MEMBRANES AND METHODS FOR COATING MEMBRANES

• US 20070274861A1
• Filed: 06/06/2007
• Published: 11/29/2007
• Est. Priority Date: 12/07/2004
• Status: Active Grant

• Current Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Fischer, Thomas, Mangold, Dieter, Klepp, Juergen, Schaeffler, Juergen, Lerch, Rolf
• Granted Patent: US 7,955,563 B2
• Time in Patent Office: Days
• US Class Current: 422/56
• CPC Class Codes: B01D 67/0088 Physical treatment with compounds, e.g. swelling, coating or impregnation
• CPC Class Codes: B01D 69/106 Membranes in the pores of a support, e.g. polymerized in the pores or voids
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: G01N 33/521 Single-layer analytical elements
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A method for applying reactive films containing solids to microporous membranes is provided wherein the membrane is firstly moistened and the reactive film containing solids is applied to the membrane while it is still moist. Membranes produced in this manner can contain reactive films having a high proportion of film openers and can be used advantageously in diagnostic elements for detecting constituents and, in particular, large hydrophobic analytes in body fluid.

Claims

1. A method for applying reactive films containing solids to microporous, absorbent, blood-separating membranes comprising:

providing a microporous membrane;

moistening the microporous membrane with water or an aqueous solution; and

applying a reactive film containing solids to the microporous membrane which said membrane is still moist.

2. The method according to claim 1, wherein the membrane is configured to separate plasma or serum from whole blood.

3. The method according to claim 1, wherein the reactive film further contains film formers and film openers, wherein said film openers are inorganic or organic particulate fillers.

4. The method according to claim 1, wherein the reactive film further contains optically blocking pigments, wetting agents, swelling agents, and combinations thereof.

5. The method according to claim 1, wherein the reactive film containing solids is water-resistant and/or water-insoluble.

6. The method according to claim 1, wherein the reactive film further contains at least portions of a detection reagent for an analyte.

7. The method according to claim 6, wherein the detection reagent is provided in a hydrophobic matrix of film formers.

8. The method according to claim 3, wherein the amount of filler is greater than the amount of film former.

9. The method according to claim 3, wherein the film opener to film former mass ratio is about 10:

1 to about 1;

1.

10. The method according to claim 3, wherein the film opener to film former mass ratio is about 5:

1 to 2;

1.

11. The method according to claim 1 further comprising applying the reactive film to the membrane directly after moistening.

12. The method according to claim 1 further comprising moistening the membrane by bath impregnation, slotted nozzle impregnation, spraying, or combinations thereof.

13. The method according to claim 1, wherein the water or the aqueous solution contains a surfactant.

14. The method according to claim 1 further comprising applying tithe reactive film by knife coating, roller application, slot die coating, or combinations thereof.

15. A microporous, absorbent, blood-separating membrane formed by the method according to claim 1.

16. A microporous, absorbent blood-separating membrane comprising a reactive film containing solids coated on a substrate, wherein the reactive film containing solids is a water-resistant, water-insoluble film which contains all or at least portions of a detection reagent for an analyte to be detected in a hydrophobic matrix of film formers and which contains inorganic or organic particulate fillers as film openers, characterized in that the mass ratio of film opener to film former is about 10:

1 to about 1;

1.

17. The membrane according to claim 16, wherein the mass ratio of film opener to film former is about 5:

1 to about 2;

1.

18. The membrane according to claim 16, wherein the membrane is configured to separate plasma or serum from whole blood.

19. The membrane according to claim 16, wherein the reactive film further contains optically blocking pigments, wetting agents, swelling agents, and combinations thereof.

20. A diagnostic element for detecting constituents of body fluids containing a membrane coated with a reactive film according to claim 16.