Toxtyper: Detection of opioids and prescription drugs at Miami Dade

Significance of the Topic

In recent years the rise of illicit opioids and new psychoactive substances has posed a major challenge for forensic toxicology. The high potency of compounds such as fentanyl and its analogs has led to a sharp increase in overdose fatalities. Accurate and sensitive screening methods are essential for identifying these substances in postmortem specimens and for understanding their role in cause of death investigations.

Objectives and Overview

This study describes the development and validation of a targeted LC MSn screening method for the simultaneous detection of common prescription analgesics and illicit opioids, including fentanyl analogs, in postmortem whole blood, urine, brain and liver tissue. The method employs the Toxtyper open library concept and a scheduled precursor list to ensure both rapid updates and high sensitivity at sub part per billion levels.

Methodology and Instrumentation

• Sample Preparation Solid phase extraction of whole blood, brain and liver homogenates using mixed mode cartridges. Dual elution for acidic neutral and basic drugs followed by evaporation and reconstitution.
• Chromatography UltiMate 3000 RSLC system with Acclaim RSLC C18 column. Gradient elution from high aqueous to high organic over a total run time of eleven minutes.
• Mass Spectrometry Toxtyper LC Ion Trap MSn system with electrospray ionization in alternating polarity mode. Data dependent acquisition of full scan MS, MS2 and MS3 using a scheduled precursor list of 42 compounds.
• Data Processing Automated processing with embedded DataAnalysis software and customizable library editor. Spectral matching against an open library and manual review for validation.

Main Results and Discussion

The specialized scheduled precursor list reduced analysis time and improved sensitivity compared with the standard library approach. Thirty compounds were fully validated under SWGTOX guidelines. Limits of detection for 26 basic analytes ranged from 0.5 to 5 ng/mL in whole blood and four acidic drugs had limits from 50 to 500 ng/mL. MS2 and MS3 spectra at the LOD showed purity scores above 900. Stability tests over 48 hours in a refrigerated autosampler indicated no significant degradation. Selectivity trials with eighty non targeted drugs at high concentration showed no false positives. Carryover was eliminated by solvent blanks between high concentration injections. Postmortem matrix extracts from decomposed samples produced no interferences or false detections.

Benefits and Practical Applications

This targeted MSn approach delivers robust spectral data and low detection limits for a focused class of opioids. The rapid library update capability allows laboratories to respond quickly to emerging analogs. The method supports forensic casework by providing reliable qualitative identification in limited sample volume specimens and complex matrices.

Future Trends and Opportunities

With the continuous emergence of new fentanyl analogs and designer drugs, expanding and maintaining an open spectral library will remain crucial. Integration with high resolution mass spectrometry and automation of sample preparation could further improve throughput. Real time data sharing of spectral entries may accelerate method updates across laboratories. The approach could also be adapted for clinical toxicology and drug monitoring applications.

Conclusion

The validated LC MSn screening method using the Toxtyper system offers a sensitive and customizable solution for the detection of prescription analgesics and illicit opioids in postmortem specimens. By focusing on a scheduled precursor list and robust library matching, the method achieves sub ppb sensitivity, excellent selectivity and rapid adaptability to new psychoactive substances.

Reference

• Shoff EN Czentnar Z Kiehne A Comprehensive detection and identification of prescription analgesics and illicit opioids in postmortem specimens using Toxtyper Bruker Application Note 2017