Detection of 4-FMC, 4-MeO-α-PVP, 4-F-α-PVP, and PV8 in blood in a forensic case using liquid chromatography-electrospray ionization linear ion trap mass spectrometry

We present a case of fatal poisoning by 4-F-methcathinone (4-FMC; also called flephedrone), 4-methoxy-alpha-pyrrolidinopentiophenone (4-MeO-alpha-PVP), 4-fluoro-alpha-pyrrolidinopentiophenone (4-F-alpha-PVP), and alpha-pyr-rolidinohepatanophenone (PV8). In this study, we compared the mass spectra of 4-FMC, 4-MeO-alpha-PVP, 4-F-alpha-PVP, PV8, and alpha-pyrrolidinohexanophenone between LC-ESI-LIT-MS and GC-EI-MS analyses. Subsequently, we applied LC-ESI-LIT-MS for detection and quantification analyses of 4-FMC, 4-MeO-alpha-PVP, 4-F-alpha-PVP, and PV8 in human authentic whole blood samples. More specific mass spectra for the target compounds were obtained with the LC-ESI-LIT-MS qualitative analyses than with the GC-EI-MS analyses, indicating that LC-ESI-LIT-MS was more suitable for the qualitative analysis of cathinones. The LC-ESI-LIT-MS validation data showed moderately good linearity and reproducibility for the compounds in the quantitative analyses at the range of 1-500 ng/mL. The detection limits of four cathinones ranged from 0.1 to 1 ng/mL. The concentrations of 4-FMC, 4-MeO-alpha-PVP, 4-F-alpha-PVP, and PV8 in heart whole blood samples were 365, 449, 145, and 218 ng/mL, respectively. Those of the 4 cathinones in femoral vein whole blood samples were 397, 383, 127, and 167 ng/mL, respectively. We can then assume that the cause of death was acute poisoning by a combination of 4-FMC, 4-MeO-alpha-PVP, 4-F-alpha-PVP, and PV8. In this article, we present a detailed LC-ESI-LIT-MS procedure for detection and quantification analyses of 4-FMC, 4-MeO-alpha-PVP, 4-F-alpha-PVP, and PV8 in authentic human whole blood samples. (c) 2021 The Author(s). Published by Elsevier B.V. CC_BY_NC_ND_4.0

Automated summary

This case study presents a fatal poisoning involving several cathinones, detected and quantified using LC-ESI-LIT-MS in authentic human whole blood samples. The LC-ESI-LIT-MS method showed high specificity for qualitative analysis of cathinones compared to GC-EI-MS. Validation data revealed good linearity and reproducibility for quantitative analysis of the compounds.