Development of methods of chemical and toxicological analysis of Rifabutin in objects of biological origin

Objective: to develop a technique for isolating and identifying rifabutin for chemical and toxicological analysis from biological material. Materials and methods. The substance rifabutin, capsules Farbutin containing rifabutin 150 mg, ethyl alcohol 95%, hydrochloric acid solution 0.1 M, sodium hydroxide solution 0.1 M, purified water, ammonia solution 10%, solutions of ammonium sulfate 20%, ammonium sulfate saturated, sodium sulfate 5%, sodium sulfate saturated, sodium chloride 20%, sodium chloride saturated were used for analysis. Organic solvents: benzene, dichloromethane, diethyl ether, toluene, chloroform, ethyl acetate. The pH was determined using a universal ionometer It-1101. Isolation was carried out by liquid-liquid extraction, detection and quantification by spectrophotometric method in the ultraviolet region. The optical density was measured using a SF-2000 spectrophotometer in cuvettes with a layer thickness of 1 cm. Results. In the course of the study, the optical properties of rifabutin, and absorption spectra characterized by two absorption bands at 231±2 nm and 279±2 nm were studied, ethyl alcohol 95% and hydrochloric acid solution 0.1 M, concentration 0.002% as optimal solvents were determined. The effect of various factors on the extraction of rifabutin from aqueous solutions has been experimentally studied. The highest degree of extraction is achieved by dichloromethane at pH 2, in the presence of sodium chloride saturated solution, once for 3 minutes. Conclusion. Methods of isolation and quantitative determination of rifabutin by UV spectrophotometry in extracts from biological fluids and organs have been developed.