METHOD FOR COULOMETRIC DETERMINATION OF WATER CONTENT IN AMPICILLIN TRIHYDRATE SUBSTANCE Russian patent published in 2017 - IPC G01N33/15 

FIELD: chemistry.

SUBSTANCE: invention relates to analytical chemistry and a method of determining water content in ampicillin trihydrate substance. Method involves dissolving a weighed portion of said substance in a background electrolyte "Aqua M^®-Kulon AG", then introducing into a cell an aliquot of a solution of ampicillin trihydrate substance weighing 0.5 g, performing iodine electrical generation at constant current 50 mA in background electrolyte "Aqua M^®-Kulon AG" in an anode chamber, "Aqua M^®-Kulon CG" in a cathode chamber on a platinum electrode, measuring time of reaching titration end point, calculating water content in aliquot by formula X = I×t×M/F, where I is current, 0.05 A; t is time for achieving titration end point, s; M is molar mass equivalent of water, 9.008 g/mol; F is Faraday constant, 96,485 C/mol, concurrently determining water in solvent and based on known formulae calculating water content in ampicillin trihydrate substance.

EFFECT: use of method with high accuracy enables to determine water in ampicillin trihydrate substance.

1 cl, 2 tbl, 1 ex