WO1993002348A1

WO1993002348A1 - Reagent handling system for automated clinical analyzer apparatus

Info

Publication number: WO1993002348A1
Application number: PCT/US1992/006024
Authority: WO
Inventors: Edwin M. Marker, Jr.; Raul O. Lasso; Laura A. Allen
Original assignee: Abbott Laboratories
Priority date: 1991-07-22
Filing date: 1992-07-21
Publication date: 1993-02-04
Also published as: JPH06509175A; AU2428092A; CA2102123A1

Abstract

A reagent handling system for automated clinical analyzer apparatus (20). The reagent handling system includes a plurality of reagent packs (22) each carrying one or more reagents (53) for performing a particular assay on a sample (12) in the apparatus (20), and a carousel (21) for supporting one or more of the plurality of reagent packs (22) in the apparatus. The reagent packs (22) each include machine-readable identification (83) thereon for permitting automatic identification in the analyzer (20) of the reagent pack (22) and its position on the carousel (21) whereby any selected one of the plurality of reagent packs (22) may be randomly placed at any position on the carousel (21) and be automatically identified to enable a particular assay to be automatically performed on the sample (12). The system of the invention significantly reduces both apparatus set-up time and the risk of operator error.

Description

REAGENT HANDLING SYSTEM FOR AUTOMATED CLINICAL ANALYZER APPARATUS

Background of the Invention

1. Field of the Invention

The present invention relates generally to a reagent handling system for automated clinical analyzer apparatus; and, more particularly, to a reagent handling system including a random access carousel for carrying a plurality of reagent packs in an automated clinical analyzer apparatus and a reagent pack therefor.

2. Description of the Prior Art

In the diagnostic testing of biological fluids, samples of body fluids, such as serum, plasma, urine and the like are assayed for the presence of analytes such as drugs, viruses or bacteria by reacting the samples according to a specific test protocol with specific reagents which are selected to identify a particular analyte. The protocol specifies the sequence in which sample and reagents are to be introduced, the timing for the introduction of sample and reagents, the volumes of each to be used, and other conditions to be controlled. The resulting reaction mixture is typically allowed to incubate for a predetermined time and is then read, optically or otherwise, to determine the presence and concentration of the specific analyte which the as_.ay is designed to identify. In general, procedures and apparatus for preparing and reading immunoassays are well-known and are not described in detail herein.

Frequently, the diagnostic testing of biological fluids is carried out in automated clinical analyzer apparatus which are capable of performing immunoassays on a plurality of samples simultaneously. In some automated analyzers, a batch of sample containers is 2 supported around the circumference of a rotatable carousel together with a corresponding number of reaction containers. The carousel is then mounted' inside the analyzer, and is rotated stepwise to move each sample container and reaction container pair first to a position adjacent a preparation station, and then to a second position adjacent a reading station. Mechanical apparatus having pipette means and typically operating under program control is located in proximity to the preparation station as are a plurality of reagent containers which contain the reagents required to perform a specific immunoassay on the batch of samples contained in the sample containers. The reagent containers may be individual containers or may be configured as a unitary reagent pack containing vials of the required reagents. Typically, the reagent containers contain sufficient amounts of each reagent to test a number of samples

At the preparation station, the mechanical apparatus and pipette means operate to access and transfer volumes of samples from the sample container and reagents from the reagent containers into a reaction container according to the protocol established for the specific assay; and when the mechanical apparatus completes the preparation of the reaction mixture according to the test protocol, the carousel rotates to position the next sample container and reaction container pair adjacent the preparation station and to move the previous pair toward the reading station.

One limitation of many known analyzers is that they are capable of performing only one assay at a time on each batch of samples on the carousel. In order to perform different assays, it is necessary to physically remove the reagent containers from the analyzer and replace them with different reagent containers for the next assay to be run. This procedure decreases analyzer throughput, increases the cost associated with performing the assays and increases the chance of error in conducting the assays.

One approach to solving this problem has been to provide a carousel for an automated analyzer which is adapted to receive and hold a selected plurality of reagent packs in selected positions on the carousel interspersed with a plurality of sample containers containing samples to be tested. This approach provides increased flexibility by permitting various possible tests to be carried out on the same or different samples. However, loading of the carousel is relatively time-consuming, and with the relatively large number of sample containers and reagent containers that must be mounted on the carousel, the risk of mounting the incorrect reagent containers or of inaccurately positioning the reagent containers on the carousel is substantial.

