EP0612403A1 - Connection-type treatment system for micro solution and method of treatment - Google Patents

Abstract

The invention relates to an apparatus (100) and a method associated with a connection type fluid transfer and processing system for efficiently and continuously performing the transfer and processing operations of small quantities of sample solutions. , without loss of substantial transfer. For this purpose, a first tube (110a) is used having a first open end (112a) and a second closed end, a second tube (110b) substantially of the same shape as the first tube and also having a first open end (112b). and a second closed end, as well as a set of fittings (126) for connecting the open end (112a) of the first tube (110a) to the open end (112b) of the second tube (110b). The assembly of fittings (126) comprises a membrane support holder with orifice (134), which serves to removably receive the chemically or biologically treated membranes (156), in order to apply a predetermined treatment to a solution, while passing the sample solution from the first tube (110a) to the second tube (110b). The sample is generally filtered through the membrane (156) by centrifugation. A special adapter (170) is provided for receiving and retaining the transfer system (100) during centrifugation. Such a system (100) makes it possible to handle quantities of reactive solutions of the order of microliter during analyzes, treatments and biochemical assays without using micropipettes, without the usual loss of solution.

Description

Specification

Connection-Type Treatment System for Micro Solution and Method of Treatment

BACKGROUND OP THE INVENTION Field of the Invention The present invention relates to a connection-type transfer and treatment system and method for micro solutions capable of performing efficient and continuous transfer and/or treatment of a small amount of sample solution.

Brief Description of the Prior Art Conventionally, studies in the fields of analytical biochemistry and clinical chemistry have been generally made on the basis of working with sample treatment solutions of milliliter amounts. With recent development of biotechnology and immunochemistry, however, the studies in these fields are made on the basis of results of treatment of sample solutions of size on the order of icroliters. As the treatment unit of the sample solution becomes smaller, the following are becoming problems. In the analysis of biological samples by high performance liquid chromatography (HPLC) , high performance capillary zone electrophoresis or many other techniques, pretreatment of a samples prior to analysis is often required. In other cases, two or more enzymatic digestions must be conducted in succession to obtain the desired products. In such instances, it is necessary for the sample solution, obtained by an enzyme reaction in a reaction tube, to be filtered through an ultrafiltration membrane to remove molecules having larger molecular weights or insoluble fine particles in order to prevent clogging of the high performance liquid chromatography columns. Typically, an instrument, such as for example a micropipet, is used to transfer the sample solution from the reaction tube into another device for ultrafiltration. In this method, however, a certain amount of loss of the sample is inevitable in the process of transferring the sample solution. The loss is greater when the sample quantities are smaller. In another example, a protein may be labeled using radioisotopes, and then the labeled protein constituent and the isotopes should be separated. In such cases, it is conventional that, after labeling with the isotope in a reaction tube, part or all of the sample solution is transferred, by micropipet or the like, into a device for radiation measurement. Accordingly, the above-described problem of loss of the sample also arises in the process of transferring the sample solution. Also, the risk of radiation contamination of instruments used in liquid transfer cannot be avoided. Furthermore, when carrying out sample handling procedures which by their nature require a plurality of steps, such as the enzyme reaction and the sample radio- isotope labeling procedures described above, the problems associated with the amount of sample loss and degree of instrument contamination get progressively worse, since these sample handling procedures require multiple transfers of the sample.

