Voltammetric determination of penicillamine using a carbon paste electrode modified with multiwall carbon nanotubes in the presence of methyldopa as a mediator

A multiwall carbon nanotubes-modified carbon paste electrode (mwcnts/mcpe) was fabricated and used to study the electrooxidation of penicillamine (pa) by electrochemical methods in the presence of methyldopa (mdop) as a homogeneous mediator. the electrochemical oxidation of pa on the new sensor has been carefully studied. the kinetic parameters such as electron transfer coefficient,α,and catalytic reaction rate constant,k/h,were also determined using electrochemical approaches. the electrocatalytic oxidation peak current of pa showed a linear dependent on the pa concentrations and linear calibration curves were obtained in the ranges of 0.2-250.0 µm of pa concentration with square wave voltammetry (swv) method. the detection limit (3σ) was determined as 0.1 µm. this sensor was also examined as a fast,selective,simple and precise new sensor for voltammetric determination of pa in real samples such as drug and urine. © 2017 by school of pharmacy shaheed beheshti university of medical sciences and health services.