METHOD OF DETERMINING PROCAINE IN BLOOD PLASMA Russian patent published in 2014 - IPC G01N33/15 G01N33/50 G01N30/06 

FIELD: chemistry.

SUBSTANCE: invention relates to biology, forensic and analytical chemistry and specifically to methods of determining procaine in blood plasma. The method comprises adding sodium fluoride to blood plasma containing procaine to achieve concentration of 10 mg/ml; treating the obtained mixture with acetone; separating the extract from the precipitate by filtering; evaporating acetone from the filtrate in an air current at room temperature; diluting the aqueous residue by adding water; saturating the obtained solution with ammonium sulphate; alkalising with an ammonium buffer solution to pH 9.0-9.5; extracting twice with portions of an organic extraction agent in the form of 30% camphor solution in methyl acetate, with ratio of the aqueous to the organic phase of 1:1 by volume; separating the organic extracts; combining; evaporating the solvent from the combined extract in an air current at room temperature; chromatographing the residue in a thin layer of silica gel STKH-1A on Sorbfil PTSKH-AF-A-UF plates, using a dichloromethane-ethanol mobile phase in ratio of 6:4 by volume; developing the chromatogram in UV light; eluting the analysed substance from the sorbent with a mixture of acetonitrile-methanol-0.025 M potassium dihydrogen phosphate solution with pH 3.0 in ratio of 10:10:90 by volume; chromatographing by HPLC method using a reversed-phase sorbent Nucleosil C18, a polar mobile phase acetonitrile-methanol-0.025 M potassium dihydrogen phosphate solution with pH 3.0 in ratio of 10:10:90 by volume and a UV detector; measuring optical density at wavelength 298 nm and calculating the amount of the analysed compound from the area of the chromatographic peak.

EFFECT: method improves sensitivity of determination.

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