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Bioelectrocatalysis. Arkady A. Karyakin. Faculty of Chemistry, M.V. Lomonosov Moscow State University, Moscow, Russia. Bioelectrocatalysis. is an acceleration of electrode reactions by biological catalysts. Whole cells. Enzymes. Applications of bioelectrocatalysis. Fuel electrodes
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Bioelectrocatalysis Arkady A. Karyakin Faculty of Chemistry, M.V. Lomonosov Moscow State University, Moscow, Russia
Bioelectrocatalysis is an acceleration of electrode reactions by biological catalysts Whole cells Enzymes
Applications of bioelectrocatalysis Fuel electrodes (biofuel cells) Biosensors Electrosysthesis
BIOELECTROCATALYSIS P2 S2
How to involve enzymes in bioelectrocatalysis? Use of mediators: Direct bioelectrocatalysis:
Direct bioelectrocatalysis if electrochemistry is determined by the catalyzed reaction or/and redox activity of biocatalyst
Redox activity of oxidases E ≈ -0.064 В (NHE) FAD
Mediated bioelectrocatalysis – II generation biosensors A. E. G. Cass, G. Davis, G. D. Francis, H. A. O. Hill, W. G. Aston, I. J. Higgins, E. V. Plotkin, L. D. L. Scott, and A. P. F. Turner, Analytical Chemistry 56, 667-671 (1984).
Mediated bioelectrocatalysis – II generation biosensors B.A. Gregg, A. Heller. Anal. Chem. 62 (1990) 258
Wiring of glucose oxidase E = -0.195 mV (Ag|AgCl) Heller, A. Physical Chemistry Chemical Physics2004, 6, 209-216.
Glucose test • Therasense: • 0.3 µL of blood
Dehydrogenase catalysis > 500 enzymes
NAD+|NADH redox reaction • the lowest potential in aerobic organisms; • on bare electrodes the overvoltages exceed 1 Volt.
Toluidine Blue Methylene Blue Methylene Green Brilliant Cresyl Blue Neurtal Red Azur A Thionine
Toluidine Blue 2 0.1mA/cm -0.4 0.4 0.8 E, V Electropolymerized azines: a new class of electroactive polymers
Hypothesis on polyazine structure A.A. Karyakin, E.E. Karyakina, H.-L. Schmidt. Electroanalysis (1999) 11 149.
Catalysis of NAD+ reduction and NADH oxidation 0.1 mM NADH 0.1 mM NAD+
Equilibrium NAD+|NADH potential A.A.Karyakin, Yu.N.Ivanova, E.E.Karyakina Electrochem. Commun. (2003) 5, 677-80
Protein electroactivity Cytochrome C S.R. Betso, M.H. Klapper, L.B. Anderson. J. Am. Chem. Soc. 94 (1972) 8197-204. M.R. Tarasevich, V.A. Bogdanovskaya. Bioelectrochem. Bioenerg. 3 (1976) 589-95. M.J. Eddowes, H.A.O. Hill. J. Chem. Soc. , Chem. Commun. (1977) 71 P. Yeh, T. Kuwana. Chem. Lett. (1977) 1145-8 Niki K, Yagi T, Inokuchi H, Kimura K. JACS101 (1979) 3335-40.
ē ē Promoters for protein electroactivity gold M.J. Eddowes, H.A.O. Hill. J. Chem. Soc. , Chem. Commun. (1977) 71 P. Yeh, T. Kuwana. Chem. Lett. (1977) 1145-8
Direct bioelectrocatalysis Est = 1.2 V Berezin I. V., Bogdanovskaya V. A., Varfolomeev S.D., M.R. Tarasevich, A.I Yaropolov. Dokl.Akad.Nauk SSSR(Proc. Acad. Sci.) 240 (1978) 615-618
Iron-sulfur clusters HEM PQQ Enzymes for direct bioelectrocatalysis Others
Direct bioelectrocatalysis A.I Yaropolov, V. Malovik, Varfolomeev S.D., Berezin I. V. Dokl.Akad.Nauk SSSR(Proc. Acad. Sci.) 249 (1979) 1399-401
Direct bioelectrocatalysis A.I. Yaropolov, A.A. Karyakin, S.D. Varfolomeyev, I.V. Berezin. Bioelectrochem. Bioenerg. 12 (1984) 267-77
(Yaropolov A.I., Karyakin A.A., Varfolomeyev S.D., Berezin I.V. Bioelectrochem. & Bioenergetics 12 (1984) 267-277) BIOELECTROCATALYSIS by Th. roseopersicina hydrogenase (1), (3) - H2 ; (2) - Ar (3) - without active enzyme
Nernst’ equation for Equilibrium hydrogen potential (100% energy conversion)
How to involve oxidases in bioelectrocatalysis? • surface pre-treatment; • usingof promoters; • surface design by conducting polymers.
Fundamentals of direct bioelectrocatalysis Investigations of enzyme redox centers Redox switching of enzyme activity
Inorganic ion reducing bacteria Shewanellaputrefaciens Lactateas electron donor Insoluble Fe3+as electron acceptor
Electroactivity of Shewanellaputrefaciens A – air exposed cells B – air exposed with lactate C – no air, but at + 200 mV D – at +200 mV with lactate Kim, B. H.; Ikeda, T.; Park, H. S.; Kim, H. J.; Hyun, M. S.; Kano, K.; Takagi, K.; Tatsumi, H. Biotechnology Techniques1999, 13, 475-478.
Geobactersulfurreducens on graphite electrode Bond, D. R.; Lovley, D. R. Applied And Environmental Microbiology2003, 69, 1548.
Advantagesof bioelectrocatalysis: • a possibility for electrochemistry of complex organic reactions; • high efficiency at room temperature and moderate overvoltages; • achieve high specificity. Disadvantages: • inherent instability, • large dimensions • of biological catalysts.