11

Bioelectrochemistry: From Biofuel Bioelectrochemistry: From Biofuel Cells to Membrane ElectrochemistryCells to Membrane Electrochemistry

Valentin MirValentin MirččeskieskiInstitute of Chemistry

Faculty of Natural Sciences and Mathematics

“Ss. Cyril and Methodius” University, Skopje

Republic of Macedonia

22

Electricity production using living microorganisms

Studying the interrelation between the chemical and electrical

phenomena in living organisms

Major Goals:Major Goals:

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Galvanic CellGalvanic Cell

A Galvanic cell converts chemical energy into electricity.

44

Bacterial Fuel CellsBacterial Fuel Cells

A microbial fuel cell converts chemical energy, available in a bio-convertible substrate, directly into electricity.

55

Finneran, K.T., Johnsen, C.V. & Lovley, D.R. Int. J. Syst. Evol. Microbiol. 53, 669–673 (2003).

Disadvantages

Power outputs - miliwats. Yet no commercially applications

80% electron efficiency

Advantages

Electricity generation out of wastewater Glucose-poweredpacemakersBio-sensors, and nutrient removal systems

66

paraffin-impregnated graphite electrode

T-cells

-5.E-06

0.E+00

5.E-06

-0.6 -0.2 0.2 0.6 1

E vs Ag/AgCl (3 M KCl) / V

I/A

Lymphocytes Immobilized on a Graphite ElectrodeLymphocytes Immobilized on a Graphite Electrode

reference electrode counter electrode

Fluorescent image of cells attached to the electrode.

Cyclic Voltammetry

77

reference electrode

Electron Transport Catalyzed by a Redox MediatorElectron Transport Catalyzed by a Redox Mediator

paraffin-impregnated graphite electrode

adsorbed redox mediator

counter electrode

Redox Mediator2-palmytoilhydroquinone

88

Catalytic Electron Transfer Mechanisms from T-cellsCatalytic Electron Transfer Mechanisms from T-cellsE

LE

CT

RO

DE

EL

EC

TR

OD

E

HH22QQ

QQ

T-cellsT-cells(reduced form)(reduced form)

2e2e--

H2Q/Q - a redox catalyst

T-cellsT-cells(oxidized form)(oxidized form)

-4

-3

-2

-1

0

1

2

3

4

-0.7 -0.2 0.3 0.8 1.3 E vs Ag/AgCl (3 M KCl) / V

I /

H2Q

H2Q + T-cells

V. Mirceski et al. in press: Clinical Chemistry and Laboratory Medicine 

99

Electrochemistry at a Single CellElectrochemistry at a Single CellUltramicroelectrodesUltramicroelectrodes

Image of a disk ultramicroelectrode by electronic microscopy

Typical dimensions within the interval:

10-6 to 10-9 m

1010

Cartoon of a neuronal chemical synapse

Exocytose of NeurotransmittersExocytose of Neurotransmitters

Exocytose

1111

Amperometric Detection of Exocytotic EventsAmperometric Detection of Exocytotic Events

Series of single vesicular exocytotic events observed through amperometric oxidation of adrenaline molecules

From: C Amatore et al. ChemPhysChem 2003, 4, 147-154

1212

Scanning Electrochemical MicroscopyScanning Electrochemical Microscopy

1313

Patch ClampPatch ClampIon Transfer through Cellular MembranesIon Transfer through Cellular Membranes

1414

Protein-Film VoltammetryProtein-Film Voltammetry

1515

Protein-Film and Cyclic VoltammetryProtein-Film and Cyclic Voltammetry

1616

The electrode takes the place of one of the enzyme's physiological redox partners.

Controlling the electrode potential one controls the rate of the electron exchange

Controlling the rate of change of the electrode potential, one precisely controls the enzyme's access to substrate

Catalysis with Redox Active EnzymesCatalysis with Redox Active Enzymes

1717

Coupling of the Redox Chemistry with Ion Transfer at Cellular Coupling of the Redox Chemistry with Ion Transfer at Cellular MembranesMembranes

K+ channel complex that catalyzes a redoxreaction.

K+

S. H. Heinemann et al. Science STCE, 2006, 350, 33.

K+

1818

Voltammetry of Artificial MembranesVoltammetry of Artificial MembranesCoupled Electron-Ion Transfer ReactionCoupled Electron-Ion Transfer Reaction

Edge Plane Pyrolytic Graphite Electrode

Red Ox+XX--

Organic film

Aqueous electrolyteCat+X-

Reference electrode

- e-

XX--

Organic electrolyteTBA+X-

Counter Electrode

RedRed(o)(o) + X + X--(aq)(aq) ⇄⇄ Ox Ox++

(o)(o) + X + X--(o)(o) + e + e--

1919

SO42-

CH3COO-Br-

NO3-

SCN-

ClO4-

0 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800

10

15

20

25

30

35

40

45

50

55

E vs SCE / V

I / A

Role of the Transferring IonsRole of the Transferring Ionson the Redox Chemistry of the Membraneon the Redox Chemistry of the Membrane

SW voltammograms for the oxidation of a lutetium complex in the nitrobenzene SW voltammograms for the oxidation of a lutetium complex in the nitrobenzene membranemembrane

2020

Red Ox+X-

-e

X-

Edge Pyrolytic Graphite Electrode

Cholesterol Membrane at the Liquid|Cholesterol Membrane at the Liquid|Liquid Liquid InterfaceInterface

2121

-0.350 -0.250 -0.150 -0.050 0 0.050-7.5

-5.0

-2.5

0

2.5

5.0

7.5

E vs. SCE / V

I / A

1

40

ClOClO44--

Monitoring of the Cholesterol Membrane Formation Monitoring of the Cholesterol Membrane Formation with Cyclic Voltammetrywith Cyclic Voltammetry

2222

E / V-0.400 -0.200 0 0.100 0.300 0.400

-10

-7.5

-2.5

0

2.5

7.5

10I /

A

with cholesterol

no cholesterol

NONO33--

Cholesterol Facilitates the Transfer kinetics of ClOCholesterol Facilitates the Transfer kinetics of ClO44--, NO, NO33

-- and SCNand SCN--

2323

Q10 electrochemistryQ10 electrochemistry

2424

Q10 chemical transformation in a basic mediumQ10 chemical transformation in a basic medium

2525

Caclium complexation with Q10-hydroxylated Caclium complexation with Q10-hydroxylated derivativesderivatives

2626

Caclium complexation with Q10-hydroxylated Caclium complexation with Q10-hydroxylated derivativesderivatives