A high-throughput multi-class liquid chromatography tandem mass spectrometry method for quantitative determination of licit and illicit drugs in whole blood

Abstract

An ultra-high-performance liquid chromatography tandem mass spectrometry confirmatory method using pneumatically assisted electrospray ionisation (UPLC-ESI-MS/MS) was developed for the simultaneous quantification of licit and illicit drugs in whole blood across multiple drug classes. The method was validated on 51 frequently detected drugs and metabolites in human ante-mortem and post-mortem whole blood. The generic sample treatment procedure was based on deproteinisation by a mixture of methanol and acetonitrile followed by ultrafiltration of the extract. Matrix-matched calibrants combined with isotope dilution of almost all substances were used for quantitative analysis. A high sample throughput was obtained by using a 96-well format. The total instrumental run-time between injections was 16 min. The relative intra-laboratory reproducibility standard deviations were generally below 8% and 15% at concentrations of 250 μg L⁻¹ and 5 μg L⁻¹, respectively. The mean true recoveries were in most cases greater than 90% for ante-mortem samples and greater than 80% for post-mortem samples. For most substances, the limits of detection and quantification were less than 1 μg L⁻¹ and 3 μg L⁻¹, respectively.