METHOD OF DETERMINING VITAMIN A IN THE FORM OF RETINOL ACETATE IN ANALYZED SAMPLE Russian patent published in 2024 - IPC G01N33/82 G01N33/15 G01N30/00 

FIELD: biotechnology.

SUBSTANCE: disclosed is a method for determining vitamin A in the form of retinol acetate in a test sample, comprising dissolving a control sample solution with a known concentration of vitamin in isopropyl alcohol according to the proposed protocol, preparing the test sample, including liquid extraction of the object under investigation, sampling of the same volume from the prepared samples and their high-performance liquid chromatography and determination of vitamin content by calculation based on comparison of peak areas of samples of control and analyzed samples. Pre-analyzed sample is exposed in accordance with specified parameters in the proposed biorelevant medium of farm animals or birds with constant mixing on the bioreactor at rate of 50 rpm. Then, preset volume of ascorbic acid solution and water in ratio of 1 g: 10 ml is added to vitamin A solution aliquot, stirred, potassium hydroxide solution, water and ethyl alcohol are added in ratio of 2 g: 2 ml: 18 ml, stirred, held for 30 minutes in a water bath at 55–60 °C, the obtained mixture is cooled to 20 °C, after adding water for analysis, it is subjected to double extraction with two portions of hexane in a given ratio, hexane extracts are separated, combined and evaporated to dryness, then dissolved in isopropyl alcohol, and held for 10 minutes in a dark place. Samples of the same volume are taken from the obtained control and analyzed samples and high-performance liquid chromatography is carried out at eluent flow rate of 0.4 ml/min and wavelength of 328 nm and determining vitamin A content by calculation.

EFFECT: invention enables to assess digestibility feed microencapsulated vitamin A in the form of retinol acetate in the body of farm animals or birds.

3 cl, 5 tbl