Adhered membranes retaining porosity and biological activity

• US 20040235182A1
• Filed: 04/01/2004
• Published: 11/25/2004
• Est. Priority Date: 04/02/2003
• Status: Active Grant

• Current Assignee: Alere San Diego Incorporated (Abbott Laboratories)
• Original Assignee: Cholestech Corporation (Abbott Laboratories)
• Inventors: Jones, Ronald M.
• Granted Patent: US 7,195,921 B2
• Time in Patent Office: Days
• US Class Current: 436/71
• CPC Class Codes: G01N 2800/044 Hyperlipemia or hypolipemia, e.g. dyslipidaemia, obesity
• CPC Class Codes: G01N 33/543 with an insoluble carrier for immobilising immunochemicals
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: G01N 33/54393 Improving reaction conditions or stability, e.g. by coating or irradiation of surface, by reduction of non-specific binding, by promotion of specific binding
• CPC Class Codes: G01N 33/92 involving lipids, e.g. cholesterol , lipoproteins, or their receptors steroid hormones G01N33/743

Abstract

An assay pad for measuring the concentration of HDL-associated cholesterol in a sample, a method for using the pad, and a diagnostic assay device for carrying out the method are described. The assay pad includes a polymer adhesive or heat laminate bond. The assay design prevents interference by reagents used for such removal with the HDL quantification reaction or with other assays carried out on the same sample. If desired, removal of non-HDL lipoproteins and assay of HDL cholesterol can be carried out without interruption of the assay.

Claims

1. An assay device for measuring serum cholesterol associated with high-density lipoproteins (HDL) in a blood fluid sample containing lipoproteins other than HDLs, the device comprising:

a sample distribution array;

a HDL test pad in which HDL concentration can be assayed; and

a reagent pad containing a binding reagent effective to selectively bind and remove non-HDLs from the fluid sample;

wherein said HDL test pad and said reagent pad are joined.

2. The device of claim 1, wherein said HDL test pad and said reagent pad are joined by a heat formed bond.

3. The device of claim 1, wherein said HDL test pad and said reagent pad are joined by an acrylic acid copolymer adhesive bond.

4. The device of claim 3, wherein said acrylic acid copolymer is ethylene acrylic acid copolymer.

5. The device of claim 1, wherein at least one of said HDL test pad or said reagent pad is composed of a polysulfone layer.

6. The device of claim 1, further comprising a sieving pad effective to remove cellular components from the blood fluid sample prior to the sample contacting said sample distribution array.

7. The device of claim 1, further comprising a cassette body for containing said sieving pad, said cassette body comprising a well for containing said blood fluid sample and in fluid communication with said sieving pad.

8. The device of claim 7, further comprising a reaction bar comprising mounting means effective to attach said reaction bar to said cassette body.

9. The device of claim 1, wherein said reagent comprises a binding polyanionic reagent.

10. The device of claim 9, wherein said binding polyanionic reagent includes a sulfonated polysaccharide.

11. The device of claim 1, wherein said HDL test pad contains reagents which produce a detectable change in the presence of HDL cholesterol.

12. The device of claim 11, wherein said change can be detected optically.

13. The device of claim 1, wherein said HDL test pad comprises a biosensor.

14. The device of claim 13, wherein said biosensor is effective to electrochemically measure production of oxygen or hydrogen peroxide.

15. A method of preparing a device suitable for measuring serum cholesterol comprising:

providing a reagent pad and an HDL test pad formed of an asymmetric polysulfone membrane having a small pore side and an open pore side;

orienting the reagent pad with the HDL test pad such that the small pore side of the reagent pad contacts the open pore side of the HDL test pad;

heating to adhere said HDL test pad and said reagent pad; and

applying (i) HDL test reagents to said HDL test pad, and (ii) a reagent effective to selectively bind and remove non-HDLs from a fluid sample to said reagent pad to form said device.

16. The method of claim 15, wherein said heating is at a temperature above 165°

C.

17. A method of preparing a device suitable for measuring serum cholesterol comprising:

coating a reagent pad with an acrylic acid copolymer;

applying (i) HDL test reagents to said HDL test pad, and (ii) a reagent effective to selectively bind and remove non-HDLs from a fluid sample to said reagent pad;

heating to adhere said HDL test pad and said reagent pad to form said device.

18. The method of claim 17, wherein said acrylic acid copolymer is ethylene acrylic acid copolymer.

19. The method of claim 18, wherein the ethylene acrylic acid copolymer is about 4.0% to about 10.0% emulsion.

20. The method of claim 17, further comprising the step of drying said reagent pad after said coating step.

21. The method of claim 17, wherein each of said HDL test pad and reagent pad have a small pore side and an open pore side;

further comprising the step of orienting the HDL test pad and the reagent pad such that the small pore side of the reagent pad faces the open pore side of the HDL test pad.

22. The method of claim 17, wherein said heating step comprises applying a temperature of between 75°

and 90°

C.

23. A method of measuring serum cholesterol associated with high-density lipoproteins (HDL) in a blood fluid sample containing lipoproteins other than HDLs, comprising:

contacting the sample with a laminate comprising (i) an HDL test pad having a detectable indicator of HDL cholesterol, (ii) a reagent pad containing a reagent effective to selectively bind and remove non-HDLs from the fluid sample;

wherein said blood fluid sample passes through said laminate by capillary action and/or gravity through said laminate to permit measurement of HDL concentration.

24. The method of claim 23, wherein contact between said sieving pad and said sample distribution pad is broken when a desired amount of sample has been transferred.

25. The method of claim 23, wherein said reagent comprises a sulfonated polysaccharide.

26. The method of claim 23, wherein at least one of said HDL test pad or said reagent pad comprises a porous polymeric membrane.

27. The method of claim 23, wherein said reagent pad comprises multiple stacked layers, at least one of which contains a reagent effective to bind non-HDLs.

28. The method of claim 23, wherein said measurement of HDL concentration is via optical detection.

29. The method of claim 23, wherein said HDL test pad comprises a biosensor.

30. The method of claim 29, wherein said biosensor is effective to electrochemically measure production of oxygen or hydrogen peroxide.