Coomassie brilliant blue G 250 modified carbon paste electrode sensor for the voltammetric detection of dihydroxybenzene isomers.

In this present study, coomassie brilliant blue G-250 (CBBG) modified electrode was fabricated for the specific and simultaneous detection of three dihydroxybenzene isomers such as resorcinol (RS), catechol (CC) and hydroquinone (HQ). The fabrication of the modified electrode was carried out by electrochemical polymerization of CBBG on the surface of unmodified electrode. The surface structures of bare and fabricated electrode were studied by scanning electron microscope (SEM). The established electrode portrays the very fine interface with these isomers and displayed the sufficient sensitivity and selectivity. The specific parameters of pH solution, scan rate and varying the concentration of analytes were optimized at the modified electrode. The sensor process was originated to be adsorption-controlled activity and the low limit of detection (LOD) for RS and CC was attained at 0.24 and 0.21 µM respectively. In the simultaneous study, designed sensor clearly implies the three well separated anodic peaks for RS, HQ and CC nevertheless in unmodified electrode it failed. Also, the constructed electrode was applied for the real sample analysis in tap water and obtained results are agreeable and it consistent in-between 92.80-99.48%.