Selective Electrochemical Determination of Dopamine Using Thioglycolic Acid Modified Gold Electrode

Abstract

Dopamine is a crucial catecholamine neurotransmitter and extracellular messenger distributed in the mammalian central nervous system and renal systems. It can be detected electrochemically upon its oxidation on an electrode surface. Thus, this study was aimed to investigate the Selective electrochemical method for the detection of Dopamine, based on Thioglayolic acid modified gold electrodes. A selective electrochemical method for detection of Dopamine (DA) was developed, based on Thioglycolic acid (TGA) modified gold (Au) electrode. Characteristics of the modified electrode towards the oxidation of Dopamine in 0.1M Phosphate Buffer Solution (PBS) of pH 8.0 were studied. Several factors: the effect of pH, Interferences and scan rate that affect the electro catalytic activity were studied. The electrochemical behaviour of DA at the modified gold electrode was studied by cyclic voltammetry and a comparison was made between a bare and modified gold electrode in pH 8.0 PBS. Having its unique properties TGA modified gold electrode showed excellent linear characteristic responses in the range of 0.05-100 µM. The limit of detection is 0.07µM. In addition, the developed TGA modified gold electrode shows good repeatability. At the end it was successfully tested for determination of DA in DA injection sample.