Tox Explorer Collection for LC-MS - FAQs

Significance of the Topic

Liquid chromatography–mass spectrometry (LC-MS) plays a critical role in forensic and clinical toxicology by providing sensitive, accurate, and high-throughput detection and confirmation of drugs and metabolites. High-resolution accurate-mass (HRAM) platforms enhance confidence in compound identification across diverse laboratory settings.

Objectives and Overview of the Article

The article introduces the Thermo Scientific Tox Explorer Collection, a turn-key LC-MS workflow designed for targeted toxicology screening. Its goals are to deliver validated chromatographic and mass spectrometric methods, an extensive spectral library, and comprehensive training to support forensic, clinical research, anti-doping, and reference laboratories.

Methodology and Instrumentation

The core workflow comprises:

• Vanquish Flex UHPLC with a standardized 0–12 min gradient and Accucore phenyl-hexyl column for broad compound separation.
• Q Exactive Plus hybrid quadrupole-Orbitrap MS for full-scan HRAM and data-dependent MS/MS acquisition.
• TraceFinder 5.1 software with a Compound Database and spectral library for targeted data processing and retention-time matching.

Sample preparation is adaptable, though the recommended quick-extraction protocol balances throughput and sensitivity. Any changes in chromatographic conditions require updating retention times in the database.

Main Results and Discussion

Validation experiments quantified 54 representative drugs of abuse at 0.1–1,000 ng/mL with mass accuracy within 5 ppm. Extracted ion chromatograms of four 54-compound mixtures demonstrated consistent peak shapes and retention times. The method accommodates SIM and PRM modes for targeted quantitation, acknowledging reduced scan rates when many ions coelute. The compound library currently holds over 1,500 analytes, with periodic updates and user-driven additions.

Benefits and Practical Applications of the Method

• Comprehensive targeted screening and confirmation in forensic, clinical, anti-doping, and reference laboratories.
• High confidence in identification through HRAM full-scan and spectral matching.
• Customizable database to include novel or emerging analytes.
• High throughput with thousands of injections per column, subject to routine maintenance.
• Included on-site or virtual training and support to accelerate implementation.

Future Trends and Applications

Planned expansions include triple quadrupole SRM methods for fast targeted assays, data-independent acquisition (DIA) on Exploris platforms, and integration with Compound Discoverer software. Incorporation of ion chromatography and gas chromatography is under consideration to extend analyte coverage. Continued spectral library updates will facilitate unknown compound discovery.

Conclusion

The Tox Explorer Collection offers a validated, adaptable LC-MS solution that streamlines targeted toxicology workflows. Its combination of HRAM instrumentation, comprehensive libraries, and training support makes it a versatile tool for modern forensic and clinical laboratories.

Reference

1. Current Guidelines for Drugs of Abuse.
2. National Forensic Laboratory Information System (NFLIS): data collection of drug chemistry results from local, State and Federal forensic laboratories.
3. Tox Explorer Collection Technical Note: Comprehensive, robust LC-MS/MS toxicology method for HRAM screening and quantitation of drugs.