Using NieRS for Forensic Dye Analysis

At Pittcon 2026, which took place in San Antonio, Texas, Dmitry Kurouski, an Associate Professor of Biochemistry and Biophysics, and Biomedical Engineering at Texas A&M University, delivered a talk on Sunday March 8^th titled, “Near Infrared Excitation Raman Spectroscopic Analysis of Dyes Present on Fabric.”¹ At Texas A&M University, Kurouski’s research areas include Raman-based plant disease diagnostics, forensic analysis, and developing nano-infrared spectroscopy to characterize plant waxes and amyloids.²

In his talk, Kurouski examined the use of near-infrared excitation Raman spectroscopy (NIeRS) as a non-destructive alternative to high performance liquid chromatography (HPLC) for the forensic identification of dyes in physical evidence such as hair and fabrics.¹ Dye identification can help link individuals to crime scenes. Unfortunately, traditional HPLC methods, which have been used extensively for this purpose, are destructive and time-consuming. Kurouski and his team evaluated whether NIeRS could reliably identify dyes on fabrics contaminated with body fluids, including blood, urine, and semen. Results showed that NIeRS combined with partial least-squares discriminant analysis (PLS-DA) achieved an average identification accuracy of 97.6% despite contamination.¹ The researchers also examined the effects of environmental exposure by subjecting dyed cotton fabrics to sunlight for seven weeks. Although light exposure caused gradual fading and reduced vibrational band intensities in the spectra, PLS-DA still enabled accurate dye identification throughout the exposure period.¹ These findings highlight NIeRS as a robust, non-invasive technique for forensic dye analysis.¹

Much of our conversation at Pittcon focused on his team’s forensics work. In this video clip, Kurouski explains why his team used NieRS over traditional HPLC methods to study forensic dyes, and why they concentrated their study on analyzing textiles.

Spectroscopy will be continuing to provide coverage of the Pittcon 2026 conference on an ongoing basis as we report back from San Antonio. You can stay up to date with our coverage of the Pittcon 2026 conference here.

References

1. Pittcon, Near Infrared Excitation Raman Spectroscopic Analysis of Dyes Present on Fabric. Pittcon.org. Available at: https://app.swapcard.com/event/pittcon-2026/planning/UGxhbm5pbmdfNDMxNzU3MA== (accessed 2026-03-13).
2. Texas A&M University, Dmitry Kurouski. TAMU.edu. Available at: https://bcbp.tamu.edu/people/kurouski-dmitry/ (accessed 2026-03-16).