SOLUTIONS THAT MEET YOUR DEMANDS FOR FORENSIC TOXICOLOGY

Importance of the Topic

Forensic toxicology underpins legal and safety decisions by detecting drugs, volatiles, and metals in biological matrices. Rapid, reproducible, and sensitive methods are essential for driving-under-the-influence cases, workplace drug testing, postmortem investigations, and doping control. Advanced hyphenated techniques enhance throughput and specificity, enabling laboratories to screen large sample volumes with confidence.

Study Objectives and Overview

• Present a spectrum of analytical strategies for forensic toxicology applications.
• Compare sample preparation and instrumental methods for alcohols, cannabinoids, steroids, and other drugs of abuse in blood, urine, hair, and oral fluids.
• Demonstrate integration of headspace, two-dimensional GC, tandem MS, and CE-MSn workflows to maximize sensitivity, selectivity, and speed.

Methodology and Instrumentation

• Sample Preparation: Solid-phase extraction (SPE) for blood and urine; direct plasma headspace; enzymatic hydrolysis of conjugates; hair wash, digestion, and SPE.
• Derivatization: Pentafluoropropionic anhydride, HFIP, or BSTFA/TMCS for volatiles, cannabinoids, and steroid metabolites.
• GC Techniques:
  • Static headspace GC–FID using polar CP-Wax 52 CB column for ethanol, acetaldehyde, acetone, ethylene glycol in serum/plasma.
  • Automated headspace sampling with Agilent 6890N GC and G1888 sampler; dual DB-ALC1/DB-ALC2 columns for blood alcohol analysis (FID detection, 4–6 min cycle).
  • Two-dimensional GC with Deans switch and backflushing to protect columns and reduce runtime.
• GC–MS/MS:
  • Agilent 7890 GC + 7000/Triple Quadrupole MS operated in NCI-MRM mode for trace THCA in hair; LOD 0.002 pg/mg, LOQ 0.01 pg/mg, 7 min run.
  • Fast GC/MS/MS on VF-5ms column for 13 anabolic steroids in urine; 12 min total run.
  • GC–QQQ for THC, 11-OH-THC, THCA in blood (dynamic range 0.1–50 ng/mL for THC/11-OH; 1–100 ng/mL THCA; 6 min run).
  • High-flow Bond Elut Certify II SPE and backflushing GC–QQQ for broad toxicology drug screening in whole blood (up to 17 compounds, pg-level detection, 14 min run).
• CE–MSn:
  • Capillary electrophoresis coupled to ESI-ion trap (Agilent G1600A CE + 1100/LC-MSD Trap XCT) for 17 drug analytes in standard mixtures and porcine/bovine whole blood extracts.
  • Auto MSⁿ acquisition (MS, MS², MS³) with library matching for unequivocal drug identification in a single run.

Main Results and Discussion

• Headspace GC–FID achieved robust quantification of ethanol and related volatiles, with simple plasma prep and high reproducibility (RSD < 3%).
• Automated headspace sampling with dual columns provided sub-1% carryover, excellent repeatability, and fast cycle times (≤ 5 min) for forensic blood-alcohol analysis.
• GC–MS/MS in negative CI mode delivered ultra-trace detection of THCA in hair (LOD 0.002 pg/mg, LOQ 0.01 pg/mg) and compliant quantitation with linear R²
• Fast GC/MS/MS on VF-5ms enabled separation of 13 anabolic steroids in 12 min, with detection limits of 2–5 ng/mL in urine.
• GC–QQQ analyses of cannabinoids in blood achieved LODs of 0.1 ng/mL (THC, 11-OH-THC) and 1 ng/mL (THCA) and confirmed positive case samples at pg levels.
• CE–MSn separated 17 standard drugs by mobility; detection down to <20 ng/mL in spiked whole blood; matrix interferences were minimal, and Auto MSⁿ identification validated coeluting analytes.

Benefits and Practical Applications

• Integrated workflows reduce turnaround time: headspace GC, GC/MS/MS, and CE–MSn deliver both screening and confirmatory data in minimal injections.
• Backflushing and low-thermal-mass modules increase robustness and protect columns, lowering maintenance and downtime.
• Dual-column, heart-cut GC and tandem MS greatly enhance selectivity, crucial for complex matrices such as postmortem blood and hair digests.
• CE–MSn offers an orthogonal screening approach with high electrophoretic selectivity and MSⁿ confirmation, valuable for novel or designer drugs.

Future Trends and Possibilities

• Expansion of MSⁿ libraries for designer drugs and metabolites to enhance CE–MSn screening in forensic labs.
• Coupling ambient ionization techniques with MS/MS for rapid, on-site toxicology testing.
• Further miniaturization and automation of SPE and headspace prep to streamline sample throughput.
• Machine-learning integration for spectral deconvolution and real-time decision support in forensic workflows.
• Development of multi-analyte panels on hybrid LC–MS/MS and GC–MS/MS platforms for comprehensive toxicology screening using single injections.

Conclusion

A suite of advanced analytical methods—headspace GC–FID, two-dimensional GC, GC–MS/MS, GC–QQQ, and CE–MSn—has been validated for a wide range of forensic toxicology applications. These protocols deliver high sensitivity, selectivity, and throughput for blood alcohol, drug-of-abuse, steroid, and cannabinoid analyses in various biological matrices. Integration of screening and confirmatory data acquisition in single runs optimizes laboratory efficiency and evidence reliability.

References

• Hudson JC, Golin M, Malcolm M, Whiting CF. Qualitative analysis of drugs by CE–DAD. Can. Soc. Forens. Sci. J. 1998;31:1–29.
• Phan DT, Harrsch PB. Analysis of drugs of abuse by CE–ESI-MS. Agilent Application Note 5968-9221E.
• Quimby B. Improved forensic toxicology screening using GC/MS/NPD and DRS. Agilent Technologies 5989-8582EN.