METHOD OF ACETATE HYDROCORTIZONE, ACETATE CORTISONE, METHYLPARAGYROXIBENZOATE, PROPYLPARAGHYROXIBENZOATE CHROMATOGRAPHIC SEPARATION BY REVERSE PHASE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY Russian patent published in 2018 - IPC G01N30/10 

FIELD: medicine; pharmaceuticals.

SUBSTANCE: invention relates to the field of chromatography and can be used in the pharmaceutical industry for quality control of medicinal products (ointment, cream). In the claimed method of chromatographic separation of hydrocortisone acetate, cortisone acetate, methyl parahydroxybenzoate, propyl parahydroxybenzoate by reversed phase high performance liquid chromatography, prepare mobile phase, where inject additionally a second organic modifier methanol for liquid chromatography in an amount comparable with the amount of acetonitrile for chromatography in proportions, respectively methanol for liquid chromatography, acetonitrile for chromatography, water: 200:240:560 v/v/v. Prepare solvent, consisting of acetonitrile for chromatography, tetrahydrofuran and water in a volume ratio of 20:20:60, then prepare test solution containing about 500 mg of an ointment or cream and 10.0 ml of the solvent. Prepare "placebo" solution containing 495 mg of excipients mixture, forming part of an ointment or cream in appropriate proportions and 10.0 ml of the solvent, then prepare hydrocortisone acetate reference solution, containing about 10.0 mg of a standard sample of hydrocortisone acetate and 100 ml of the solvent. Then dilute it by 1.0 ml of the solvent in a 10 ml flask and prepare the solution for the chromatographic system sensitivity test. Prepare stock solution of cortisone acetate, containing 10.0 mg of cortisone acetate reference sample and 100 ml of the solvent. Prepare stock solution of methyl parahydroxybenzoate, containing 8.0 mg of methyl parahydroxybenzoate reference sample or methyl paraben reference sample and 20 ml of the solvent, prepare stock solution of propyl parahydroxybenzoate, containing 10.0 mg of propyl parahydroxybenzoate reference sample or propyl paraben reference sample, and 100 ml of the solvent. Then prepare solution to test the suitability of chromatographic system, containing 5.0 mg of hydrocortisone acetate reference sample, 1.0 ml of cortisone acetate stock solution, 1.0 ml of methyl parahydroxybenzoate stock solution and 1.0 ml of propyl parahydroxybenzoate stock solution. Then, run chromatography system sensitivity test solution, chromatographic system suitability test solution, hydrocortisone acetate reference solution, 10 mcl each, getting at least three chromatograms, solvent, placebo solution and test solution on a liquid chromatograph with a UV spectrophotometric detector, with the following chromatographic conditions: column 250×4.6 mm, particle size 5 mcm, filled with octadecylsilyl silica gel sorbent, for example Zorbax Eclipse XDB C18, flow rate of 1.2 ml/min, column temperature 30°C, UV detector, 254 nm, then calculate the content of any single impurity in the preparation and total amount of impurities.

EFFECT: technical result is the development of chromatographic method for the separation of four components: hydrocortisone acetate, cortisone acetate, methyl parahydroxybenzoate and propyl parahydroxybenzoate.

1 cl, 1 dwg, 2 tbl