A Validated Screening and Confirmation Method for 946 Drugs and Metabolites Using LC-QTOF-MS with SWATH Acquisition.

Abstract

A streamlined liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) method utilizing protein precipitation and filtration extraction was developed to achieve rapid and reliable screening and confirmation for blood and urine matrices. This method targets 946 drugs and metabolites across 35 drug classes via sequential window acquisition of all theoretical mass spectra (SWATH) acquisition with variable customized windows to enhance spectral clarity, and was validated per established guidelines to ensure high accuracy and reproducibility. Combined with complementary in-house methods, this approach meets and exceeds the testing requirements outlined in ANSI/ASB standards and recommendations for postmortem, drug-facilitated crime (DFC) and Tier I and II driving under the influence of drug (DUID) analyses. The method demonstrated efficient and sensitive performance, achieving limits of detection as low as 0.1 ng/mL. It accurately identified expected detections across 67 proficiency test samples and 224 authentic case samples, with high accuracy and reliability in the detection of both traditional drugs and novel psychoactive substances (NPS). The method employs an in-house built library and incorporates in-batch standards analyzed alongside case samples to ensure contemporaneous identification criteria, making it suitable for confirmation and reporting purposes. By expanding the analytical capabilities to include a vast range of analytes, this method improves the likelihood of identifying substances that may otherwise go undetected, and reduces the need for multiple separate tests, thereby enhancing the overall effectiveness of toxicological investigations.