Simple Real-time Voltammetric Method for Captopril Determination in Pharmaceutical Formulation

A novel voltammetric assay for captopril (CAP) determination by using an electrochemically pretreated pencil graphite electrode (PGE*) is presented. The electrochemical oxidation reaction of CAP was investigated with PGE* by using cyclic voltammetry and linear sweep voltammetry techniques. CAP was electrochemically inactive at the non-pretreated pencil graphite electrode surface, while a sharp anodic wave with an anodic peak potential at around 200 mV resulted by using the PGE*. According to kinetic studies upon the electrode behavior, a new reaction mechanism for electrochemical oxidation of captopril is proposed. The sensor was examined as a selective, simple and precise new electrochemical disposable electrode for the determination of CAP in pharmaceutical samples in complex medical cases associated with sleep apnea, with good results.

An Integrative Medical Perspective on Novel Dopamine Detection Method

Dopamine is very important neurotransmitter and the rapid and effective methods for its determination are of great importance in fundamental medical research. A rapid voltammetric assay for dopamine (DA) detection in presence of ascorbic acid (AA) based on an electrochemically pretreated pencil graphite electrode has been investigated. Differential pulse voltammetry results showed two well-distinguished oxidation peaks for DA and AA at 0.369 V and 0.142 V, respectively, and the method was applied for DA determination without previous separation. The obtained detection limit for DA was 5.17 � 10-8 M. The method has been successfully applied for determination of DA in a pharmaceutical sample.