Summary of the Invention

The present invention provides a reagent handling system for automated clinical analyzer apparatus which overcomes the limitations and drawbacks associated with the prior art.

The reagent handling system includes a plurality of reagent containment means, each carrying one or more reagents for performing a particular assay on a sample in the apparatus; and a support means for supporting one or a plurality of the reagent containment means in the analyzer, the support means having a plurality of support positions for supporting the reagent containment means, wherein each of the plurality of reagent containment means includes identification means thereon for permitting automatic identification of each reagent containment means, whereby any selected one of the plurality of reagent containment means may be randomly positioned at any one of the support positions on the support means and be automatically identified by the identification means to enable the particular assay to be automatically performed on the sample with the one or more reagents in the selected reagent containment means.

With the reagent handling system of the present invention, an operator can randomly position each of the reagent containment means needed to perform a desired series of tests at any of the support positions on the support means quickly and easily without concern of inaccurate positioning. The apparatus will automatically identify the position of each reagent containment means on the support means by the identification means thereon to ensure that the desired assays are properly carried out. The set-up time for performing a series of assays is thus significantly reduced and apparatus throughput is significantly increased.

According to a presently preferred embodiment, the support means comprises a carousel having a plurality of support areas around its circumference for supporting the reagent containment means and which is adapted to be mounted in the analyzer in proximity to a means for automatically reading the identification means. The carousel includes means for rotating the carousel in a stepwise fashion to permit the identification means on each reagent containment means to be read by the reading means prior to running a series of assays to identify the position of each reagent containment means on the carousel. The identification means preferably comprises bar code means or other known machine-readable indicia.

The reagent containment means preferably comprises a reagent pack consisting of a housing supporting a plurality of reagent-containing vials, and the identification means is preferably applied to a surface of the housing. The reagent containment means and the carousel of the present invention preferably also include interlocking means for releasably mounting the reagent containment means at any support area on the carousel, and for permitting the reagent containment means to be quickly and easily mounted on or removed from the carousel as required. The carousel can carry any^' desired number of reagent containment means from one to, for example, eight or more as required for a particular run.

Specific details and further advantages of the invention will be set forth hereinafter in conjunction with the following detailed description of a presently preferred embodiment.

Brief Description of the Drawings

Fig. 1 schematically illustrates interior portions of an automated clinical analyzer apparatus incorporating a reagent handling system according to a preferred embodiment of the present invention;

Figs. 2, 3 and 4 are top, side and bottom views, respectively, of the random access carousel of the system of Fig. 1;

Fig. 5 is a perspective view schematically illustrating the overall appearance of a reagent pack of the system; and

Figs. 6, 7 and 8 are top, inner side and lateral side views, respectively, of the reagent pack housing to illustrate specific details thereof.

Detailed Description of the Preferred Embodiment

Fig. 1 schematically illustrates the interior of an automated clinical analyzer apparatus incorporating the reagent handling system according to a preferred embodiment of the present invention. Only that structure of the analyzer needed to provide a clear understanding of the present invention is illustrated and described herein. The analyzer is generally designated by reference number 20 and contains a sample carousel 10 adapted to contain a plurality of fluid samples, for example, biological fluids such as blood or like, to be tested. The samples are contained in a plurality of sample containers 12 of known type positioned around the circumference of the carousel 10. The carousel 10 may also include a plurality of reaction containers 15 and, as known to those skilled in the art, the carousel 10 is mounted for rotation in a stepwise fashion to move each sample container-reaction container pair to a first position adjacent a preparation station 13, and then to a second position adjacent a reaction mixture reading station 14.

A mechanical apparatus 16 which includes pipetting means and which typically operates under program control, is located in proximity to the preparation station and operates to transfer volumes of samples from the sample containers and reagents from reagent containers into reaction containers according to an established protocol for a particular test to be run. After the mechanical apparatus completes the preparation of the reaction mixture, the carousel 10 is rotated to position the next sample container-reaction container pair adjacent the preparation station and to move the previous pair toward the reaction mixture reading station 14 to be analyzed by suitable optics 17.

The apparatus also includes a reagent handling system comprising a reagent carousel 21 positioned adjacent the sample carousel 10. The reagent carousel 21 is adapted to support a plurality of reagent containment means or reagent packs 22, each containing a plurality of vials containing all the reagents needed for a particular assay. As will be explained hereinafter, the reagent carousel 21 is also mounted for rotation in a stepwise fashion so as to position a desired reagent pack 22 at the preparation station 13 to permit the mechanical apparatus 16 to transfer the reagents therein to a reaction container on carousel 10.

