Simultaneous Spectrophotometric Estimation of Amoxicillin Trihydrate and Ambroxal hydrochloride by Second Order Derivative Spectroscopy Method in Combined Dosage Form

The objective of the study was to develop a simple, accurate, precise and rapid UV spectrophotometric, second order derivative method for validation of amoxicillin trihydrate and ambroxal hydrochloride from combined dosage form. The validation was carried out by using ICH guidelines for the determination of amoxicillin trihydrate and ambroxal hydrochloride by using 0.1N hydrochloric acid as the solvent in combined dosage form. The proposed second order derivative method involves the measurement of absorbance of one drug at zero crossing point of other; hence wavelengths 241.8 nm and 221.1 nm were selected for the estimation of amoxicillin trihydrate and ambroxal hydrochloride respectively. The linearity of the proposed method was found in the concentration range of 10 to 100 μg/ml (r²= 0.9998) for amoxicillin trihydrate and 1 to 10 μg/ml (r²= 0.9997) for ambroxal hydrochloride respectively. The percentage mean recovery was found to be 100.129% for amoxicillin trihydrate and 99.928% for ambroxal hydrochloride respectively. The method was also statistically validated for its linearity, accuracy and precision. Both intra and inter day variations showed less percentage (%) RSD values indicating high grade of precision of this method.