Ultra Micro Determination of Sulphonamide Through Oxidative Coupling Reaction Using Diazotized Promethazine

The quantification of pharmaceutical compounds, particularly Sulphonamide, shows a significant challenge in analytical chemistry. This study determined an innovative method for the ultra micro determination of Sulphonamide utilizing an oxidative coupling reaction with diazotized promethazine. We analyzed the interaction of Sulphonamide with promethazine in the presence of potassium ferric cyanide in a basic medium, resulting in a colored product with maximum absorbance at 452 nm. Various factors including reaction medium, type of basic solution, and oxidizing agent were investigated to optimize the method. The proposed technique exhibited high sensitivity and stability, with minimal interference from foreign compounds. Additionally, the method was successfully applied for the determination of Sulphonamide in serum and urine samples. The nature of the formed azo dye and the stability constant were also studied, further validating the efficacy of the method. Overall, this method offers a reliable and efficient approach for the accurate determination of Sulphonamide, particularly in trace amounts, making it suitable for pharmaceutical analysis and medical research.