Paper spray mass spectrometry simplifies and expedites turnaround of drug toxicity screening

Significance of the Topic

Acute recreational drug toxicity is a frequent cause of emergency department presentations and can lead to serious health complications. Rapid, accurate identification and quantification of drugs in patient blood samples is critical to guide timely clinical decisions and improve patient outcomes. Traditional LC-MS workflows are too slow for point-of-care use, creating a need for faster, simplified methods.

Goals and Overview of the Study

King’s College London researchers teamed with Guy’s and St Thomas’ NHS Foundation Trust and Thermo Fisher Scientific to evaluate paper spray mass spectrometry (PS-MS) for emergency department drug toxicity screening. The primary goals were to validate PS-MS performance in dried blood matrices, assess linearity and sensitivity for key drugs, and optimize workflows for minimal sample preparation and rapid turnaround.

Methodology and Instrumentation

Human plasma samples with suspected acute drug toxicity were dried onto paper substrates. A rewetting solvent was applied, and a high voltage induced ionization for direct analysis by MS. Key steps included:

• Spotting and drying of blood samples on paper cartridges
• Application of rewetting and ionization solvents
• Direct sampling into the mass spectrometer without chromatographic separation
• Comparison to deuterated internal standards for quantification

Used Instrumentation

Researchers employed:

• Thermo Scientific VeriSpray PaperSpray ion source
• Thermo Scientific TSQ Altis Plus Triple Quadrupole mass spectrometer
• Tox Explorer SRM library with over 2,000 drug transitions

Main Results and Discussion

Proof-of-concept tests demonstrated:

• Excellent linearity (R2 > 0.99) for six target drugs across therapeutic and toxic concentration ranges
• Analysis time of 1–2 minutes per sample, enabling throughput of up to 240 samples in eight hours
• Sensitivity sufficient to detect trace levels of highly potent opioids such as fentanyl
• Minimal risk of cross-contamination due to single-use paper cartridges

These findings highlight PS-MS as a viable alternative to multi-step LC-MS workflows for rapid toxicology screening.

Benefits and Practical Applications

The PS-MS approach offers several clinical advantages:

• Rapid turnaround: results available in minutes
• High throughput: unattended batch runs and single-sample flexibility
• Minimal sample preparation: no liquid chromatography required
• Operational simplicity: reduced training and maintenance
• Quantitative accuracy: use of isotopic internal standards
• Environmental sustainability: lower solvent consumption and waste

This method can support emergency departments in delivering near-patient drug screening and adjusting treatment strategies more effectively.

Future Trends and Opportunities

Paper spray MS is highly adaptable to emerging clinical needs. The platform can incorporate new psychoactive substances into the SRM library as they appear, ensuring continued relevance. Future developments may include:

• Expanded panels for novel synthetic drugs
• Integration with hospital laboratory information systems
• Miniaturized or portable PS-MS instruments for true point-of-care deployment
• Automated sample tracking and data reporting

Ongoing research and collaboration will drive broader adoption and standardization of this technology.

Conclusion

This case study demonstrates that paper spray mass spectrometry simplifies and accelerates drug toxicity screening in emergency settings. The combination of rapid analysis, high throughput, and minimal preparation positions PS-MS as a transformative approach for clinical toxicology. Wider implementation could shorten result times from days to minutes, improving patient management and outcomes.

References

1. Toxicology in the emergency department: what’s new?
2. Thermo Fisher Scientific collaboration offers potential for faster, more efficient analysis of samples from drug toxicity patients, March 9, 2023