Seamless automated sample preparation and analysis of DUID samples using high-resolution DIA QTOF library screening

Significance of the Topic

In roadside or emergency situations, rapid and reliable detection of drugs and alcohol in biological fluids is critical for legal and clinical decision-making. Oral fluid sampling offers a non-invasive, easily collected matrix providing timely insights into recent substance use. Integrating automated sample preparation with high-resolution liquid chromatography–mass spectrometry (LC–MS) improves throughput, consistency and confidence of Driving Under the Influence of Drugs (DUID) screening.

Study Objectives and Overview

This work evaluates an automated workflow combining Shimadzu’s CLAM-2030 sample preparation station and a high-resolution DIA QTOF LC–MS system for the analysis of oral fluid DUID samples. Key goals included comparing this approach against a validated QuEChERS/triple quadrupole method and demonstrating both targeted and retrospective screening capabilities using MS/MS libraries.

Methodology and Instrumentation

The automated platform (CLAM-2030) performed protein precipitation, filtration and sample transfer with stable isotope-labeled internal standards. Samples were injected onto a Shim-pack Velox Biphenyl column at 0.3 mL/min. High-resolution QTOF MS (LCMS-9030) acquired full MS and DIA-MS/MS scans (m/z 70–1000) with 20 Da windows and collision energy spread. A reference triple quadrupole system (LCMS-8050) with validated QuEChERS protocol provided comparative data. All workflows employed the same internal standards and chromatographic conditions.

Key Results and Discussion

Regression analysis between the automated QTOF and manual triple quadrupole methods for cocaine and benzoylecgonine yielded a slope of 0.96 and R2 = 0.91, indicating excellent agreement. Targeted screening reliably detected CAO panel compounds (cocaine, amphetamines, opioids) down to low ng/mL levels. Library-based MS/MS matching achieved high confidence using accurate mass (<5 ppm), isotope fidelity, retention time alignment and spectral similarity scores. Retrospective untargeted analysis of DUID samples uncovered additional heroin-related markers (noscapine, codeine), illustrating the value of data reprocessing without reacquiring samples.

Benefits and Practical Applications

• Non-invasive and rapid oral fluid collection supports on-site decision making.
• Automated prep reduces manual steps, minimizes variability and increases throughput.
• High-resolution DIA QTOF provides accurate mass, isotopic and retention data for robust identification.
• MS/MS library screening ensures high reporting confidence and enables retrospective searches.
• Workflow suits emergency and forensic laboratories requiring quick, reliable results.

Future Trends and Potential Applications

• Expansion to broader drug panels and emerging psychoactive substances via spectral libraries.
• Integration of advanced data analytics and AI algorithms for real-time suspect screening.
• Miniaturized and field-deployable automated sample prep coupled with portable MS platforms.
• Combining multi-omic approaches and biomarker discovery in driving impairment studies.

Conclusion

The study demonstrates a seamless, fully automated sample preparation and high-resolution DIA QTOF workflow for DUID oral fluid analysis that matches traditional methods in precision and sensitivity. The added benefits of spectral library screening and retrospective data mining enhance reporting confidence and broaden the analytical scope for forensic and clinical toxicology.

References

No references provided in the original text.