Transcript Slide 1

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
Enzymes
Whole cells
Applications of bioelectrocatalysis
Fuel electrodes
(biofuel cells)
Biosensors
Electrosysthesis
Enzyme
bioelectrocatalysis
BIOELECTROCATALYSIS
S2
P2
How to involve enzymes in
bioelectrocatalysis?
Use of mediators:
Substrate
Oxidoreductase
M ox
M red
Electrode
Direct bioelectrocatalysis:
S
-e
Oxidized
Substrate
P
Direct bioelectrocatalysis
if electrochemistry is determined by
the catalyzed reaction or/and redox
activity of biocatalyst
Oxidase catalysis
Oxidase
Analyte
O2
Oxidized
Analyte
H2O2
Redox activity of oxidases
H
N
O
N
N
N
H
2e
N
2H+
N
N
H
H
O
O
N
O
E ≈ -0.064 В (NHE)
O
HN
O
N
N
CH3
N
CH3
CH2
NH2
HO C H
HO C H
N
HO C H O
H2C O
N
O
P O
P O CH2
ONa
ONa
HO
N
O
N
OH
FAD
Mediated bioelectrocatalysis
– II generation biosensors
Glucose Oxidase
Glucose
+
Fc
Gluconic
acid
Fc
Fe
Electrode
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).
Glucose tests
•
Accu-Chek Complete BG System(Boehringer Mannheim)
•
Accu-Chek Easy(Boehringer Mannheim)
•
Accu-Chek Instant(Boehringer Mannheim)
•
Accu-Chek Instant Plus(Boehringer Mannheim)
•
Autolet® II Clinisafe(Owen Mumford)
•
Autolet® Lite Starter Pack(Owen Mumford)
•
Blood Glucose Strips(Roche)
•
Exatech®(Medisense)
•
Fingerstix Lancets(Bayer)
•
Glucofilm™ Test Strips(Bayer)
•
Glucose Control Solution(Roche)
•
Glutose®(Roche)
•
Lifescan One Touch® Basic™ System(Johnson & Johnson)
•
Medipoint Blood Lancets(Medipoint)
•
Monolet Lancet(Kendall-Sherwood)
•
Soft-Touch® II(Boehringer Mannheim)
•
Softclix(Roche)
•
Unilet Long-Body™ Lancets(Owen Mumford)
•
Unistik™-2(Owen Mumford)
Mediated bioelectrocatalysis
– II generation biosensors
+/2+
Os
+/2+
Os
+/2+
Os
Glucose
+/2+
Os
_
Os
e
hydrogel
+/2+
Gluc. ac.
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 Physics 2004, 6, 209-216.
Glucose test
Therasense:
0.3 µL of blood
Dehydrogenase catalysis
Dehydrogenase
Substrate
+
NAD(P)
> 500 enzymes
Product
NAD(P)H
NAD+|NADH redox reaction
O
O
C
C
NH2
N+
R
2eH+
NH2
N
R
 the lowest potential in aerobic organisms;
 on bare electrodes the overvoltages exceed 1 Volt.
N
H3C N
H3C
N CH3
CH3
S
N
H3C N
H3C
H2N
Methylene Blue
Methylene Green
S
NO2
N CH3
CH3
N
S
H2C
N
H2N
S
H2C
N
H2N
O
H2C
N
H2N
N
Toluidine Blue
N CH3
CH3
Brilliant Cresyl Blue
N CH2 CH3
CH2 CH3
Neurtal Red
Azur A
N CH3
CH3
H
N
H2N
S
Thionine
NH2
N CH3
CH3
Electropolymerized azines: a new
class of electroactive polymers
Methylene Blue
Toluidine Blue
Neutral Red
2
0.1 mA/cm
0.1mA/cm
2
0.5 mA/cm
-0.8
-0.4
0.8
E, V
-0.4
1.2
0.6
E, V
2
0.4
0.8
E, V
Hypothesis on polyazine structure
CH3
H3C N
S
H
N
N CH
3
N
H3C N
S
N
H3C N
H3C
S
N CH3
CH3
N CH3
CH3
A.A. Karyakin, E.E. Karyakina, H.-L. Schmidt. Electroanalysis (1999) 11 149.
+
NAD
Catalysis of
reduction
and NADH oxidation
j, A cm
-2
0.1 mM NADH
1
0
-0.60
-0.55
E, V
-1
0.1 mM NAD+
potential
j, A cm
-2
Equilibrium
+
NAD |NADH
1.0
0.5
0.0
-0.60
-0.55
-0.50
E, V
-0.5
A.A.Karyakin, Yu.N.Ivanova, E.E.Karyakina Electrochem. Commun. (2003) 5, 677-80
Direct enzyme
bioelectrocatalysis
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. JACS 101 (1979) 3335-40.
gold
Promoters for protein electroactivity
N
N
ē
ē
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

O2  4H  4e  2H 2O
Laccase
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
Enzymes for direct bioelectrocatalysis
Iron-sulfur clusters
HEM
PQQ
Others
Direct bioelectrocatalysis

H 2O2  2H  2e  2H 2O
Peroxidase
A.I Yaropolov, V. Malovik, Varfolomeev S.D., Berezin I. V.
Dokl.Akad.Nauk SSSR (Proc. Acad. Sci.) 249 (1979) 1399-401
Direct bioelectrocatalysis

2H  2e 
 H 2
Hydrogenas e
A.I. Yaropolov, A.A. Karyakin, S.D. Varfolomeyev, I.V. Berezin.
Bioelectrochem. Bioenerg. 12 (1984) 267-77
BIOELECTROCATALYSIS
by Th. roseopersicina hydrogenase
H 2  2e  2H 
2H   2e  H 2
(1), (3) - H2 ; (2) - Ar
(3) - without active enzyme
(Yaropolov A.I., Karyakin A.A., Varfolomeyev S.D., Berezin I.V.
Bioelectrochem. & Bioenergetics 12 (1984) 267-277)
Equilibrium hydrogen potential
(100% energy conversion)
Nernst’ equation for

H2  2 H  2 e
How to involve oxidases in
bioelectrocatalysis?
• surface pre-treatment;
• using of promoters;
• surface design by conducting polymers.
Fundamentals of direct
bioelectrocatalysis
Investigations of enzyme
redox centers
Redox switching of
enzyme activity
Direct
bioelectrocatalysis by
intact cells
Principal structure of bacterial
cells
Inorganic ion reducing bacteria
Shewanella putrefaciens
Lactate
Insoluble Fe3+
as electron donor
as electron acceptor
Electroactivity of Shewanella putrefaciens
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 Techniques 1999, 13, 475-478.
Geobacter sulfurreducens on graphite electrode
Bond, D. R.; Lovley, D. R. Applied And Environmental Microbiology 2003, 69, 1548.
Advantages of 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.