Targeted screening with Library Searching of drugs of abuse by MTS measuring cocaine and related stimulants, amphetamines, opioids & benzodiazepines

Introduction

A multi-residue assay was developed measuring 90 drugs of abuse in addition to deuterated internal standards (32 compounds). Compounds measured included benzodiazepines, cocaine and related stimulants, amphetamines and opioids; in addition antipsychotic compounds were screened for also. The Multi-Targeted Screening (MTS) method was developed using the Shimadzu Forensic & Toxicology method package containing over 1200 compounds. Blood samples were prepared by QuEChERs and measured by MTS using a Shimadzu LCMS-8060 and results compared to validated MRM analysis from a Shimadzu LCMS-8050. MTS operates by acquiring data with 2 MRMs per compound with the addition of threshold triggered product ion scan MS/MS at three different collision energies. Each product ion spectrum is then combined into a single merged spectrum for automated library searching. There are 2 clear advantages of acquiring MRM triggered product ion spectrum data, the first is the higher confidence in compound identification as a result of library searching and the second is the quantitative data is near identical to a conventional 2 MRM method. This approach was evaluated in a routine clinical toxicology laboratory to detect and identify compounds in unknown samples.

May 11, 2018 GMT