Development of a method for isolating Efavirenz from a model urine mixture

Objective: to study the effect of various factors on the extraction of Efavirenz from solutions and to develop a method for its isolation, detection and quantification from urine. Materials and methods. Pharmaceutical substance-powder and Efavirenz tablets, which meet the requirements of regulatory documents, were analyzed. To develop a method for isolating Efavirenz from biological objects, liquid-liquid extraction and high-performance liquid chromatography (HPLC) were used. The results of experimental studies are statistically processed using the software package for Windows XP (Microsoft Excel) using Student's t-test. Differences were considered significant at a confidence level of p <0.05. Results. In order to optimize the methods, the conditions under which the highest yield of Efavirenz is achieved are studied: organic solvents - diethyl ether, dichloromethane; pH value - for diethyl ether pH = 3, for dichloromethane pH = 2; the electrolyte exhibiting a salting out effect is a sodium chloride solution of 20% (when isolated with diethyl ether), sodium chloride is a saturated solution (when isolated with dichloromethane); the multiplicity of extraction - triple extraction; extraction time - for three minutes with diethyl ether and for seven minutes with dichloromethane. Conclusion. The obtained results confirm method suitability, therefore, the technique can be recommended for chemical-toxicological and forensic-chemical analysis of the studied medicinal substance.

судебно-химический анализ, химико-токсикологический анализ, изолирование, эфавиренз, количественное определение, обнаружение, forensic chemical analysis, analytical toxicology, sample preparation, Efavirenz, quantitation, detection