Electrochemical sensor for procaine based on a glassy carbon electrode modified with poly-amidosulfonic acid and multi-walled carbon nanotubes

Abstract

A glassy carbon electrode was prepared that was coated with a composite film containing electropolymerized poly(amidosulfonic acid) and multi-walled carbon nano- tubes. It was used to study the electrochemical response of procaine by differential pulse voltammetry. The results indicate that the electrode exhibits a remarkable improve- ment in the oxidation peak of procaine, and this led to a simple and sensitive method for the electroanalytical determination of procaine. The peak current is proportional to the concentration of procaine from 80 nM to 1.0 µM. The detection limit is 25 nM (S/N=3). The modified electrode was successfully applied to the direct determina- tion of procaine in pharmaceutical formulations.