Development of Multiwalled Carbon Nanotube Based Electrochemical Sensor for Reactive Azo dyes

Two reactive azo dyes Reactive yellow 84 (RY84) and Reactive Red 120 (RR120) were investigated voltammetrically using plain glassy carbon electrode (GCE) and multiwalled carbon nanotube modified GCE (MWCNT/GCE). Influence of pH, scan rate and concentration on voltammograms were studied. The irreversible oxidation process observed for both dyes was adsorption controlled. The surface characterization of the modified electrode in the absence and presence of dyes was done using scanning electron microscopy (SEM). A systematic study of the experimental parameters that affects differential pulse stripping voltammetry (DPSV) was carried out and the optimized experimental conditions were arrived. Under optimized conditions, stripping voltammetry procedure was developed for the determination of reactive dyes. MWCNT/GCE seems to present better responses than plain GCE and the limit of detection (LOD) was 0.6 mu g mL(-1) for RY84 and 0.3 mu g mL(-1) for RR120 on this modified system. Suitability of the differential pulse stripping voltammetric method using the developed Multiwalled carbon nanotube based sensor, for the trace determination of these textile dyes in real samples was also realized.