METHOD FOR MEASURING MASS CONCENTRATION OF METHYL ESTERS OF FATTY ACIDS IN BIOLOGICAL MEDIA BY GAS-LIQUID CHROMATOGRAPHY METHOD Russian patent published in 2021 - IPC G01N33/487 G01N33/483 G01N33/12 G01N33/49 G01N30/02 

FIELD: chemistry.

SUBSTANCE: invention relates to various fields of the national economy (medicine, chemical and pharmaceutical industries), wherein there is a demand for measuring the mass concentration of methyl esters of fatty acids (MEFA) in biological media, including animal and plant tissues, by the gas-liquid chromatography method. The method for measuring the mass concentration of methyl esters of fatty acids (MEFA) in biological fluids by the gas-liquid chromatography method includes extraction of lipids, methylation of fatty acids by means of interesterification of lipids in the presence of an acidic catalyst, extraction of MEFA, reduction of the extracts of lipids and MEFA by variants at atmospheric pressure or under a vacuum, identification and measurement of the mass concentration of methyl esters of 43 fatty acids in the range of 0.3 to 1,000 mcg/cm³ using gas-liquid chromatography by the internal standard method, wherein fluid media of saliva, hemolymph, tissues of plants, fish or animals are used as the biological media; homogenisation of tissue samples and weighing thereof with an accuracy of up to 0.0002 g is conducted in the process of sample preparation, followed by calculatin ` `4saqg the mass concentration of each MEFA in mcg/g by the formula:

wherein: X is the mass concentration of each MEFA in the sample, mcg/g; A is the ratio of the detector response areas for this MEFA to the standard; B is the calibration coefficient for this MEFA; C is the amount of the internal standard added 4to the sample weight, mcg; K is the coefficient of reduction of the measurement result to 1 g (K=1/analysis sample weight, g). The result is achieved by applying vacuum equipment, thus increasing the quantitative yield of MEFA by 1.2 ÷1.7 times, thereby increasing the sensitivity and accuracy of the method.

EFFECT: invention provides a possibility of isolating and quantifying the MEFA even in small doses of biological samples, with a low content of fatty acids in the sample.

1 cl, 6 tbl, 6 ex