Novel membraneless amperometric peroxide biosensor based on a tetrathiafulvalene-p-tetracyanoquinodimethane electrode.
Amperometric biosensors for the detection of hydrogen peroxide are prepared by adsorbing peroxidase (POD, EC 1.11.1.7, lipophilized with caprylic aldehyde) to TTF-TCNQ/silicone oil paste electrodes. This is the first time a reductase is coupled to an organic conducting salt electrode. At -50 mV vs Ag/AgCl and pH 6.0, the current vs concentration function can be described by the enzyme kinetic Michaelis-Menten formalism. Stable signals are obtained within 10 s. The detection limit is typically in the low nanomolar range for H2O2. The enzyme stability under storage, standby, and various operation conditions is discussed.
Korell
U
U
Department of Organic Chemistry, Swiss Federal Institute of Technology (ETH), Zürich.
Spichiger
U E
UE
D015374:Biosensing Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized; D006571:Heterocyclic Compounds / Q000737:chemistry*; D006735:Horseradish Peroxidase; D007202:Indicators and Reagents; D009570:Nitriles / Q000737:chemistry*; D010084:Oxidation-Reduction; D013113:Spin Labels
D004800:Enzymes, Immobilized; D006571:Heterocyclic Compounds; D007202:Indicators and Reagents; D009570:Nitriles; D013113:Spin Labels; C013703:tetracyanoquinodimethane; D006735:Horseradish Peroxidase; C063887:tetrathiafulvalene