New Forensic Study Finds UV-C Imaging Can Reveal More Hidden Fingerprints on Difficult Surfaces

Researchers in the United Kingdom have found that ultraviolet-C (UV-C) imaging can significantly improve the detection of hidden fingerprints on surfaces that are difficult to examine using conventional forensic techniques.

The study, published online on October 29, 2026, in the Journal of Forensic Sciences, investigated whether combining UV-C imaging with cyanoacrylate fuming could reveal fingerprints that might otherwise remain undetected.

The research was conducted by Kimberley Jane Williamson, Daniel Rodriguez-Alvarez, Paul Deacon, and Kevin J. Farrugia.

Fingerprints are among the most frequently examined forms of physical evidence in criminal investigations. However, recovering usable ridge patterns depends heavily on the material where the fingerprint was deposited.

Some materials are classified as semi-porous because they absorb substances differently from ordinary paper or non-porous surfaces such as glass.

These surfaces can present difficulties for investigators because standard fingerprint enhancement techniques may produce weak contrast or interfere with background materials.

To investigate this problem, researchers evaluated the Full Spectrum Imaging System II (FSIS-II), examining how different imaging and chemical enhancement techniques performed on semi-porous substrates.

The experiments included controlled laboratory trials and pseudo-operational trials designed to better represent practical forensic examination conditions.

The researchers tested a sequence involving UV-C imaging, ultraviolet-A (UV-A) imaging, cyanoacrylate fuming, and black magnetic powder.

Cyanoacrylate fuming, commonly known as superglue fuming, is a fingerprint development technique in which chemical vapour reacts with fingerprint residues to form a visible polymer deposit.

The results showed that UV-C imaging before cyanoacrylate treatment was generally ineffective.

However, examining fingerprints with UV-C after cyanoacrylate fuming produced substantially better results.

In controlled laboratory trials, the technique increased fingerprint detection by up to tenfold compared with the relevant earlier examination stage.

During pseudo-operational trials, the improvement reached approximately fourfold.

Researchers attributed the improvement to increased scattering of UV-C light by the cyanoacrylate polymer, making developed fingerprint patterns easier to distinguish from surrounding surfaces.

UV-A imaging produced smaller improvements, while applying black magnetic powder after cyanoacrylate treatment did not increase the number of enhanced fingerprints in the reported experiments.

For crime scene investigators and fingerprint examiners, the findings suggest that UV-C imaging could become a useful additional examination method for certain challenging materials.

However, UV-C radiation presents health and safety concerns and may affect biological evidence intended for subsequent DNA analysis.

The researchers also emphasized that controlled and pseudo-operational results require further validation through full operational forensic laboratory trials.

The findings demonstrate how the order of fingerprint enhancement techniques can influence evidence recovery, potentially helping laboratories improve examination procedures without assuming that every surface will respond in the same way.