Spectrophotometric determination of L-α-glycerylphosphorylcholine in pharmaceutical formulations and industrial equipment cleaning rinse water with the WAKO Phospholipids C assay kit

Abstract

A simple spectrophotometric method for the determination of L-α-glycerylphosphorylcholine in pharmaceutical formulations and industrial equipment cleaning rinse water using the enzyme glycerophosphocholine phosphodiesterase and the WAKO Phospholipids C assay kit was proposed. The method is based on the enzymatic hydrolysis of α-GPC to choline by glycerophosphocholine phosphodiesterase, the reaction of choline with the components of the assay kit, and the colourimetric determination of the formed product. The calibration graph is linear in the range from 1 to 40 mg/l of α-GPC, the molar attenuation coefficient is 1,110 m2/mol, the limit of detection is 1 mg/l, the limit of quantification is 3.3 mg/l, the method is selective with respect to the common excipients, shows a good accuracy (the relative uncertainty does not exceed 7%) and precision (the relative standard deviation does not exceed 5.5%), does not require lengthy sample preparation and sophisticated laboratory equipment and is suitable for the routine analysis of pharmaceutical formulations and industrial equipment cleaning rinse water.