Abstract

UV-SPECTROPHOTOMETRIC ABSORBANCE CORRECTION METHOD AND ABSORBANCE RATIO METHOD FOR THE SIMULTANEOUS ESTIMATION OF RITONAVIR AND DARUNAVIR ETHANOLATE

Mrinalini Damle* and Ajinkya Deosthali

ABSTRACT

Two simple and rapid UV spectrophotometric methods have been developed for the estimation of Darunavir ethanolate and Ritonavir in combination. Method A is Absorbance Ratio Method which is based on measurement of absorption at maximum wavelength of Ritonavir i.e. 239 nm and iso-bestic point i.e. 251 nm. Method B is Absorbance correction method, at wavelengths 251nm and 267 nm. Linearity for detector response was observed in the concentration range of 10-50 μg/ml for the both drugs and both methods. The developed method was validated with respect to linearity, accuracy (recovery), precision and specificity. The accuracy of the methods was assessed by recovery studies of Darunavir ethanolate was found to be 100.83% and 98.25% for Method A and Method B respectively and Ritonavir was found to be 100.52% and 99.25% for Method A and Method B respectively. The results were validated as per ICH Q2 R1 guidelines and were found to be satisfactory.

Keywords: Darunavir ethanolate, Ritonavir, UV Spectrophotometry, Absorbance Correction method, Absorbance Ratio method.