First identification of dapagliflozin in human hair: development of a new LC-MS/MS method.

Sodium-glucose cotransporter 1- inhibitors are a new class of drugs used for the treatment of type II diabetes. Due to their diuretic capabilities and the glycosuria they induce, these molecules cause effective weight loss that could attract the interest of a wider public than diabetics with all the health consequences knowing the adverse effects of these substances. In order to reveal a past exposure to these substances, hair analysis can be very useful especially in the medicolegal context. There are no data in the literature about gliflozin testing in hair. In this study, a method was developed for the analysis of three molecules belonging to the gliflozin family (dapagliflozin, empagliflozin and canagliflozin) using a liquid chromatography system coupled to tandem mass spectrometry. After decontamination with dichloromethane, gliflozins were extracted from hair following incubation in methanol in the presence of dapagliflozin-d5. Validation showed acceptable linearity for all compounds between 10 and 10,000 pg/mg, with LOD and LOQ at 5 and 10 pg/mg respectively. Repeatability and reproducibility were below 20 % at 3 concentrations for all analytes. The method was subsequently applied to the hair of two diabetic subjects under dapagliflozin treatment. In one of the two cases the result was negative, while in the second case the concentration was 12 pg/mg. Due to the absence of data, it is difficult to explain the absence of dapagliflozin in the hair of the first case. Physico-chemical characteristics of dapagliflozin could explain its bad incorporation in hair, making detection difficult even after daily treatment.