A New Potentiometric Urea Biosensor Based on Urease Immobilized in Electrosyntesised Poly(o-Phenylenediamine)

A potentiometric urea biosensor based on urease (Ur) electrochemical immobilisation by poly( o -phenylenediamine) (PPD) is proposed. Polymer films have been grown by cyclic voltammetry on a glassy carbon (GC) electrode, using an unconventional “upside-down” (UD) geometry. GC/Ur-PPD electrodes exhibit a rapid (5–10 s) and sensitive response to urea concentration and lifetime of at least 5 weeks. Work is in progress to optimise the sensor and study its behaviour in the presence of possible interferences