SUMMARY OF THE INVENTION The invention comprises a connection type treatment system and method for micro solution transfer which includes: 1) a first container (source or reaction tube) having a tubular shape with a first end open and an opposed second end closed, in which a reaction of a sample solution takes place; 2) a second container (target tube) of substantially the same shape as the first container with one end opened and the other end closed; and 3) a connector assembly for connecting the open end of the first container and the open end of the second container, and also for applying predetermined treatment while passing the sample solution from the first container (source tube) to the second container (target tube) . The connector assembly includes a connector member having a central through bore adapted to receive a membrane support containing a ultra filtration membrane. A stopper fits within the membrane support to hold the membrane in place. In an alternate embodiment, the membrane support is formed integral with the connector. According to another aspect of the present invention, a method of treating micro solutions, using a connection type treatment system for micro solutions, includes the steps of executing a reaction of the sample solution inside the first container, connecting the open end of the second container to the open end of the first container using the connector assembly, turning the connected first and second containers upside down, and applying predetermined treatment using the connector assembly while passing the sample solution from the first container into the second container. At least one screw-on cap is provided for sealing either or both the source and/or target tubes. The present invention permits simultaneous transfer of a sample solution between containers as well as a predetermined treatment of the solution using two containers and a specially adapted connector assembly for connecting these containers. Accordingly, use of transferring instruments, such as a micropipet, are not required, and the problems of sample loss and contamination risk are substantially reduced or minimized.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram of a connection-type transfer and treatment system and method for micro solutions. Fig. 2 is partial sectional view illustrating a specific structure of a centrifugal connection-type micro solution transfer and treatment device constructed in accordance with a first embodiment of the present invention. Figs. 3a-3b is a series of diagrams illustrating the structure of the tube 10 shown in Fig. 2. Figs. 4a-4b is a series of diagrams illustrating structure of the dual tube connector 16 shown in Fig. 2. Fig. 5 is a four part series diagram illustrating structure of the filter element supporting member 22 shown in Fig. 2. Figs. 6a-6b is a series of diagrams illustrating structure of the stopper 34 shown in Fig. 2. Fig. 7 is partial sectional view of a centrifugal connection-type micro solution transfer and treatment system constructed in accordance with a second embodiment of the present invention. Fig. 8 is a partial section view of a tube of the second embodiment micro solution transfer/treatment device of Fig. 7 shown here provided with a screw-on cap 122. Fig. 9 is a cross-sectional exploded view of the second embodiment micro solution transfer/treatment device of Fig. 7 shown with the upper or source tube 110b omitted. Fig. 10 is a top end view of the stopper 150 of the second embodiment micro solution treatment device of Fig. 7 taken along the line and in the direction of arrows 10- 10 of Fig. 9. Fig. 11 is an isometric view of the stopper 150 of the second embodiment device of Fig. 7. Fig. 11a is a perspective view of a tool 162 for inserting the stopper 150 into the inner cylinder 130 of the connector 126. Fig. 12 is a top end view of the connector 126 of the second embodiment micro solution treatment device illustrating the membrane support region of the connector. Fig. 13 is a fragmentary cross section view of the membrane support region of the connector of the second embodiment micro solution treatment device taken along the line and looking into the direction of arrows 13-13 of Fig. 12. Fig. 14 is a side elevation view of an adapter 170 used for securing the second embodiment for the microsolution treatment device of the present invention in a centrifuge rotor. Fig. 15 is a side elevation view in cross section of the adapter 170 of Fig. 14. Fig. 16 is an isometric view illustrating how the second embodiment micro solution treatment device fits within the adapter (shown in cross-section) . Fig. 17 is a functional schematic view in partial cross-section of the second embodiment micro solution treatment device of the present invention held by the adapter and positioned in a fixed angle rotor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description illustrates the invention by way of example, not by way of limitation of the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what Applicant presently believes is the best mode of carrying out the invention. Fig. 1 is a diagram which describes in schematic fashion the overall system principles and method steps for the connection-type micro solution transfer and treatment system and method of the present invention. The presently preferred embodiments of the present invention relate to a treatment system and method for pretreat ent of solutions for high performance liquid chromatography (HPLC) using an ultrafiltration