Contaminant Analysis by DPiMS™-2020 (3): Detection of Sleeping Pills in Beverages

Importance of the Topic

Beverage contamination by pharmaceuticals poses significant health risks and creates challenges for routine monitoring. Rapid, straightforward screening methods are essential for forensic investigations, quality control in the food and beverage industry, and public safety enforcement.

Objectives and Study Overview

This study assessed the potential of probe electrospray ionization mass spectrometry (PESI-MS) using the DPiMS-2020 platform to rapidly detect sleeping pill active ingredients and excipients in beverages. The goal was to establish a minimal-preparation workflow suitable for high-sensitivity screening.

Methodology and Instrumentation

Four commercial sleeping pill formulations (A–D) were dissolved in distilled water and spiked into four beverages (α, β, γ, δ). Each sample was mixed with 2-propanol, and 9 µL aliquots were deposited on a dedicated probe plate. The DPiMS-2020 direct probe ionization mass spectrometer acquired data in both negative and positive ion modes under optimized drive and acquisition settings to maximize detection sensitivity.

Used Instrumentation

• DPiMS-2020 Direct Probe Ionization Mass Spectrometer
• Probe Electrospray Ionization (PESI) Source Module
• Dedicated Sample Plate and Stainless-Steel Probe

Main Results and Discussion

In aqueous solutions, active drug ions (m/z 343, 345, 314, 308) and lactose excipient ions (m/z 365, 381, 707) were readily detected with intensities reflecting tablet content. When pills were spiked into beverages, detection of active ingredients varied markedly by matrix, with some beverages suppressing drug ion signals. However, lactose ions provided reliable markers of contamination even when drug signals were not observed. Comparative analysis across beverages α–δ highlighted the influence of beverage composition on ionization efficiency and signal suppression.

Benefits and Practical Applications of the Method

• Minimal sample preparation and rapid analysis turnaround
• High sensitivity for both drug molecules and excipient markers
• Effective screening tool for unknown adulterants in beverages
• Applicable to forensic laboratories, quality control, and regulatory inspections

Future Trends and Opportunities

Extending PESI-MS screening to a broader range of pharmaceuticals, toxins, and contaminants will enhance its utility. Integration with high-throughput automation, coupling with separation techniques for improved selectivity, and employing machine learning for spectral deconvolution represent key development pathways. Portable PESI-MS instruments could enable on-site testing in field and regulatory environments.

Conclusion

The PESI-MS method implemented on the DPiMS-2020 platform delivers a fast, sensitive approach for detecting sleeping pill contamination in beverages. Using both active–ingredient and excipient ion markers overcomes matrix suppression effects, offering a robust screening solution.

References

• Nakano S, Kamata H, Sasaki N et al. J Mass Spectrom Soc Jpn 2019;67(2):53–63
• Wada M et al. Application of probe electrospray ionization mass spectrometry to the analysis of poisons and drugs in adulterated foods and beverages. Jpn J Forens Sci Technol