title: A novel L-lactate-selective biosensor based on flavocytochrome b2 from methylotrophic yeast Hansenula polymorpha.
abstract: A novel amperometric biosensor highly selective to L-lactate has been developed using L-lactate-cytochrome c oxidoreductase (flavocytochrome b2) isolated for the first time from thermotolerant methylotrophic yeast Hansenula polymorpha as biorecognition element. Different immobilization methods and low-molecular free-diffusing redox mediators have been tested for optimising the electrochemical communication between the immobilized enzyme and the electrode surface. Moreover, the possibility of direct electron transfer from the reduced form of FCb2 to carbon electrodes has been evaluated. The bioanalytical properties of FCb2-based biosensors, such as signal rise time, dynamic range, dependence of the sensor output on the pH value, the temperature and the storage stability were investigated, and the proposed biosensor demonstrated a very fast response and a high sensitivity and selectivity for L-lactate determination.
authors.affiliation: Department of Cell Regulatory Systems, Institute of Cell Biology, Drahomanov Street 14/16, 79005 Lviv, Ukraine.
authors.forename: Oleh
authors.initials: O
authors.lastname: Smutok
authors.forename: Galyna
authors.initials: G
authors.lastname: Gayda
authors.forename: Mykhailo
authors.initials: M
authors.lastname: Gonchar
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schuhmann
mesh_terms: D015374:Biosensing Techniques; D004566:Electrodes; D042844:L-Lactate Dehydrogenase (Cytochrome); D019344:Lactic Acid / Q000032:analysis*; D010843:Pichia / Q000201:enzymology*
chemical_list: D019344:Lactic Acid; D042844:L-Lactate Dehydrogenase (Cytochrome)