Mechanosynthesis of fluorescent magnetic alumina for latent fingerprint detection.

A green approach towards the synthesis of both conventional and magnetic fluorescent powders for revealing latent fingerprints (FPs) is disclosed. The powders formulation is based on a biodegradable matrix and fluorescent dyes extracted from commercial felt-tip markers. Two classes of powders are described: one with a fluorescent component, and other with both fluorescent and magnetic components. The incorporation of the magnetic component not only enables easy manipulation but also eliminates the risk of latent print ridge destruction. Optimization of the mechanosynthesis parameters allowed the development of magnetic powders with intense fluorescence emission, avoiding quenching caused by the magnetic component. The new powders proved to be highly efficient in revealing latent FPs on a variety of surfaces of forensic interests. The efficacy of these powders was demonstrated by comparison with commercial fluorescent magnetic and non-magnetic powders. The novel powders, prepared using a green protocol and biodegradable matrices, display excellent fluorescence properties, are cost-effective, easy to manipulate, and offer a significant advancement in fingerprint detection.