Also schematically illustrated in Fig. 1 is a reading means 25 for automatically reading identification means provided on the reagent packs to identify each reagent pack and its position on carousel 21 as will be explained hereinafter.

Figs. 2-4 are top, side and bottom views, respectively, of the reagent carousel 21 according to a presently preferred embodiment of the invention. The carousel 21 comprises a circular base 31 adapted to support a plurality of reagent packs 22 around the circumference thereof.

More particularly, as shown in Fig. 2., the base includes a plurality of spaced, radially extending ribs 32 which define a plurality of generally wedge-shaped areas 33 for receiving the plurality of reagent packs. In the embodiment illustrated in Figs. 2-4, eight areas are provided on the base to receive eight reagent packs. This is exemplary only, however, as the carousel can be designed to hold any desired number of appropriately shaped reagent packs thereon.

As best shown in Fig. 3, a knob or handle 34 extends upwardly from the center of the carousel to permit the carousel to be easily handled for placement on or removal from the analyzer and for mounting or removing the reagent packs therefrom.

Surrounding the base of the handle is a circular raised portion 36 which defines an outwardly facing shoulder 37 defining the inner edge of the wedge-shaped areas 33 on the base. A plurality of slots 38 are formed in the shoulder 37 with each slot being substantially centrally positioned between a pair of radial ribs 32 defining each wedge-shaped area. Each wedge-shaped area is preferably also identified with suitable indicia such as the letters A through H applied on the top surface of the raised portion 36 as shown in Fig. 2.

The outer periphery of the carousel base^'is provided with an upwardly extending rim 41 which defines the outer edge of the wedge-shaped areas. * A plurality of slots 42 are also provided in the base adjacent the rim 41 and, as shown in Fig. 2, the slots 42 are aligned with the radial ribs 32 on the base with each slot 42 extending into the areas 33 on either side of a rib.

As shown in Fig. 4, the bottom of the carousel 21 includes a central cylindrical recess 46 to rotatably mount the carousel to a spindle on the analyzer apparatus, and a plurality of drive slots or grooves 47 arranged in a circle around the base (only a few of the grooves are shown in the Fig.) . The plurality of grooves are adapted to be engaged by a suitable gear of a drive mechanism to rotate the carousel in stepwise fashion to position the reagent packs thereon at the preparation station 13 and adjacent the reading means 25 as will be explained hereinafter. The structure of the drive mechanism can be conventional and need not be described herein.

In addition, a tab 49 extends downwardly from the bottom surface to identify the "home" position of the carousel to permit the position of the carousel to be monitored by the overall analyzer control (schematically shown at 50 in Fig. 1) as it is rotated.

The reagent carousel 21 preferably comprises a molded plastic member formed of any suitable rigid plastic material.

Fig. 5 illustrates a reagent pack 22 for use with the reagent carousel 21 of the present invention. The reagent pack comprises a molded plastic housing 51 having a plurality of wells or cavities 52 for receiving a plurality of reagent-containing vials 53. The vials are preferably molded of a soft plastic material, but may also be formed of glass or other_, suitable material. The housing 51 is generally wedge-shaped and has dimensions which correspond with the wedge-shaped areas 33 on the carousel.

In the embodiment illustrated in Fig. 5, the reagent pack contains three vials 53 of reagent. As known to those skilled in the art, the three vial arrangement is best suited for use in assays of the type requiring a pre-treatment reagent, usually to bind the analyte of interest from certain proteins in a sample, an analyte complement for binding the unbound analyte, and a specifically tagged or labeled tracer reagent for indicating the presence of the analyte of interest. In the embodiment illustrated, each of the required reagents for this type of assay is contained in one of the vials 53 of a reagent pack.

In other embodiments, a reagent pack containing a different number of vials may be desired. For example, in certain assays which are particularly sensitive to carryover of any reagent, a fourth vial is advantageously provided to contain a wash or buffer reagent that can be used to rinse the pipette heading means used for transferring reagents after it accesses the reagent. It should be understood, therefore, that it is not intended to limit the invention to a three vial reagent pack and that reagent packs containing various vial arrangements (several are schematically illustrated in Fig. 1) may be utilized.

Preferably, also, the vials are provided with suitable means (not shown) for sealing the openings in the vials when a reagent pack is not in use. The sealing means can comprise threaded covers or other suitable sealing structure which does not form a part of the present invention. Although it is possible to make the vials integral with the housing, if desired, it is generally preferable that the vials be separate components as it is usually easier to fill the small vials separately; and, because of their close proximity in the housing, there would be a substantial risk of spilling the contents of one vial into an adjacent vial during the filling process, thus contaminating the reagents therein.

