Abstract
A rapid stability indicating LC method for Efavirenz enantiomer using RRLC
Author(s): P.Raghuram, I.V.Soma Raju, J.SriramuluA simple, sensitive isocratic LC method has been developed for the quantitative determination of Efavirenz enantiomer in bulk drug, used for the HIV Aids. The developed method is applicable for the enantiomer determination. Efficient chromatographic separation was achieved on a Chiralpak-IA stationary phase with simple mobile phase combination delivered in a isocratic mode and quantification was carried out using ultraviolet detection at 252 nmat a flowrate of 2.5mLmin-1. In the developedHPLCmethod the resolution between Efavirenz and its enantiomer was found to be greater than 4.0. Regression analysis shows an r value (correlation coefficient) of greater than 0.9999 for Efavirenz enantiomer. This method was capable to detect enantiomeric impurity of Efavirenz at a level of 0.05%with respect to test concentration of 0.2mgmL-1 for a 20 ïÂÂL injection volume. The inter day precision values for Efavirenz enantiomer was found to bewithin 5.0%RSD at its specification level. The method has shown good and consistent recoveries for Efavirenz enantiomer (99.7-102.7). The drug was subjected to stress conditions of exposure to Humidity, Photolysis and thermal degradation. The developed LC method was validated with respect to linearity, accuracy, precision.
