Development of a highly sensitive and selective spectrophotometric method for the determination of carvedilol in pharmaceutical and urine samples
A simple, sensitive, selective, accurate and cost-effective spectrophotometric method for the determination of CAR in pharmaceutical and urine samples was developed. The method is based on the reaction between carvedilol and nitrite. Factors affecting the reaction were concentration of the reagents, including hydrochloric acid, sodium nitrite and sodium hydroxide. The factors were optimized using a central composite design. In optimum conditions, two calibration curves at 250 and 278 nm were constructed with linear ranges of 0.05–0.20 and 1.5–3.5 mg L−1 and detection limits of 1.8 × 10−4 and 8.1 × 10−4 mg L−1, respectively. The application of the proposed method showed precise and accurate results. In complex urine samples, the method was free from interferences. Comparison with the reported methods for carvedilol determination using statistical characteristics revealed that the proposed method is over all superior.