Abstract

Dr. Wadher Shailesh*, Kalyankar Tukaram, Shivpuje Shivraj, Lamture Sima and Khandre Supriya

ABSTRACT

Stability indicating UV spectrophotometric methods for simultaneous estimation of amoxicillin trihydrate and metronidazole in bulk and in-house tablet has been developed by two methods. First method is simultaneous equation based on measurement of absorbance at 230 nm and 310 nm as two wavelengths selected for quantification of amoxicillin trihydrate and metronidazole. The second method is absorbance ratio based on the measurement of absorbance at iso-absorptive point at 237.3 nm and 310 nm as second wavelength selected as for quantification. Both methods obeyed Beer-Lambert’s law in the concentration range of 15-90 ?g/ml for amoxicillin trihydrate and 5-30 ?g/ml for metronidazole with correlation coefficient (r2) values 0.999 for amoxicillin trihydrate and 0.998 for metronidazole in method-I, whereas 0.998 for amoxicillin trihydrate and 0.998 for metronidazole in method-II. Both methods showed good accuracy and precision with % RSD less than 2. LOD and LOQ values were 0.349 ?g/ml and 1.06 ?g/ml for amoxicillin trihydrate and 0.215 ?g/ml and 0.652 ?g/ml for metronidazole in method-I, whereas 0.558 ?g/ml and 1.689 ?g/ml for amoxicillin trihydrate and 0.215 ?g/ml and 0.652 ?g/ml for metronidazole in method-II respectively. The % assay was found to be 99.85% and 99.86% in method-I, whereas 99.63% and 99.86% in method-II for amoxicillin trihydrate and metronidazole respectively. Stress degradation was studied in different acidic, basic, neutral, oxidative, photolytic and thermal condition.