Drug testing has traditionally relied on urine, saliva, or blood samples to detect the presence of illicit substances. While these methods are well established, they often require trained personnel, specialized equipment, and a certain degree of invasiveness. In recent years, fingerprint drug testing has emerged as an innovative alternative.
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Introduction
Fingerprints, created from a deposit of sweat and sebum, contain trace chemicals that may reveal information on a person. These chemicals are related to substances an individual has ingested or come in contact with, such as skin care product residues, explosives, and drugs.
Drugs can be detected in fingerprints even after a single dose. Their concentrations vary significantly, ranging from a few picograms to nanograms, and the detection window depends on various factors such as the type of drug and duration of the treatment.
Fingerprint drug testing can, therefore, offer a noninvasive and rapid way to screen for drug use with a simplified collection process. 1
Top 5 Technologies Reshaping Forensic Science
Technology Behind It: Mass Spectrometry and Sample Collection
Drugs, and more often their metabolites, are excreted through sweat glands and can be collected from the ridges of a fingerprint using a lateral flow assay (LFA). Generally, LFAs consist of cellulose or paper-based material used to support a layer of molecules that are complementary to the analytes of interest in a sample.
The fingerprint is deposited on a collection pad, which is treated with antibodies tagged with fluorescent dyes or conjugated to gold nanoparticles. If specific drugs are present, they bind to the antibodies and become visible at the test line within minutes.
Commercial systems such as the drug screening cartridges developed by Intelligent Fingerprinting have been specifically designed for fingerprint sample collection and analysis.
Mass spectrometry is typically used for confirmatory testing. Drugs of abuse are separated from the matrix using gas or liquid chromatography and then detected using mass spectrometry (GC-MS or LC-MS, respectively).
Other techniques include matrix-assisted laser desorption/ionization (MALDI), and more recently, newer platforms have emerged that allow for high-resolution detection directly from fingerprints.
Sensitivity, Accuracy, and Use Cases
Fingerprint-based testing is a highly sensitive and time-efficient method for detecting various drugs. Most substances are detectable in sweat within two hours of use, and the window of detection typically spans several days, depending on the drug.
Drug screening cartridges based on a fluorescence-based lateral flow competition assay were successfully used for the screening of four classes of drugs - tetrahydrocannabinol (THC), cocaine, opiates, and amphetamine - in the sweat of a single fingerprint sample in less than ten minutes.
The study involving 75 participants demonstrated a detection accuracy of 93% for amphetamines and 99% for THC, with results confirmed via liquid chromatography tandem mass spectrometry (LC-MS/MS) from a second fingerprint sample.2
Unlocking the Future of Forensics
Adoption in Forensics and Healthcare
Fingerprint drug testing is widely used across a range of industries due to its accuracy, portability, and ease of use. In forensics, law enforcement agencies can deploy this method for roadside testing, post-incident screening, and correctional facility monitoring.
Sheath flow probe electrospray ionization-mass spectrometry (sfPESI-MS) uses an ambient ionization method. It has been used for the direct analysis of gel-lifted fingerprints, enabling toxicological assessment of latent prints recovered at crime scenes. Zolpidem was used as a model drug compound and was successfully detected on gel-lifted prints from glass, metal, and paper surfaces.3
Clinicians can also use fingerprint tests for routine monitoring in rehabilitation programs and outpatient care, as the method is noninvasive and less intimidating for patients.
The ease of use and portability also make it an attractive solution for industries with safety-sensitive operations, which are exploring fingerprint testing for routine screening in the workplace.4
Recent Developments
Key scientific advancements have significantly expanded the potential of fingerprint-based drug screening platforms. Mass spectrometry imaging (MSI) techniques such as desorption electrospray ionization (DESI), MALDI, and time-of-flight secondary ion mass spectrometry (ToF-SIMS) can visualize fingerprints at different pixel sizes.
MSI can be used to examine how drug compounds are distributed across fingerprint ridges and has shown potential as a suitable strategy to distinguish drug traces produced by ingestion from those derived by contact, particularly for cocaine.5
LC-MS/MS analysis of fingerprint samples collected on glass slides from a volunteer who consumed a series of drugs revealed drug use even after a single dose. Pseudoephedrine, codeine, and dextromethorphan were detected up to 24-36h after consumption, with a peak observed at 1-4 h, highlighting the importance of the approach for early intervention.1
Many ambient ionization methods have also been applied for the direct analysis of forensic traces and fingerprints. Drug traces in fingerprints down to the nanogram level have been successfully determined via direct analysis in real time (DART).
Other examples have been reported on the application of low-temperature plasma (LTP), paper spray ionization (PSI), or laser ablation direct analysis (LADI).6
The Evolution of Forensic Toxicology
Conclusion
By blending noninvasive sampling with advanced detection technologies, fingerprint drug testing delivers a fast and accurate approach for identifying drug use, with results that agree with those of other methods.
As drugs are excreted with sweat and sebum, fingerprints can be used as an alternative tool in forensic toxicology.
With the ability to differentiate ingestion from contact and the potential for real-time reporting, this method is quickly transitioning from a research innovation to a mainstream solution for forensic, clinical, and workplace settings.
References
- Adamowicz, P., Bigosińska, J., Gil, D., Suchan, M. & Tokarczyk, B. (2024). Drugs detection in fingerprints. Journal of Pharmaceutical and Biomedical Analysis, 238, 115835.https://doi.org/10.1016/j.jpba.2023.115835. Available: https://www.sciencedirect.com/science/article/pii/S0731708523006040
- Hudson, M., Stuchinskaya, T., Ramma, S., Patel, J., Sievers, C., Goetz, S., Hines, S., Menzies, E. & Russell, D. A. (2019). Drug screening using the sweat of a fingerprint: lateral flow detection of Δ9-tetrahydrocannabinol, cocaine, opiates and amphetamine. J Anal Toxicol, 43, 88-95.10.1093/jat/bky068.
- Kim, A., Kelly, P. F., Turner, M. A. & Reynolds, J. C. (2025). A direct analysis method using sheath flow probe electrospray ionisation-mass spectrometry (sfPESI-MS) to detect drug residues from fingerprint forensic gel lifts. Drug Testing and Analysis, 17, 152-162.https://doi.org/10.1002/dta.3688. Available: https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/abs/10.1002/dta.3688
- 2023. Intelligent Fingerprinting Drug Screening System Is Expected to Reduce P&O Ferries’ Overall Drug Testing Costs by 90% [Online]. Available: https://www.intelligentfingerprinting.com/insights/news/intelligent-fingerprinting-drug-screening-system-is-expected-to-reduce-po-ferries-overall-drug-testing-costs-by-90/ [Accessed 10 Apr 2025].
- Costa, C., Jang, M., De Jesus, J., Steven, R. T., Nikula, C. J., Elia, E., Bunch, J., Bellew, A. T., Watts, J. F., Hinder, S. & Bailey, M. J. (2021). Imaging mass spectrometry: a new way to distinguish dermal contact from administration of cocaine, using a single fingerprint. Analyst, 146, 4010-4021.10.1039/D1AN00232E. Available: http://dx.doi.org/10.1039/D1AN00232E
- Conway, C., Weber, M., Ferranti, A., Wolf, J.-C. & Haisch, C. (2024). Rapid desorption and analysis for illicit drugs and chemical profiling of fingerprints by SICRIT ion source. Drug Testing and Analysis, 16, 1094-1101.https://doi.org/10.1002/dta.3623. Available: https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/abs/10.1002/dta.3623
Further Reading