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Predicting Fingerprint Age Based on Ozonolysis Kinetics of Unsaturated Triacylglycerol Degradation

NCJ Number
Analytical Chemistry Volume: 95 Issue: 32 Dated: 2023 Pages: 12047-12053
Date Published
7 pages

This study explores the possibility of predicting fingerprint age based on the chemical kinetics associated with the ambient ozonolysis of unsaturated triacylglycerols (TGs), a major component in fingerprint lipids.


In this study, the authors attempt to determine the time since deposition (TSD) of aged fingerprints from the chemical profile captured within a matrix-assisted laser desorption/ionization mass spectrometry data set. The overall decay of unsaturated triacylglycerols (TGs) follows the pseudo-first-order reaction kinetics, validating the researchers’ hypothesis; however, there are significant person-to-person variations in the initial abundance of unsaturated TGs and the decay rate, hampering the accurate prediction of TSD unless they are corrected for each individual. Nevertheless, the model’s applicability for ambient fingerprint aging data was successfully demonstrated. Despite several decades of studies to find an empirical correlation in fingerprint aging, there has been no reliable method so far. This study’s approach is based on the chemical kinetics associated with the ambient ozonolysis of unsaturated TGs, a major component in fingerprint lipids. First, ozone concentration and ambient temperature were determined to be the major factors in the degradation of unsaturated TGs. A simple kinetics model is then developed to describe the decay of unsaturated TGs, dictated only by the temperature and ozone concentration. This model is then applied to the degradation of TGs in a mixture of TG standards and multiple individuals’ fingerprints. (Published Abstract Provided)

Date Published: January 1, 2023