HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF PHENOLS USING A TYROSINASE-BASED AMPEROMETRIC BIOSENSOR DETECTION SYSTEM

A glassy carbon electrode was modified by co-immobilization of tyrosin ase and a conducting poly(1-vinylimidazole)-based osmium polymer on it s surface, The ability of this biosensor to function as a detector for the HPLC determination of phenolic compounds, such as p-aminophenol, phenol, p-cresol, catechol and p-chlorophenol, was then assessed, The mobile phases investigated were binary mixtures Of methanol and phosph ate buffer, The effects of operational parameters, such as the concent rations of the electrode-modifying compounds, i.e., the osmium polymer and the cross-linking agent, poly(ethylene glycol), the mobile phase flow rate, the working potential and the biosensor's short-term stabil ity were investigated and optimized, The biosensor exhibited a 100-200 -fold improvement in sensitivity and detection limit when compared wit h a UV/VIS spectrophotometric detector, The amperometric phenol biosen sor was able to detect catechol, phenol, p-cresol, m-cresol and four o ther phenolic compounds in cigarette filter tips.