Figs. 6-8 illustrate specific details of reagent pack housing 51. As best illustrated in Fig. 6, the inner surface 70 of the housing (i.e., the surface that will face inwardly when the reagent pack is mounted in carousel 21) comprises a flat, narrow surface having a pair of parallel vertical slots 72 extending upwardly from the bottom to define a downwardly extending arm 73 therebetween. The arm 73 is also formed to have a small tab 74 extending outwardly from the bottom end thereof. Arm 73 functions as a flexible, spring member which is capable of being deflected inwardly during mounting and release of the reagent pack from the carousel, and the tab 74 is adapted to be received within an aligned slot 38 in the carousel to help retain the reagent pack on the carousel.

The outer surface of the housing comprises a curved surface 76 (see also Fig. 5) , the bottom edge of which is recessed slightly across the width thereof to define a recess 77 extending across the bottom of the outer surface of the housing. A small outwardly extending tab 78 is provided on each side of the recess

77 and the tabs 78 are adapted to be received within aligned slots 42 on the carousel to further assist in retaining the reagent pack on the carousel.

To mount a reagent pack 22 onto the carousel 21, it is only necessary to position the pack in one of the wedge-shaped areas 33 on the base of the carousel with the tab 74 thereof inserted into the slot 38 associated with the area. The pack is then pushed slightly toward the center of the carousel against the spring force of the flexible arm 73 until the recess 77 and the tabs 78 clear the annular rim 41 on the carousel. Then, the outer end of the pack is pushed down against the base of the carousel and released. Upon being released, the reagent pack will be pushed outwardly from the center of the carousel by the flexible arm 73 causing the two tabs 78 on the outer surface of the pack to enter into the aligned slots 42 to secure the pack in place on.the carousel.

To remove the pack from the carousel, it is only necessary to apply a slight force to the pack to push it toward the center of the carousel against the force of arm 73 until the tabs 78 clear the slots 42, and then raise the outer end of the pack upwardly slightly above the rim, and the entire pack will be immediately released.

With the present invention, therefore, individual reagent packs can be very quickly and easily inserted into and removed from the carousel at any wedge-shaped area thereon and will be firmly and reliably retained on the carousel independent of the presence or location of any other reagent packs on the carousel. Therefore, the carousel can reliably support any number of reagent packs from one to a full complement depending on the number and types of tests to be performed during a particular run of the analyzer.

In addition, the various tabs and associated interlocking mounting structure of the reagent pack housing are preferably molded integrally with the housing to provide a low-cost structure that can be easily mass-produced and is readily disposable w__en the reagents carried therein are exhausted.

The flexibility of arm 73 can be controlled by controlling the length of the slots 72 and their thickness to provide a reagent pack that can be easily

Claims

12 inserted on and removed from the carousel and yet is reliably retained therein.The curved outer surface 76 of the reagent.pack is designed to carry identification means thereon capable of being automatically read in the analyzer to identify the pack. The information may conveniently be on a label affixed to the surface, and comprise, for example, the name of the particular assay with which the reagent pack is to be used in a machine-readable form such as a bar code 83 as to permit the label to be read by the identification means reading means 25 in the analyzer.The provision of the machine-readable identification means on the reaction pack permits the carousel to function as a random access carousel such that reagent packs can be randomly mounted on the carousel at any position.In particular, prior to performing a desired test or a series of tests, the appropriate reagent pack or packs for the tests are mounted in the carousel randomly on any desired area 33 thereon. The carousel is then mounted in the analyzer and caused to rotate stepwise from position to position for a full revolution. During the rotation, the bar codes 83 on each of the reagent packs are read by the reading means 25 to identify each reagent pack on the carousel and its position on the carousel. The information is stored in the control means 50 of the analyzer and, thereafter, the analyzer is able to operate to automatically position the appropriate reagent pack at the preparation station along with the proper sample container on the sample carousel to permit the desired assay to be carried out.According to the present invention, therefore, the operator does not have to mount the reagent pack at any particular position on the reagent carousel nor does he have to manually program the position of each reagent pack into the analyzer. The operator can simply insert the selected reagent packs at any position on the carousel. This results in a significant saving of .time and substantially eliminates the risk of operator error in improperly positioning a reagent pack or in mounting an incorrect reagent pack in the carousel.While what has been described constitutes a presently preferred embodiment, it should be understood that the invention could take numerous other forms which do not depart from the spirit and scope of the invention. Accordingly, it should be understood that the invention should be limited only insofar as is required by the scope of the following claims. We claim:

