A new visibly-excited fluorescent component in latent fingerprint residue induced by gaseous electrical discharge

A technique that exposes fingerprint residue to a gaseous electrical discha rge in nitrogen followed by treatment with ammonium hydrogen carbonate vapo rs to produce fluorescence is investigated. Particular attention is made to fluorescence observed via laser illumination at 514 nm. Insight into the n ature of the fluorescent components is achieved through the use of thin-lay er chromatography (TLC) of fingerprint residue. Results reported indicate t he fluorescence observed is from previously non-fluorescent fractions of th e fingerprint residue, and TLC results point towards lipid derivatives as a possible source of the fluorescence.