Enhancing the visualization of latent fingerprints by aggregation induced emission of siloles

Aggregation-induced emission of two silole compounds was explored for enhancing the visualization of latent fingerprints on wet non-porous surfaces. This effect was proved to stem from the hydrophobic interaction between silole aggregates and fingerprint residues. Fingerprints are the impressions le. by raised portions of the friction skin, which feature a series of lines corresponding to ridges and grooves. It is the pattern of these ridges and grooves that renders each fingerprint unique. Since the late 19th century, fingerprints have been used in forensic investigations to establish the identity of an individual, and continue to be an important tool in our daily life for many other purposes, such as access control, safety inspection, and individual credentials.(1,2) The most common form of fingerprint evidence is latent finngerprints (LFPs), which are present but invisible to the naked eye and require some means of development to enhance the visual contrast between the prints and their backgrounds. The past two decades have witnessed great innovation of the instrumental and synthetic techniques successfully employed for fingerprint detection. For example, chemical imaging techniques utilizing Raman,(4,5) FTIR,(6-8) and mass spectrometry,(9-11) have significantly improved the study of. ngerprint composition because of their ability to identify and map the compounds present in fingerprint residues. Additionally, the application of nanoparticles (NPs), including gold NPs,(11-15) TiO2 particles,(16) nano-structured ZnO,(17) and quantum dots,(18,19) for fingerprint detection has also attracted considerable interest.