1. A reagent handling system for automated . clinical analyzer apparatus comprising: a plurality of reagent containment means, each carrying one or more reagents for performing a particular assay on a sample in said apparatus; arid a support means for supporting one or a plurality of said reagent containment means in said analyzer, said support means having a plurality of support positions for supporting said reagent containment means, wherein each of said plurality of reagent containment means includes identification means thereon for permitting automatic identification of each reagent containment means, whereby any selected one of said plurality of reagent containment means may be randomly positioned at any one of said support positions on said support means, and be automatically identified by said identification means to enable said particular assay to be automatically performed on said sample with the one or more reagents in said selected reagent containment means.

2. The reagent handling system of claim 1 wherein said support means comprises a rotatable carousel.

3. The reagent handling system of claim 2 wherein said plurality of reagent containment means support positions comprise a plurality of wedge-shaped support areas positioned around the circumference of the carousel, and wherein each of said reagent containment means comprises a unitary wedge-shaped reagent pack.

4. The reagent handling system of claim 3 wherein said identification means comprises machine-readable indicia on a surface of each of said reagent packs.

5. The reagent handling system of claim 1 wherein said identification means comprises machine-readable identification means.

6. The reagent handling system of claim 5 wherein said machine-readable identification means comprises bar code means.

7. The reagent handling system of claim 5 wherein said support means includes means for moving said support means to position each reagent containment means supported thereon adjacent a reading means in said analyzer apparatus for automatically identifying each of the reagent containment means supported thereon.

8. The reagent handling system of claim 1 and further including interlocking means on said support means and on each of said reagent containment means for releasably mounting each of said reagent containment means at any one of said support positions.

9. The reagent handling system of claim 8 wherein each of said reagent containment means comprises a housing carrying a plurality of reagent-containing vials therein, and wherein said interlocking means comprises an arrangement of cooperating interlocking tabs and slots on said housing and said support means.

10. The reagent handling system of claim 9 wherein said housing includes a flexible arm integral therewith for releasably interlocking said arrangement of tabs and slots.

11. Automated clinical analyzer apparatus for conducting assays of fluid samples for substances contained therein comprising: sample support means for supporting a plurality of fluid samples to be tested; reagent support means for supporting a plurality of reagent containment means containing reagents to be combined with said samples at a preparation station to provide a reaction mixture, said reagent support means including a plurality of support positions for supporting a plurality of reagent containment means; and means for analyzing said reaction mixture, the improvement comprising wherein each of said reagent containment means includes machine-readable identification means thereon for permitting automatic identification of each reagent containment means, and wherein said apparatus further includes means for reading said machine-readable identification means for identifying each reaction containment means and its position on said reagent support means whereby any of said plurality of said reagent containment means may be randomly positioned at any of said support positions on said reagent support means.

12. The apparatus of claim 11 wherein said machine-readable identification means comprises bar code means.

13. The apparatus of claim 11 wherein said reagent support means comprises a carousel which is rotatable relative to said reading means to permit the machine-readable identification on each of said reagent containment means to be read by said reading means.

14. A reagent pack containing one or more reagents for performing a particular assay on a fluid sample in an automated clinical analyzer apparatus, said reagent pack being adapted to be supported on a reagent pack support means mountable in said analyzer and having a plurality of reagent pack support positions, said reagent pack comprising: machine-readable identification means thereon for permitting automatic identification of said reagent pack in said analyzer, and means for releasably mounting said reagent pack at any one of said plurality of support positions on said support means, whereby said reagent pack may be randomly mounted at any one of said support positions and be automatically identified by said identification means thereon to permit said particular assay to be performed on said sample.

15. The reagent pack of claim 14 wherein said machine-readable identification means comprises bar code means.

16. The reagent pack of claim 14 wherein said reagent pack comprises a housing supporting a plurality of reagent-containing vials, and wherein said machine-readable identification means is on a surface of said housing.

17. The reagent pack of claim 16 wherein said housing comprises wedge-shaped housing and includes a curved side surface, and wherein said machine-readable identification means is on said curved surface.

18. The reagent pack of claim 16 wherein said releasable mounting means comprises interlocking means on said housing for cooperating with complementary interlocking means at each of said plurality of support positions on said support means.