METHOD OF EXTRACTING AZATHIOPRINE FROM BIOLOGICAL FLUIDS Russian patent published in 2013 - IPC G01N33/493 G01N33/49 G01N33/48 

FIELD: chemistry.

SUBSTANCE: analysed sample is treated with a protein-depositing reagent which is acetone; the extract is separated from the precipitate by filtering; acetone from the filtrate is evaporated in an air current at room temperature; the aqueous residue is diluted with water; the formed solution is treated with ammonium sulphate, extracted with 0.9 mol/dm³ of dimethyl phthalate solution in a 1,4-dioxane-chloroform mixture, taken in volume ratio of 1:1, with ratio of the aqueous phase to the organic phase of 5:1 by volume; the organic extractant is separated, and the amount of the analysed compound transferred to the extract is determined from the optical density of the extract which is diluted tenfold with 1,4-dioxane while measuring at wavelength of 279 nm.

EFFECT: high degree of extraction of azathioprine from biological fluids.

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