Sintered polymer membrane for analyte detection device

1. An analyte detection device for detecting an analyte in a liquid sample, comprising a sample application pad in communication with an analyte immobilization membrane, the analyte immobilization membrane comprising a multi-layer coated material comprising a sintered, porous, polymeric substrate, a first layer and a second layer, the first layer comprising molecules of polyethylenimine bound to a surface of the polymeric substrate at solution conditions for forming covalent bonds and electrostatic interactions and the second layer comprising molecules of poly(acrylic acid), a copolymer containing poly(acrylic acid), or a surfactant bound to the first layer through covalent bonds, electrostatic interactions, or combinations thereof.

2. The analyte detection device of claim 1 , wherein the substrate comprises a polyolefin, polyester, polyurethane, polycarbonate, polyetheretherketone, poly(phenylene oxide), poly(ether sulfone), or nylon.

3. The analyte detection device of claim 2 , wherein the polyolefin is comprises ethylene vinyl acetate, ethylene methyl acetate, polyethylene, polypropylene, ethylene-propylene rubber, ethylene-propylene-diene rubbers, poly(1-butene), polystyrene, poly(2-butene), poly(1-pentene), poly(2-pentene), poly(3-methyl-1-pentene), poly(4-methyl-1-pentene), 1,2-poly-1,3butadiene, 1,4-poly-1,3-butadiene, polyisoprene, polychloroprene, poly(vinyl acetate), poly(vinylidene chloride), poly(vinylidene fluoride), poly(tetrafluoroethylene), or a mixture thereof.

4. The analyte detection device of claim 1 , wherein the substrate further comprises a solid wetting agent.

5. The analyte detection device of claim 1 , wherein the substrate has been treated with an aqueous or organic solution of one or more wetting agents.

6. The analyte detection device of claim 1 , wherein the second layer comprises a fluorinated surfactant.

7. The analyte detection device of claim 1 , wherein the multi-layer coated material further comprises one or more additional layers, wherein each additional layer is bound to the layer below it through covalent bonds, electrostatic interactions, or combinations thereof.

8. The analyte detection device of claim 7 , wherein the first layer comprises molecules of polyethylenimine; the second layer comprises molecules of poly(acrylic acid); and the one additional layer comprises molecules of polyethylenimine, polyvinylamine, or a surfactant.

9. The analyte detection device of claim 1 , wherein the device comprises a lateral flow device, a flow-through device, or a dipstick device.

10. The analyte detection device of claim 1 , wherein the liquid sample comprises a body fluid of a mammal.

11. The analyte detection device of claim 10 , wherein the body fluid comprises blood, urine, or saliva.

12. An analyte detection device for detecting an analyte in a liquid sample comprising a sample application pad in communication with an analyte immobilization membrane, the analyte immobilization membrane comprising a multi-layer coated material comprising a sintered, porous, polymeric substrate, a first layer and a second layer, the first layer comprising molecules of polyallylammonium chloride bound to a surface of the polymeric substrate at solution conditions for forming covalent bonds and electrostatic interactions; and the second layer comprising molecules of polyvinylsulfate bound to the first layer through covalent bonds, electrostatic interactions, or combinations thereof.

13. The analyte detection device of claim 1 , wherein the polymeric substrate has been surface activated.

14. The analyte detection device of claim 1 , wherein the polymeric substrate comprises ethylene vinyl acetate, ethylene methyl acrylate, low density polyethylene, linear low density polyethylene, high density polyethylene, ultra-high molecular weight polyethylene, ethylene-propylene rubbers, ethylene-propylene-diene rubbers, polystyrene, poly(1-butene), poly(2-butene), poly(1-pentene), poly(2-pentene), poly(3-methyl-1-pentene), poly(4-methyl-1-pentene), 1,2-poly-1,3-butadiene, 1,4-poly-1,3-butadiene, polyisoprene, polychloroprene, poly(vinyl acetate), poly(vinylidene chloride), poly(vinylidene fluoride), poly(tetrafluoroethylene), or combinations thereof.

15. An analyte detection device comprising a sample application pad in communication with an analyte immobilization membrane, the analyte immobilization membrane comprising a multi-layer coated material comprising a substrate, a first layer, and a second layer wherein:

the substrate comprises a sintered porous polymeric material;

the first layer comprises polyelectrolyte molecules bound to a surface of the substrate at solution conditions for forming covalent bonds and electrostatic interactions; and

the second layer comprises polyelectrolyte molecules bound to the first layer through covalent bonds, electrostatic interactions, or combinations thereof,

wherein the polyelectrolyte molecules in the first layer and the second layer are independently selected from the group consisting of polyethylenimine, quaternized polyacrylamide, polyvinylamine, polyallylamine, chitosan, poly(acrylate trialkyl ammonia salt ester), cellulose, poly(acrylic acid), polymethylacrylic acid, polyvinylsulfate, poly(styrenesulfonic acid), poly(vinylsulfonic acid), poly(toluene sulfonic acid), heparin, alginic acid, dextran sulfate, adipic acid, poly(methyl vinyl ether-alt-maleic acid, polyallylammonium chloride, and a salt and a copolymer thereof.

16. The analyte detection device of claim 1 , wherein the analyte immobilization membrane has a thickness ranging from about 1 μm to about 1 mm.

17. The analyte detection device of claim 1 , wherein the analyte immobilization membrane has a thickness ranging from about 10 μm to about 500 μm.

18. The analyte detection device of claim 1 , wherein the analyte immobilization membrane further comprises a test region and a control region.

19. A method of detecting an analyte comprising:

providing a analyte detection device comprising a sample application pad in communication with a conjugate release pad, the conjugate release pad in communication with an analyte immobilization membrane, wherein the analyte immobilization membrane comprises a multi-layer coated material comprising a sintered, porous, polymeric substrate, a first layer and a second layer, the first layer comprising molecules of polyethylenimine bound to a surface of the polymeric substrate at solution conditions for forming covalent bonds and electrostatic interactions; and the second layer comprising molecules of poly(acrylic acid), a copolymer containing poly(acrylic acid), or a surfactant bound to the first layer through covalent bonds, electrostatic interactions, or combinations thereof;

applying a liquid comprising an analyte to the sample application pad;

transferring the liquid to the conjugate release pad;

binding the analyte to a reagent to produce a complex;

transferring the complex from the conjugate release pad to the analyte immobilization membrane; and

binding the complex on the analyte immobilization membrane.

20. The method of claim 19 , further comprising detecting the analyte bound on the analyte immobilization membrane.

21. The analyte detection device of claim 1 , wherein leaching of polyethylenimine from the analyte immobilization membrane ranges from about 0.15 percent to about 2 percent of the total amount of polyethylenimine bound to the porous substrate.

22. The analyte detection device of claim 1 , wherein the analyte immobilization membrane is dry.

23. The analyte detection device of claim 1 , wherein the sintered porous polymeric substrate has an average pore size ranging from about 0.1 μm to about 200 μm.

24. The analyte detection device of claim 1 , wherein the sintered porous polymeric substrate has an average pore size ranging from about 1 μm to about 50 μm.

25. An analyte detection device comprising a porous strip, the porous strip comprising a sample receiving zone and an analyte immobilization zone dowstream from the sample receiving zone, wherein the analyte immobilization zone comprises a multi-layered coated material comprising a porous polymeric substrate, a first layer, and a second layer, the first layer comprising molecules of polyethylenimine bound to a surface of the substrate at solution conditions for forming covalent bonds and electrostatic interactions, and the second layer comprising molecules of poly(acrylic acid), a copolymer containing poly(acrylic acid), or a surfactant bound to the first layer through covalent bonds, electrostatic interactions, or combinations thereof.

26. An analyte detection device comprising a sample application pad coupled to a conjugate release pad, the conjugate release pad coupled to an analyte detection membrane, wherein the analyte detection membrane comprises a multi-layered coated material comprising a porous polymeric substrate, a first layer, and a second layer, the first layer comprising molecules of polyethylenimine bound to a surface of the substrate at solution conditions for forming covalent bonds and electrostatic interactions, and the second layer comprising molecules of poly(acrylic acid), a copolymer containing poly(acrylic acid), or a surfactant bound to the first layer through covalent bonds, electrostatic interactions, or combinations thereof.

27. An analyte detection device for detecting an analyte in a liquid sample, comprising a sample applicator pad in communication with an analyte immobilization membrane, the analyte immobilization membrane comprising a multi-layer coated material comprising a sintered, porous, polymeric substrate, a first layer and a second layer, the first layer comprising molecules of polyethylenimine bound to a surface of the polymeric substrate at solution conditions for forming covalent bonds and electrostatic interactions and the second layer comprising molecules of poly(acrylic acid), a copolymer containing poly(acrylic acid), or a surfactant bound to the first layer through covalent bonds, electrostatic interactions, or combinations thereof, wherein the analyte immobilization membrane has a wicking rate of at least 30 seconds/4 cm.