Rapid Determination of Pentazocine in Human Plasma and Urine by a Potentiometric Method

A fast potentiometric determination method has been reported for pentazocine in human plasma without complicated pretreatments using a coated-wire potentiometric selective electrode. The sensing membrane was made by incorporating of ion-association complexes of pentazocine cation and sodium tetraphenyl borate (NaTPB) in a polyvinyl chloride. The sensor exhibited fast, stable, and linear Nernstian response over the range of 510-5 to 0.1molL-1 pentazocine with a slope of 57.8mV per decade and with detection limit of 3.210-5molL-1. The proposed sensor has been used for determination of pentazocine in human plasma and urine.