membrane. Referring to Fig. 1 (a) , a researcher first carries out a predetermined chemical reaction such as, for example, an enzyme reaction, in a container or tube A schematically shown in Fig. 1 (a) . The resulting solution or product is designated by oblique lines in Fig. 1. A cap (not shown) may be used on the open end of the tube. Next, as is shown in Fig. 1 (b) , at the end of the reaction, the experimenter then removes a cap (not shown) from tube A and attaches one end of a connector C to the tube A opening. A second container, indicated in the drawing as container or tube B, having substantially the same shape as tube A, is connected in upside-down fashion to the other side of the connector C. The connector C includes an ultrafiltration membrane (not shown) therein. Next, as shown in Fig. 1 (c) , the treatment system integrally formed of two tubes A, B and connector C is inverted, as shown by the intertwined arrows, and inserted in a centrifugal separator D, and then the centrifugal separator is spun. In this example, tube A is referred to as the "source tube" or "reaction tube" and tube B is referred to as the "target tube". As a result of the centrifugation, as shown in Fig. 1 (d) , the sample solution inside reaction (source) tube A passes through the ultrafiltration membrane included inside connector C into the target tube B. Molecules, stripped of solvent, having predetermined or larger molecular weights are trapped by the ultrafiltration membrane. As described above, according to several embodiments of the present invention, the centrifugation is executed with the reaction tube containing the sample solution and the tube for the centrifugation treatment being integrally connected with the connector having an ultrafiltration membrane therein. Therefore, by eliminating the need for use of a micropipet to transfer the solution between source and target tubes, there is no solution loss due to solution remaining in the micropipet instrument. Also, possible contamination of the pipet is avoided. Further, as compared to when solution transfer is performed by a "direct pour" method whereby the contents of the reaction (source) tube are poured into the target tube, virtually no sample solution residue remains on the inner source tube wall in the present invention in view of the completeness afforded by filtration through centrifugation. When executing a reaction in a plurality of steps, the treatment in the above figures 1 (a) - (d) may be repeated in each step after the second step using tube B (originally the target tube) , now containing the filtered solution (Fig. 1 (d) ) , as the new reaction (source) tube A', and adding a new target tube B', and so on. Fig. 2 is a partial sectional view of a micro solution transfer/treatment system apparatus constructed in accordance with a first embodiment of the present invention. The micro solution treatment system apparatus 1 is illustrated in a connected state corresponding to the schematic representations of Figs, l (c) and (d) . The micro solution treatment system apparatus 1 comprises reaction or source tube 10a and target tube 10b, each having an open end 12a, 12b oriented opposed facing one another and joined together by a connector assembly 16. The tubes 10a, 10b are similarly shaped and are preferably fabricated from a known plastic material of the type commonly used in micro-centrifuge applications, such as for example, polypropylene or polyethylene. The tubes 10a, 10b correspond to the tubes A and B of Fig. 1, respectively, and the connector assembly 16 corresponds to the connector C of Fig. 1. The connector assembly 16 comprises a connector member 17, a membrane support 22, and a stopper 34. The connector member or connector 17 is provided with two different connector ends for engagement with the tube openings 12a, 12b of the respective tubes 10a, 10b including a first connector end 18 defined as an open mouth-type member having tapered receiving inner walls 19 dimensioned for snug, slip-fit engagement with an outer peripheral wall 14a, 14b of a corresponding tube opening 12a or 12b, and a second connector end 20 having a male screw portion 19 provided along its outer peripheral wall for engagement with a corresponding female screw portion 15a, 15b provided to an inner peripheral wall of a corresponding tube opening 12a, 12b. In Fig. 2, the connector 17 is shown having its first connector end 18 fitted over the outer peripheral wall 14a of tube opening 12a of the source tube 10a, while the male screw portion 19 of the second connector end 20 threadingly engages the inner female screw portion 15b of tube opening 12b of the target tube 10b. The membrane support 22 is provided with a male screw portion 24 formed along an outer peripheral wall and having threads sized for receivingly engaging the threads of the inner peripheral wall female screw portions 15a, 15b of a tube opening 12a, 12b. In this example, the outer peripheral wall male screw portion 24 of membrane support 22 engages the inner peripheral wall female screw portion 15a of the source tube opening 12a. The membrane support 22 is adjusted for receiving an ultrafiltration membrane 30 placed along a bottom supporting surface 26 thereof (See Fig. 5) . A stopper 34 is provided for ensuring that the membrane remains fixed within the membrane support 22. Fig. 3 is an enlarged two view diagram showing in more detail the structure of the tube 10. In this case tube 10 may be either source tube 10a or target tube 10b. In Fig. 3, part (a) is a plan view of the tube 10 looking into the tube opening 12, and part (b) is a cross-section view showing the flat outer peripheral wall 14 and female screw portion inner peripheral wall 15 of the tube opening 12. The wall thickness "t" of the tube opening 12 preferably tapers slightly towards its free end to permit ease of insertion within the receiving connector end 18 of the connector member 17. Fig. 4 is an enlarged two view series diagram showing structure of the connector 17 of Fig. 2 wherein part (a) is a plan view and part (b) is a cross-section view. The connector 17 is generally circular in cross section and includes an inner stop surface or ledge 19 against which end portions of the tube opening 12 and membrane support 24 are constrained in abutting engagement when the system apparatus 1 is fully connected together (see Fig. 2) . The connector 17 is provided with a central bore hole 23 for permitting transfer of solution material from a first tube to a second tube connected thereto. Fig. 5 is an enlarged four view series diagram illustrating the structure of the membrane support member 22 of Fig. 2 wherein part (a) is a top plan view (supporting surface 26 omitted) ; part (b) is a cross sectional view; part (c) is a side elevation view; and part (d) is an enlarged bottom plan view showing the configuration of a plurality of through holes or ducts 28 formed in the bottom wall 26 shown in part (a) . Note, for purposes of clarity, the ducts 28 are not shown in the cross sectional view of part (b) . Fig. 6 is a two view series diagram illustrating structure of tubular stopper 34 of Fig. 2 wherein part (a) is a side elevation view, and part (b) is a top plan view. Stopper 34 resembles a ring or tubular member and includes a circumferential rib 36 provided on its outer peripheral wall 38 which is adapted for snap fit insertion within a corresponding convex groove 27 provided to the inner peripheral wall 29 of the membrane support 22 (see Fig. 5) . Combination of two tubes 10a and 10b as described above can simultaneously achieve efficient transfer of solutions and the centrifugation treatment as shown in Fig. 1. Figs. 7-13 illustrate a second embodiment for the miσrosolution/transfer treatment system apparatus of the present invention which is designated generally as element 100 in the drawings. Referring to Fig. 7, the second embodiment 100 for the microsolution treatment system apparatus comprises two similarly shaped containers or tubes 110a, 110b each having an open end 112a, 112b which in use are connected together by a connector assembly 126. The connector assembly 126 of the second embodiment comprises two principle elements including a connector/filter retainer member 127 and a stopper 150. As is best seen in Figs. 7 and Fig. 9, the connector member 127 is formed as a bi-annular structure having an outer perimeter cylindrical shell portion or sleeve 128 surrounding an inner cylinder portion 130 and connected integrally thereto by a lateral, radially extending web 132. The outer shell (sleeve) 128 and inner cylinder define two connector ends including a first threaded connector end 136 and a second slip-on connector end 140. The outer shell portion or sleeve 128 is preferably serrated or knurled at 137 to facilitate handling by a user. Similar grip facilitating surfaces 120a, 120b may be provided to the outer surfaces of the tubes 110a, 110b. In this example, the threaded connector end 136 includes female screw threads disposed along an inner peripheral wall of the outer cylindrical portion 128 adapted to engage the male screw threads 114a disposed along the outer peripheral wall of the tube opening 112a of tube 110a. Also, the slip on connector end 140 fits over the open end 112b (and the male threads 114b) of the target tube 110b. The inner cylinder portion 130 of the connector 127 also includes a transverse membrane support surface or region 134. In use, the connector member 127 is attached to the tube opening such that the membrane supporting inner cylinder 130 is oriented to fit within the tube opening 112b of the target tube 110b. The membrane support surface 134 of the inner cylinder 130 defines a foramenous plate on which the ultrafiltration membrane 156 rests. The ultrafiltration membrane 156 is tightly held in place by a stopper 150 which fits within the inner cylinder 130 during use. The preferred height dimension of the wall for the tubular stopper 150 and inner cylinder 130 is sufficiently high to ensure that all solution remains within the cylindrical volume defined by the bore of tubular stopper 150 during centrifuge operation such that a meniscus, which represents loss of solution, is not permitted to form above the stopper 150 or cylinder 130. This volume or capacity is typically on the order of 500 μl to 600 μl for microsolution work. Also, the wall height of the stopper 150 is preferably slightly less than the surrounding wall portion of the inner cylinder 130 so that the inwardly tapered ends 158 of the stopper 150 form a gradual transition to promote full flow of fluid in the downward direction from the source tube into the target tube during centrifuge operation. Also, the end walls forming the mouth opening of the inner cylinder 130 are preferably provided with a slight chamfer at 166 (see Fig. 9) to further promote complete flow of fluid down into the inner cylinder 130. Fig. 8 shows a single tube 110 having a screw top cap 122 for threading onto the outer male screw threads 114 of the tube opening 