Spectrophotometric Determination of Salbutamol by Oxidative Coupling Reaction with 1-Naphthylamine-4-Sulfonic Acid in the Presence of Potassium Per Sulfate

Abstract

Background: Oxidative coupling reactions are among the most important reactions that have wide applications in chemistry, and the oxidative coupling process involves the interaction of two or more organic substances in the presence of an oxidizing agent, where an oxidation process occurs for these substances forming intermediate compounds that interact with each other to form a colored product that can be determined by either spectrophotometric, polarographic, or various chromatographic methods and these reactions were used to quantify many different organic and inorganic compounds. In this article, the spectrophotometric determination of salbutamol was done by an oxidative coupling reaction with the reagent 1-Naphthylamine-4-sulfonic acid in the presence of potassium per sulfate. Objective: In this study, we developed a simple, rapid, sensitive, selective, and accurate UV-visible spectrophotometric method for analyzing salbutamol in pure drugs and pharmaceutical formulations. Materials and Methods: Based on oxidative reaction with 1-Naphthylamine-4-sulfonic acid at pH 11.24, form a yellow-orange colored product in alkaline medium has a maximum absorbance at 470 nm. The Beer's law is followed in the concentration range 5–23 μg/mL. Results: The product was stable for 60 min, molar absorptivity was found to be 0.8054 × 104 L·mol−1·cm−1, and sandal index was 0.0296 μg·cm−2 with a relative error (RE) of 0 to −0.79, and a relative standard deviation (RSD) of 0.54%–1.84%. Detection limit (DL) was 0.227 μg/mL, quantitative limit (QL) was 0.756μg/mL, correlation coefficient was 0.9998, and recovery was 99.51%, respectively. Conclusion: The method was found to be accurate and precise, as indicated by recovery studies which is up to 100% and relative standard deviation is not more than 2 that is good result. The proposed method has been successfully applied in the determination of preparations containing salbutamol.