Development and Validation of UV-spectrophotometric Procedures for Efavirenz Quantitative Determination

Efavirenz is a non-nucleoside reverse transcriptase inhibitor and attributed to the group of antiretroviral medicines used for treatment of HIV infection. For efavirenz determination the method of HPLC is widely used, but efavirenz is applied in high concentration and less sensitive methods of analysis such as spectrophotometry may be useful for its quantification. The aim is to develop UV-spectrophotometric procedures of efavirenz quantification and carry out step-by-step validation of the developed procedures. UV-spectra of efavirenz in 96% ethanol and 0.1 M sodium hydroxide solution have been investigated and the absorption maximums are observed at 247 nm and 267 nm respectively. The procedures of efavirenz quantitative determination by the method of UV-spectrophotometry have been developed using the mentioned solvents and wavelengths respectively. Their validation by such parameters as stability, linearity, accuracy and precision in the variants of the method of calibration curve, method of standard and method of additions has been carried out. All procedures of efavirenz quantitative determination are acceptable for application. The best linearity, accuracy and repeatability have been fixed for the procedure with application of 0.1 M sodium hydroxide solution as a solvent in the variant of the method of additions.