Rapid Detection of Illicit Material Within Simulated Seized Drug Samples by RADIAN™ ASAP Mass Detector

Significance of the topic

Rapid, reliable screening of seized drug samples is critical to forensic workflows because of rising drug use and the diversity of counterfeit and adulterated products. Fast identification minimizes public health risks, supports investigative timelines, and reduces laboratory backlog. Ambient ionization mass spectrometry methods that require minimal sample preparation can accelerate triage and guide confirmatory testing while preserving resources and personnel time.

Objectives and study overview

This application study evaluated the capability of the Waters RADIAN ASAP Mass Detector combined with SpectralWorks AnalyzerPro XD Software and the Waters Seized Drug Reference Library to rapidly detect and discriminate illicit or counterfeit paracetamol (acetaminophen) tablet samples in a simulated seized-drug context. Specific goals were to: (1) demonstrate fast identification of paracetamol in commercial and laboratory‑made counterfeit tablets, (2) compare two surface and solution sampling approaches (rubbing vs dipping), and (3) assess the technique’s ability to discriminate formulations (including detection of caffeine) using multivariate statistics.

Methods and applied methodology

Sample set and preparation:

• Simulated counterfeit tablets were manufactured in the lab using paracetamol and common tablet excipients (Kollitab DC 87, PROSOLV EASYtab SP, Starch 1500) with standard blending, sieving and single‑station tablet pressing procedures; one batch contained 1% w/w magnesium stearate.
• Commercial over‑the‑counter paracetamol tablets and one paracetamol/caffeine OTC product were included to represent authentic products.

Sampling approaches:

• Rubbing method: a cleaned glass capillary was rubbed across the tablet surface three times and introduced directly into the RADIAN ASAP source; five replicate analyses per sample.
• Dipping method (Waters seized drug protocol): tablets were pulverized, 1 mg subsampled, dissolved in 1 mL methanol and diluted to 25 µg/mL; capillaries were dipped ~1 mm for ~3 s and analyzed; five replicates per sample.

Mass spectrometry acquisition and processing:

• Data were acquired in full‑scan mode over m/z 50–600 at four cone voltages (15, 25, 35, 50 V) to gather complementary ionization/fragmentation information.
• Spectral processing and real‑time library matching were performed in AnalyzerPro XD, which combines forward/reverse matching, ion intensity thresholds, molecular mass checks and ion‑ratio consistency across voltages into a weighted confidence score (percentage) against the Waters Seized Drug Reference Library.
• Multivariate analysis (principal component analysis, PCA) and volcano/bar‑plot comparisons were used to evaluate formulation differences and identify marker species such as caffeine (m/z 195).

Used instrumentation

Instrumentation reported in the study:

• Waters RADIAN ASAP Mass Detector — compact benchtop ASAP source coupled to a mass detector, operated in direct analysis mode.
• SpectralWorks AnalyzerPro XD Software — real‑time library searching and statistical workflows.
• Sample preparation equipment — Turbula mixer, laboratory sieves (500 µm), single‑station tablet press (Riva Minipress), glass capillaries and standard glass vials.

Key results and discussion

Identification performance:

• Paracetamol was confidently identified in all samples. Using the rubbing (surface) method, library matches returned confidence scores ≥91% across samples. The dipping (solution) method gave improved confidence levels (96–99%), attributed to more consistent extraction and ionization.

Formulation discrimination:

• PCA on spectra acquired using the dipping protocol separated counterfeit laboratory‑made tablets from commercial OTC products, indicating sensitivity to excipient and formulation differences rather than only the active ingredient.
• Comparative statistical plots (volcano and bar charts) unambiguously showed caffeine (m/z 195) as a marker present in the paracetamol/caffeine sample and absent in comparator tablets.

Operational considerations:

• Collecting spectra at multiple cone voltages enhanced specificity by combining molecular and fragment information into a single confidence score.
• Surface rubbing offers a rapid, solvent‑free screening option but generally provides lower confidence than solvent extraction; dipping improves reproducibility at the cost of minimal sample preparation.

Benefits and practical applications

The RADIAN ASAP plus AnalyzerPro XD workflow offers several practical advantages for forensic triage:

• Fast turnaround with real‑time library matching allows near‑immediate screening decisions, suitable for high throughput or on‑site deployments.
• Minimal sample preparation (rubbing) reduces consumables and processing time; dipping provides higher confidence when needed.
• Compact benchtop footprint and user‑friendly software reduce training requirements and enable non‑expert operators to perform initial screens.
• Multivoltage acquisition and chemometric analysis enable discrimination of counterfeit versus authentic formulations and detection of specific adulterants or co‑formulated actives such as caffeine.

Future trends and potential uses

Opportunities and recommended directions for further development include:

• Validation with heterogeneous, real‑world seized materials spanning a wider range of APIs, cutting agents and novel psychoactive substances to evaluate robustness and false positive/negative rates.
• Expansion and continuous updating of curated spectral libraries to encompass new drugs, metabolites and common adulterants for improved identification coverage.
• Integration with mobile or field‑deployable setups for rapid onsite screening by law enforcement or harm‑reduction services.
• Automated workflows that fuse ASAP screening data with orthogonal confirmatory techniques (LC‑MS/MS, GC‑MS) to streamline casework triage and reporting.

Conclusion

The study demonstrates that the RADIAN ASAP Mass Detector combined with AnalyzerPro XD and a dedicated seized‑drug spectral library can rapidly and reliably identify paracetamol in both commercial and simulated counterfeit tablets and discriminate formulations based on excipient profiles. The dual sampling modes (rubbing and dipping) provide flexible trade‑offs between speed and confidence, and multivoltage acquisition improves specificity. Broader validation on authentic seized samples and continued library expansion would strengthen applicability in operational forensic settings.

References

1. UNODC. World Drug Report Key Findings. 2025.
2. Di Trana A., et al. Molecular Insights and Clinical Outcomes of Drugs of Abuse Adulteration: New Trends and New Psychoactive Substances. 2022.
3. Mistry N.S., Lee E., Hammond G. Analysis of Seized Drug Samples by RADIAN ASAP Mass Detector. Waters Application Note. 2026.