Quantification of U-47700 and its metabolites: N-desmethyl-U-47700 and N, N-didesmethyl-U-47700 in 12 autopsy blood samples employing SPE/LC-ESI-MS-MS

摘要

Purpose The paper presents a report on the comprehensive assessment of a novel synthetic opioid (NSO) termed U-47700, and its two metabolites: N-desmethyl-U-47700 and N, N-didesmethyl-U-47700 in autopsy blood samples taken from 12 cases of fatal poisonings. Methods The analysis of the examined samples was based on the solid-phase extraction/liquid chromatography-electrospray ionization-tandem mass spectrometry method, which was developed in the validation process. In the quantitative analytical studies, deuterium analytes analogs were used, namely U-47700-d_6 and N-desmethyl-U-47700-d_3. Results The validation parameters of the method were determined, including the limits of quantification on the 1 ng/mL level, calibration curves range of 1-1000 ng/ml, intra-assay precisions and accuracies of 1.1-20.2% and -18.9-9%, respectively, and inter-assay precisions and accuracies of 2.9-13.0% and -11.4-3.3%, respectively. The matrix effects and the extraction efficiencies were formed at the levels of 54.0-119% and 53.0-118%, respectively. The parent substance and its metabolites in blood samples have been shown to be relatively stable under various conditions within the 21-day study. The concentration levels demonstrated in the analyzed blood samples were: U-47700 in the range of 83-24,000 ng/mL, N-desmethyl-U-47700 in the range of 2.0-7520 ng/mL and N, N-didesmethyl-U-47700 in the range of 18-1947 ng/mL.