THE APPLICATION OF CHITOSAN-BASED MICROPOWDERS IN DEVELOPMENT OF LATENT FINGERMARKS

Abstract

Latent fingermarks are common type of trace found on the crime scene. Therefore, their visualization and enhancement are widely used techniques in identification of offenders and accomplices by law enforcement agencies worldwide. Chemical and physical methods seemed to be reliable for that purpose and have now been used for years. Although, that kind of techniques are practical and have many advantages over other methods, unfortunately, they have a few pertinent disadvantages. Toxicity and noxiousness to human health is the biggest concern. Therefore, researchers focus their work in order to discover new methods for detection and visualization of latent fingermarks. In this regard, the usage of polymeric materials, especially biopolymers, has not yet been sufficiently tested, and scientific public is almost unaware of these materials’ potential in forensic science.

Recently, many papers have been published covering the utilization of (bio)polymers and their conjugates in forensic applications. In this paper, conjugates based on chitosan were obtained by the precipitating method and their application in detection and visualization of latent fingermarks was examined. Dissolved chitosan was crosslinked with sodium tripolyphosphate, as the crosslinking agent. The efficiency of crosslinking was confirmed by UV-Vis spectrophotometry and Fourier-transform infrared spectroscopy. The size, shape and uniformity of the obtained particles were examined using Scanning Electron and Optical Microscopy. The binding ability to fingerprints residues was confirmed by Optical Microscopy. The results of the testing demonstrated that this bio-based powder system could be potentially used as substitutes for commercially used powders in detecting and visualizing of latent fingermarks.