Forensic Screening of Non-Derivatized Drugs in Urine by GCxGC TOF-MS

Reliable identification of drugs of abuse in complex biological matrices remains a critical challenge in forensic and toxicology laboratories. In this on‑demand webinar, John Heim and Joe Binkley of LECO Corporation present advanced GC‑MS strategies for urine drug screening using time‑of‑flight mass spectrometry (TOF‑MS) and comprehensive two‑dimensional gas chromatography (GCxGC‑TOF MS).

The first portion of the webinar focuses on an exploratory study demonstrating the feasibility of automated solid‑phase microextraction (SPME) coupled with GCxGC‑TOF MS for urine drug screening without derivatization. The presenters explain how enhanced chromatographic peak capacity, fast TOF acquisition rates, and robust deconvolution enable part‑per‑billion detection of drugs from multiple classes, even in heavily matrix‑laden samples. Calibration results show strong linearity across a wide concentration range, supporting the method’s potential for both screening and quantitative workflows.

The second portion of the session shifts to rapid drug identification using one‑dimensional GC‑TOF MS, highlighting fast screening methods, automated peak finding, and confident library matching using classical electron ionization (EI). Real‑world forensic examples—including drug residues on cotton swabs and characterization of unknown compounds in herbal incense—demonstrate how TOF‑MS, combined with optional chemical ionization (CI), supports molecular weight confirmation and structural elucidation of unknowns.

Together, these case studies illustrate how TOF‑MS–based workflows improve detection, reduce sample preparation requirements, increase throughput, and enhance confidence in drug identification for forensic and toxicological applications.

Presented 24 June 2010.