Application of classical methodsfor isolating 2-methoxyhydroxybenzene (guaiacol) from biological materials

Objective: the study of the features of isolating guaiacol from a biological material by classical methods. Materials and methods. The object of the study is 2-methoxyhydroxybenzene (guaiacol) (“Fluka” company), containing ≥98% of the main substance. Models of biological matrices for the preparation of artificial mixtures with guaiacol are liver tissue and kidney. Liquid-liquid extraction is considered as the main purification method. TLC, UV spectrophotometry and HPLC are used for identification. Evaluation of the quantitative content of 2-methoxyhydroxybenzene in the extracts was carried out by the method of UV-spectrophotometry. Results. This study was conducted on the comparative isolation of 2-methoxyhydroxybenzene (guaiacol) from biological materials by a number of classical methods: Stas-Otto’s, A.A. Vasilyeva’s, V.F. Kramarenko’s and P. Valov’s methods. The TLC, UV spectrophotometry and HPLC were used to identify the isolated analyte. Quantitative assessment of the isolated compound was performed by the method of spectrophotometry in the UV region (analytical wavelength 277 nm). A modified version of the A.A. Vasilyeva’s method was devised. It provided an additional stage of extraction purification of the isolated analyte consisting of the following: transformation of guaiacol as an ionized form from the chloroform extract into a water-alkaline solution (pH 12.5-13), acidification of the water-alkaline extraction with hydrochloric acid to pH 2-3 and extraction of the resulting molecular form of guaiacol into a layer of ethyl acetate. Conclusion. Based on the modified A.A. Vasilyeva’s method, a protocol for determining guaiacol in the tissues of cadaveric organs was developed. When the content of guaiacol in the biomaterial is 0.01-0.2%, this protocol allows to analyze (33.99-34.62) ± (5.84-7.35) % of the analyte in liver tissues and (34.87-35.73 ) ± (5.66-6.97)% in kidney tissues.

2-methoxyhydroxybenzene (guaiacol), classical isolation methods, modification of the А.А. Vasilyeva’s method, detection in biomaterial, chemical-toxicological analysis