Comparison between three amperometric sensors for phenol determination in olive oil samples

The analytical performance of two modified electrodes (a tyrosinase biosens or and a glassy carbon electrode (GCE) covered with poly[Ni(protoporphyrin IX)dimethyl ester]) in comparison with the bare electrode has been evaluate d in a flow injection system using standard solutions of oleuropein and oli ve oil samples. The tyrosinase biosensor appeared to be an appropriate devi ce for the selective determination of phenols, moreover it can be easily in corporated in an on-line system. This method was used to evaluate the stabi lity of the samples.