112. The cap 122 includes an O- ring 124 to ensure against fluid loss. The screw on cap 122 is useful for sealing a source tube 110a, such as for example after an enzyme reaction has occurred, or for sealing a target tube after the desired treatment for the microsolution has been obtained. Referring to Figs. 9-11, the stopper 150 includes plurality of notched relieved portions 160 spaced equidistant along the top perimeter wall 154. These notched portions 160 facilitate press fit insertion of the stopper within the inner cylinder membrane support 130 of the connector assembly 126. The stopper 150 preferably includes a longitudinal groove (not shown) formed along its outer cylindrical wall to facilitate air exchange and thereby relieve any trapped air within the inner cylinder membrane support 130 and the stopper 150 when the stopper 150 is fitted within the membrane inner cylinder membrane support 130. Fig. 11a illustrates an example tool 162 useful for inserting the stopper 150 within the inner cylinder 130. The tool 162 preferably includes axially extending peripheral tab members 164 for engaging the notched relieved portion 160 of the tubular stopper 150. The top perimeter edge 154 of the stopper 150 is preferably tapered at 158 to ensure that all microsolution drains towards the ultrafiltration membrane during use and does not get trapped above the stopper perimeter edge 154. Similarly, all the edges contours of the notches 160 are preferably rounded to promote and ensure fluid flow. Figs. 12 and 13 illustrate in more detail the generally foramenous plate-like membrane support region 134 of the inner cylinder 130 of the connector 127. The porous plate region 134 includes a plurality of arcuate and semi-arcuate through holes or ducts 142 interspaced by ribs or land portions 144. At its outer periphery the membrane's support region of foramenous plate 134 includes a slightly upraised rib member 146 having a peak disposed coordinately aligned with lower end wall 152 of the tubulcir stopper 150 when the stopper 150 is fitted within the inner cylinder 130. This is best seen with reference to Fig. 13 (stopper 150 and membrane 152 are indicated in phantom) . In this way, the membrane 156 is maintained taut and prevented from moving by the engagement of the bottom end wall 152 stopper against the upraised rib member 146. Figs. 14-16 show an adapter 170 which may be used for fitting the first or second embodiments of the microsolution transfer/treatment system 100 within a receiving socket of a centrifuge rotor. In view of the added circumferential girth provided by its additional connecting elements, the microsolution treatment system has a slightly increased outer radius as compared to conventional centrifuge tubes. Accordingly, a wider diameter socket in a centrifuge rotor is preferably provided for receiving the dual tube/connector system. For this purpose an adapter 170 is provided to ensure proper fit and support of the microsolution system 100 within the centrifuge rotor. The adapter 170 is generally cylindrical in cross section and has an inner diameter sized for a close tolerance fit with the connection-type microsolution system when inserted in it. The outer surface of the adapter 170 is provided with a laterally extended circumferential ledge member 174 (an annular flange) , which acts as a stop member and rest support when fitted into a receiving socket 176 of a centrifuge rotor. Fig. 17 shows the system apparatus 100 placed within the adapter 170 and inserted within an appropriate receiving socket or hole 176 of a rotor 178. The adapter includes at its bottom end a reduced radius opening 180 sized to engage an outer portion of one of the tubes of the microsolution system 100 at a location along the bottom tube adjacent the connector assembly, such that the bottom end 182 of the system apparatus 100 is prevented from contacting a base portion 184 or side wall 185 of the centrifuge rotor 178. The upstanding walls 186 of the adapter 170 above the ledge member 174 are of sufficient length to ensure adequate support of the connection-type microsolution treatment system apparatus during centrifuge operation. As is best seen in Fig. 16 the forward portion of the adapter may be cut away (indicated in phantom) at 188, thereby leaving only a high back supporting portion of the upper adapter walls above the annular flange or ledge member 174. (The cut away portion is indicated as element 171.) In this way, a lightweight adapter having sufficient support for reducing stresses placed on the system apparatus from centrifuged forces is achieved. Although the above-described embodiment concerns a system for pretreatment of high performance liquid chromatography in which an ultrafiltration membrane is provided in a connector portion, in another embodiment of the present invention a pretreatment system utilizing affinity can be implemented by providing an affinity functional membrane in the connection. For example, the connector membrane may contain antibody or antigens and lectins or an ion-exchange membrane, or a membrane having other suitable functions. Although the present invention has been described and illustrated in detail, it should be understood that various modifications within the scope of this invention can be made by one of ordinary skill in the art without departing from the spirit thereof. I therefore wish my invention to be defined by the scope of the appended claims in view of the specification as broadly as the prior art will permit.

