Sensitive phenol determination based on co-modifying tyrosinase and palygorskite on glassy carbon electrode

Abstract

A sensitive tyrosinase biosensor, based on co-modifying tyrosinase and palygorskite on glassy carbon electrode, was developed for phenol analysis. Palygorskite, a kind of natural one-dimensional clay with good biocompatibility, high specific surface area and porous morphology, works as a perfect matrix of enzyme. Tyrosinase retains its inherent bioactivity when immobilized in palygorskite, which leads to a high sensitivity of 1.897 A mol−1 L. The sensor response achieves 95% of steady-state-current in no more than 3 s, and the linear range of the bioelectrode spans the concentration of phenol from 5 × 10−8 to 1 × 10−4 mol L−1 with a correlation coefficient of 0.9992. The results show no apparent decrease in the response over 2 weeks, and about 80% of the response was retained after 2 months when the electrode was stored at 4–5 °C.