First Derivative Spectrophotometric Determination of Hostacycline and Oxytetracycline – Applications

Simple, selective and sensitive first order spectrophotometric method has been developed for the determination of hostacycline and oxytetracycline at pH 3.5. Linear calibration plots are obtained in the range of 10 to 60μg/ml for each of the tetracycline. The method is also extended for the resolution of their binary mixtures by using the zero-crossing method for evaluation of the derivative signal. The corresponding calibration plot is linear in the rage 10 μg/ml to 25μg/ml for each of the tetracycline. Regression equation, correlation coefficient and percentage recovery is reported in each case. The developed method has been successfully applied for the determination of hostacycline and oxytetracycline in pharmaceutical formulations, urine and honey. A notable advantage of the proposed method is that the method can be applied without any pretreatment of the samples.