Canagliflozin is an oral hypoglycemic drug recently formulated in combination with a biguanide, metformin hydrochloride, for improving its hypoglycemic action. Canagliflozin has one reported major degradation product, also metformin hydrochloride has one reported major degradation product, cyanoguanidine, and has a potential toxic impurity, melamine, that is reported to cause crystalluria that causes chronic kidney inflammation and nephrolithiasis leading to a renal failure. As per International Conference of Harmonization guidelines; a drug degradation product is classified as a type of drug impurities. Toxicity profiles of canagliflozin and metformin major degradation products were studied where in silico data disclosed toxicity too; the development of a specific chromatographic thin layer chromatographic assay was a must for quantification of such toxic related components along with the drugs in laboratory-prepared mixtures as a superior study. The proposed method was validated as per the International Conference of Harmonization and applied for the assay of Vokanamet tablets. The separation was achieved using acetone:ethyl acetate:acetic acid (8:2:0.2, by volume) as scanning eluted bands at 205 nm. For minimal environmental impact; greenness profile appraisal of the proposed assay was performed by three greenness assessment approaches; analytical Eco-Scale, Green Analytical Procedure Index, and Greenness metric approaches.
Keywords: canagliflozin; green; metformin; thin layer chromatography; toxic impurities.
© 2022 Wiley-VCH GmbH.