DIRECT ELECTRON TRANSFER USING ENZYMES IN BIOANODES, BIOCATHODES, AND BIOFUEL CELLS

• US 20110014549A9
• Filed: 11/02/2006
• Published: 01/20/2011
• Est. Priority Date: 11/02/2005
• Status: Active Grant

• Current Assignee: St. Louis University
• Original Assignee: St. Louis University
• Inventors: Treu, Becky L., Duma, Rodica, Minteer, Shelley D.
• Granted Patent: US 8,415,059 B2
• Time in Patent Office: Days
• US Class Current: 429/523
• CPC Class Codes: C12N 11/04 entrapped within the carrier, e.g. gel or hollow fibres
• CPC Class Codes: C12N 11/082 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C12N 11/089 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C12N 11/14 Enzymes or microbial cells immobilised on or in an inorganic carrier
• CPC Class Codes: H01M 4/90 Selection of catalytic material
• CPC Class Codes: H01M 8/16 Biochemical fuel cells, i.e. cells in which microorganisms function as catalysts
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

Bioanodes, biocathodes, and biofuel cells comprising an electron conductor, at least one anode enzyme or cathode enzyme, and an enzyme immobilization material. The anode enzyme is capable of reacting with a fuel fluid to produce an oxidized form of the fuel fluid, and capable of releasing electrons to the electron conductor. The cathode enzyme is capable of reacting with an oxidant to produce water, and capable of gaining electrons from the electron conductor. The enzyme immobilization material for both the anode enzyme and the cathode enzyme is capable of immobilizing and stabilizing the enzyme, and is permeable to the fuel fluid and/or the oxidant.

Claims

1-38. -38. (canceled)

39. A bioanode comprising

(a) an electron conductor;

(b) at least one anode enzyme capable of reacting with a fuel fluid to produce an oxidized form of the fuel fluid, the anode enzyme being capable of releasing electrons to the electron conductor; and

(c) an enzyme immobilization material capable of immobilizing and stabilizing the enzyme, the material being permeable to the fuel fluid.

40. The bioanode of claim 39 wherein the enzyme immobilization material comprises a micellar or inverted micellar structure.

41. The bioanode of claim 39 wherein the enzyme immobilization material comprises either

(a) a modified perfluoro sulfonic acid-PTFE copolymer or a hydrophobically modified alginate wherein the enzyme immobilization material is modified with a hydrophobic cation larger than NH₄⁺;

or

(b) a hydrophobically modified polysaccharide.

42. The bioanode of claim 41 wherein the hydrophobic cation comprises a quaternary ammonium ion represented by Formula 4

43. The bioanode of claim 39 wherein said hydrophobically modified polysaccharide corresponds to Formula 1

44. The bioanode of claim 43 wherein R₁₀ is independently hydrogen or alkyl and R₁₁ is independently hydrogen or alkyl.

45. The bioanode of claim 39 wherein the electron conductor comprises carbon cloth, carbon paper, carbon screen printed electrodes, carbon black, carbon powder, carbon fiber, single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, carbon nanotube arrays, diamond-coated conductors, glass carbon, mesoporous carbon, graphite, uncompressed graphite worms, delaminated purified flake graphite, high performance graphite, highly ordered pyrolytic graphite, pyrolytic graphite or polycrystalline graphite.

46. The bioanode of claim 39 wherein the anode enzyme comprises a PQQ-dependent dehydrogenase or a lipoxygenase.

55. A biofuel cell for generating electricity comprising:

a fuel fluid;

a bioanode of claim 39; and

a cathode.

59. The biofuel cell of claim 55 wherein the fuel fluid comprises ammonia, methanol, ethanol, propanol, isobutanol, butanol, isopropanol, an allyl alcohol, an aryl alcohol, glycerol, propanediol, mannitol, glucuronate, aldehyde, a carbohydrate, glucose, glucose-1, D-glucose, L-glucose, glucose-6-phosphate, lactate, lactate-6-phosphate, D-lactate, L-lactate, fructose, galactose-1, galactose, aldose, sorbose, mannose, glycerate, coenzyme A, acetyl Co-A, malate, isocitrate, formaldehyde, acetaldehyde, acetate, citrate, L-gluconate, beta-hydroxysteroid, alpha-hydroxysteroid, lactaldehyde, testosterone, gluconate, a fatty acid, a lipid, phosphoglycerate, retinal, estradiol, cyclopentanol, hexadecanol, a long-chain alcohol, coniferyl-alcohol, cinnamyl-alcohol, formate, a long-chain aldehyde, pyruvate, butanal, acyl-CoA, a steroid, an amino acid, flavin, NADH, NADH₂, NADPH, NADPH₂ or hydrogen.

47. A biocathode comprising:

(a) an electron conductor;

(b) at least one cathode enzyme capable of reacting with an oxidant to produce water, the cathode enzyme being capable of gaining electrons from the electron conductor; and

(c) an enzyme immobilization material capable of immobilizing and stabilizing the enzyme, the material being permeable to the oxidant.

48. The biocathode of claim 47 wherein the enzyme immobilization material comprises a micellar or inverted micellar structure.

49. The biocathode of claims 47 wherein the enzyme immobilization material comprises either

(a) a modified perfluoro sulfonic acid-PTFE copolymer or a hydrophobically modified alginate wherein the enzyme immobilization material is modified with a hydrophobic cation larger than NH₄⁺;

or

(b) a hydrophobically modified polysaccharide.

50. The biocathode of claim 49 wherein the hydrophobic cation comprises a quaternary ammonium ion represented by Formula 4

51. The biocathode of claim 49 wherein said hydrophobically modified polysaccharide corresponds to Formula 1

52. The biocathode of claim 51 wherein R₁₀ is independently hydrogen or alkyl and R₁₁ is independently hydrogen or alkyl.

53. The biocathode of claim 47 wherein the electron conductor comprises carbon cloth, carbon paper, carbon screen printed electrodes, carbon black, carbon powder, carbon fiber, single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, carbon nanotube arrays, diamond-coated conductors, glass carbon, mesoporous carbon, graphite, uncompressed graphite worms, delaminated purified flake graphite, high performance graphite, highly ordered pyrolytic graphite, pyrolytic graphite or polycrystalline graphite.

54. The biocathode of claim 47 wherein the cathode enzyme comprises bilirubin oxidase or superoxide dismutase.

56. A biofuel cell for generating electricity comprising:

a fuel fluid;

an anode; and

a biocathode of claim 47.

57. The biofuel cell of claim 55 wherein the cathode comprises a biocathode of claim 47.

58. The biofuel cell of claim 56 wherein the oxidant comprises oxygen or peroxide.