Development and Validation of a GC–MS-EI Method to Determine α-PHP in Blood: Application to Samples Collected during Medico-Legal Autopsies.

This article focuses on the development and validation of an analytical method for detecting and quantifying alpha-pyrrolidinohexanophenone (α-PHP), a synthetic cathinone and new psychoactive substance (NPS), in blood samples using solid-phase extraction (SPE) combined with gas chromatography–mass spectrometry–electron ionization (GC–MS–EI). The method demonstrated high selectivity, linearity (10–1,000 ng/mL), sensitivity (limit of detection 5 ng/mL; limit of quantitation 10 ng/mL), precision, and stability, and was successfully applied to 15 postmortem cases from Portugal, revealing α-PHP concentrations ranging from 15 to 227 ng/mL alongside various other drugs. The study highlights the increasing presence of α-PHP in forensic toxicology despite low overall NPS consumption in Portugal and emphasizes the method's utility for routine casework, especially in laboratories lacking more advanced instrumentation. Additionally, the procedure allows differentiation between α-PHP and its structural isomer α-pyrrolidinoisohexanophenone (α-PiHP), contributing to more accurate forensic analyses.