee Related
- 1988-04-14 EP EP88303376A patent/EP0291176B1/en not_active Expired - Lifetime
- 1988-05-06 KR KR1019880005263A patent/KR900005482B1/en not_active IP Right Cessation
- 1988-05-11 FI FI882205A patent/FI88965C/en not_active IP Right Cessation
- 1988-05-12 JP JP63115951A patent/JPH0718876B2/en not_active Expired - Lifetime
- 1988-05-13 DK DK265688A patent/DK265688A/en not_active Application Discontinuation
-
1991
- 1991-11-07 GR GR91401615T patent/GR3003073T3/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| GR3003073T3 (en) | 1993-02-17 |
| KR880014370A (en) | 1988-12-23 |
| FI882205A (en) | 1988-11-14 |
| DK265688A (en) | 1988-11-14 |
| EP0291176B1 (en) | 1991-11-06 |
| FI882205A0 (en) | 1988-05-11 |
| US4855240A (en) | 1989-08-08 |
| JPH0718876B2 (en) | 1995-03-06 |
| DK265688D0 (en) | 1988-05-13 |
| ATE69311T1 (en) | 1991-11-15 |
| AU1419788A (en) | 1988-11-17 |
| JPS63305252A (en) | 1988-12-13 |
| EP0291176A1 (en) | 1988-11-17 |
| ES2027760T3 (en) | 1992-06-16 |
| AU609795B2 (en) | 1991-05-09 |
| DE3866011D1 (en) | 1991-12-12 |
| KR900005482B1 (en) | 1990-07-30 |
| FI88965B (en) | 1993-04-15 |
| FI88965C (en) | 1993-07-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1317863C (en) | Solid phase assay employing capillary flow | |
| US6194220B1 (en) | Non-instrumented assay with quantitative and qualitative results | |
| US5998221A (en) | Non-instrumented assay with quantitative and qualitative results | |
| CA1303983C (en) | Solid phase assay | |
| AU707803B2 (en) | Liposome-enhanced immunoaggregation assay and test device | |
| US5789154A (en) | Liposome-enhanced immunoassay and test device | |
| EP0310862B1 (en) | Process, test device, and test kit for a rapid assay having a visible readout | |
| CA1312544C (en) | Chromatographic binding assay devices and methods | |
| US4703017A (en) | Solid phase assay with visual readout | |
| USRE38430E1 (en) | Solid phase chromatographic immunoassay | |
| US6057165A (en) | Quality control procedure for membrane flow-through diagnostic assay devices | |
| JPH0627738B2 (en) | Specific binding assay device and method | |
| US4752572A (en) | Lipid vesicles containing labeled species and their analytical uses | |
| US5851777A (en) | Homogeneous sol-sol assay | |
| US5567591A (en) | Amplified assay for analyte | |
| EP0302673B1 (en) | system and process for a visible assay for analyte | |
| WO1994012879A1 (en) | Dry reagent three element analyte detection system | |
| US5260025A (en) | Depositing a binder on a solid support | |
| CA1340069C (en) | Depositing a binder on a solid support |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |