Biosensor membranes composed of polymers containing heterocyclic nitrogens
Novel membranes comprising various polymers containing heterocyclic nitrogen groups are described. These membranes are usefully employed in electrochemical sensors, such as amperometric biosensors. More particularly, these membranes effectively regulate a flux of analyte to a measurement electrode in an electrochemical sensor, thereby improving the functioning of the electrochemical sensor over a significant range of analyte concentrations. Electrochemical sensors equipped wish such membranes are also described.
1. A membrane for use in an analytical sensor, comprising:
a polymer having the formula:
wherein the solid horizontal line represents a polymer backbone;
A is an alkyl substituted with a water-soluble constituent;
D is selected from phenylalkyl, alkoxystyrene, hydroxyalkyl, alkoxyalkyl, alkoxycarbonylalkyl, a poly(ethylene glycol)-containing constituent, and a polyhydroxyl-containing constituent; and
each of n, l, p and q is independently a positive number.
2. The membrane of claim 1 , wherein A is negatively charged.
3. The membrane of claim 1 , wherein A is an alkyl substituted sulfonate, alkyl substituted carboxylate, or alkyl substituted phosphate.
4. The membrane of claim 1 , wherein A is sulfopropyl, sulfobutyl, carboxypropyl, or carboxypentyl.
5. The membrane of claim 1 , wherein A is of the formula L−G, where L is a C2-C12 linear or branched alkyl linker and G is a negatively charged carboxy or sulfonate.
6. The membrane of claim 5 , wherein L is substituted with an aryl, alkoxy, alkenyl, alkynyl, —F, —Cl, —OH, aldehyde, ketone, ester, or amide.
7. The membrane of claim 1 , wherein D is styrene or C1-C18 alkyl methacrylate.
8. The membrane of claim 1 , wherein an average molecular weight of the polymer is above about 50,000.
9. The membrane of claim 1 , wherein an average molecular weight of the polymer is above about 50,000 to about 200,000.
10. The membrane of claim 1 , wherein the polymer further comprises a B-containing copolymer such that the polymer has the formula:
wherein B is a modifier and m is a positive number.
11. The membrane of claim 10 , wherein B is selected from a chelator, a negatively charged constituent, a hydrophobic hydrocarbon constituent, a hydrophilic hydroxyl or polyhydroxy constituent, a silicon polymer, and a poly(ethylene glycol).
12. The membrane of claim 10 , wherein B is a poly(ethylene glycol) having a molecular weight of from about 100 to about 20,000.
13. The membrane of claim 10 , wherein B is a poly(ethylene glycol) having a molecular weight of from about 200 to about 2000.
14. The membrane of claim 10 , wherein [n/(n+m+l+p)]×100% is from about 1% to about 25%.
15. The membrane of claim 10 , wherein [m/(n+m+l+p)]×100% is from about 1% to about 15%.
16. The membrane of claim 10 , wherein [l/(n+m+l+p)]×100% is from about 20% to about 90%.
17. The membrane of claim 10 , wherein [p/(n+m+l+p)]×100% is from about 1% to about 50%.
18. The membrane of claim 1 , wherein at least one heterocyclic nitrogen constituent of the polymer is independently selected from pyridine, imidazole, oxazole, thiazole, pyrazole, and any derivative thereof.
19. The membrane of claim 1 sufficient to limit a flux of glucose or lactate thereacross.
20. The membrane of claim 1 sufficient to limit a flux of glucose or lactate thereacross in vivo.
21. An electrochemical sensor, comprising:
a working electrode comprising:
a sensing layer in contact with a conductive material of the electrode; a membrane disposed over the sensing layer, the membrane comprising a polymer having the formula:
wherein the solid horizontal line represents a polymer backbone;
A is an alkyl substituted with a water-soluble constituent;
D is selected from phenylalkyl, alkoxystyrene, hydroxyalkyl, alkoxyalkyl, alkoxycarbonylalkyl, a poly(ethylene glycol)-containing constituent, and a polyhydroxyl-containing constituent; and
each of n, l, p and q is independently a positive number; and
a counter electrode in electrochemical communication with the working electrode.
22. An electrochemical sensor, comprising:
a working electrode comprising:
a sensing layer in contact with a conductive material of the electrode;
a membrane disposed over the sensing layer, the membrane comprising a crosslinker and a polymer having the formula:
wherein the solid horizontal line represents a polymer backbone;
A is an alkyl substituted sulfonate, alkyl substituted carboxylate or alkyl substituted phosphate;
n is a positive number; and
a counter electrode in electrochemical communication with the working electrode.
23. The electrochemical sensor of claim 22 , wherein A is negatively charged.
24. The electrochemical sensor of claim 22 , wherein A is sulfopropyl, sulfobutyl, carboxypropyl, or carboxypentyl.
25. The electrochemical sensor of claim 22 , wherein A is of the formula L−G, where L is a C2-C12 linear or branched alkyl linker and G is a negatively charged carboxy or sulfonate.
26. The electrochemical sensor of claim 22 , wherein the polymer has a formula selected from a group consisting of:
wherein each of n, l, p and q is independently a positive number.
27. The electrochemical sensor of claim 22 , wherein the molecular weight of the polymer is between about 50,000 and 1,000,000 kD.
28. A membrane for use in an electrochemical sensor, comprising:
a crosslinker; and
a polymer having the formula:
wherein the solid horizontal line represents a polymer backbone;
A is an alkyl substituted sulfonate, alkyl substituted carboxylate or alkyl substituted phosphate;
n is a positive number.
29. The membrane of claim 28 , wherein A is negatively charged.
30. The membrane of claim 28 , wherein A is sulfopropyl, sulfobutyl, carboxypropyl, or carboxypentyl.
31. The membrane of claim 28 , wherein A is of the formula L−G, where L is a C2C12 linear or branched alkyl linker and G is a negatively charged carboxy or sulfonate.
32. The membrane of claim 28 , wherein the polymer has a formula selected from the group consisting of:
wherein each of n, l, p and q is independently a positive number.
33. The membrane of claim 28 , wherein the polymer has a molecular weight of between about 50,000-1,000,000 kD.