Amperometric biosensor for tyrosinase inhibitors in a pure organic phase
Abstract
The determination of benzoic acid, thiourea and 2-mercaptoethanol in three pure organic solvents, viz., chloroform, chlorobenzene and 1,2-dichlorobenzene, by using an amperometric cryohydrogel tyrosinase biosensor is described. Measurements were carried out with phenol as the enzyme substrate. Kinetic parameters (Ki and I50) were determined in the three solvents for various inhibitors. The sensor showed the most sensitive measurements to these inhibitors in pure chloroform. The solvent-induced deviation of the biosensor to thiourea was evaluated by means of Hill coefficients. The smallest deviation was observed in 1,2-dichlorobenzene, owing to the high hydrophobicity of this solvent. The nature of the inhibition process and its reversibility were also examined.