METHOD FOR SEPARATE DETERMINATION OF ASPARTIC ACID AND GLUTAMINE IN AQUEOUS SOLUTIONS Russian patent published in 2007 - IPC G01N31/16 C07C229/24 

FIELD: analytical chemistry of organic compounds useful in determination of protein fermentation, analysis of waste waters from pharmaceutical an food processing industries.

SUBSTANCE: claimed method includes graining agent in form of crystal lithium sulfate in amount of 20 mass % is added to aqueous solution of aspartic acid and glutamine. Solution is stirred, and mixture of hydrophilic solvents containing 20 % mass of isopropanol, 20 % mass of acetone, and 60 % mass of ethyl acetate is added in solution/solvent mixture volume ratio of 1:10. Obtained mixture is extracted, extract is separated and content of aspartic acid and glutamine is detected on the base of differential curve of potentiometric titration with KOH solution in anhydrous ethanol. Aspartic acid or glutamine content is evaluated on the base of recovery degree thereof (R, %), calculated as R = D.100/D+r, wherein D is distribution coefficient of aspartic acid or glutamine between solvent mixture and solution; r is ratio of equilibrium volumes of aqueous and organic phases.

EFFECT: improver method for separate determination of aspartic acid and glutamine due to application of three-component mixture of hydrophilic solvents.

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