What is claimed is:

Claims

CLAIMS 1. A connection-type transfer and treatment system for micro solutions comprising in operative combination: a) a first container of a generally tubular shape having a first open end and a second closed end, said first container adapted to contain a sample solution therein; b) a second container having substantially the same shape as said first container and having a first open end and a second closed end; c) connector means for connecting the open end of said first container to the open end of said second container; and d) means for retaining a membrane for filtering or/and applying a predetermined treatment to said sample solution while passing said sample solution from said first container into said second container, said membrane retaining means disposed internal of said connecting means to contact fluid passing from said first to said second container.

2. A connection-type treatment system for micro solutions as in claim 1 wherein: a) said connecting means is reversibly connectable for exchanging the position of said first and second containers to permit successive treatments to the micro solution while passing between said first and second containers.

3. A connection-type treatment system for micro solutions as in claim 2 wherein: a) each of said containers includes threads disposed along a peripheral wall surface adjacent its open end; and b) said connecting means is a connector assembly for mechanically connecting said first and second containers and wherein said connector assembly includes: i) a sleeve member having a first connector end for slip fit connection with said open end of either said first or second containers, and a second end including threads for engagement with said threads of the other one of said first or second container open ends; ii) a membrane support adapted for fitted insertion within said sleeve connector member adjacent said first connector end and having a central base for passing micro solution therethrough and a generally flat foramenous surface for retaining said membrane means; and iϋ) means for securing said membrane means to said membrane support in a manner to provide a liquid tight seal between the periphery of said membrane support and said membrane means.

4. A connection-type treatment system for micro solutions as in claim 3 wherein said membrane support includes threads along an outer peripheral wall thereof for threaded engagement with an unoccupied one of said screw means of either said first or second container located on the interior wall of said containers adjacent the open ends thereof.

5. A connection-type treatment system for micro solutions as in claim 4 wherein said membrane means is an ultrafiltration membrane and said securing means for said membrane means is a stopper member in the shape of a ring having an outer surface configuration adapted for snap fit insertion within said central cavity of said membrane support.

6. A connection-type treatment system for micro solutions as in claim 2 wherein; a) each of said containers includes threads disposed along a peripheral wall surface adjacent its open end; b) said connecting means is a connector assembly for mechanically connecting together said first and second containers wherein said connector assembly includes a connector member including an outer sleeve portion and integrally attached inner tubular membrane support, said connector member having a first connector end for slip fit connection with said open end of either said first or second containers and a second connector end including threads or engagement of said threads of the other one of said first or second container open ends; said membrane support includes a generally flat foramenous surface for receiving said membrane means; and means for securing said membrane means to said membrane support in a manner to provide a liquid tight seal between a periphery of said membrane support and said membrane means and to minimize retention of fluid in said connector and said first container.

7. A connection-type treatment system for micro solutions as in claim 6 wherein: a) said securing means for said membrane means includes a generally tubular stopper member adapted for fitted insertion within said membrane support and having a bottom end wall co-aligned with an upraised perimeter rib member provided to said foramenous surface of said membrane support for pinning said membrane means to said membrane support.

8. A connection-type treatment system for micro solutions as in claim 7 which includes an ultrafiltration membrane and wherein said outer surface portions of said first and second containers and said outer sleeve of said connector member are knurled to facilitate handling by a user.

9. A connection-type treatment system for micro solutions comprising in operative combination: a) a first container of a generally tubular shape having a first open end and a second closed end, said first container is adapted to retain a sample solution therein; b) a second container having a substantially similar shape as said first container and having a first open end and a second closed end; c) connector means for connecting the open end of said first container to the open end of said second container; d) means for retaining a membrane for filtering and/or applying a predetermined treatment to said sample solution while passing said sample solution from said first container into said second container, said membrane means disposed internal of said connecting means; e) a tubular adapter receivingly engaging at least said connector for properly positioning and supporting said dual container and connector assembly within a centrifuge rotor when said first and second containers are connected by said connector means; and f) an ultrafiltration membrane including a component for treating said solution during passage therethrough.

10. A method of transferring and treating micro solutions using a connection type micro solution treatment system which includes a pair of tubular containers of substantially similar shape, each container having one end opened and the other end closed, connector means for connecting the open ends of said containers together, and membrane means carried by said connector means for filtering and/or applying predetermined treatment to the micro solution, said method comprising the steps of: a) introducing a sample solution into a first of said container pair; b) emplacing an ultrafiltration membrane having a solution treatment component associated therewith in said connector; c) connecting the open end of a second container to the open end of a first container using said connector means with said first container being below said second container; d) inverting said connected pair of containers so that said sample solution can pass through said membrane into said second container therebelow; and d) treating said solution while passing the sample solution from said first container into said second container.

11. The treatment method as in claim 10 wherein said step of treating includes the steps of: a) placing said connection type treatment system for micro solution within a centrifuge rotor; and b) centrifuging until said micro solution from said irst container passes through said membrane means and is collected in said second container.