Author(s): K. Venkata Sowmya, K. Ravishankar, D. Peer Basha and G.V.N. Kiranmayi
Caffeine and Sodium benzoate present in Caffeine and Sodium Benzoate injection was estimated by isoabsorption assay method using UV spectrophotometer. Maximum absorbance of Caffeine and Sodium Benzoate was recorded at 273nm and 224nm and the isobestic point is at 242nm. Each ml of injection solution consists of 125mg of caffeine and 125mg of sodiumbenzoate, a concentration of 10µg/ml of Caffeine and Sodium Benzoate was prepared and absorbance was recorded at 273nm and 224nm. Pure Sodium Benzoate, Caffeine solutions were prepared at concentration of 20µg/ml and the absorbance is measured in the region of 300-200nm.