Forensic Science

Herein, we report the synthesis of magnetic cobalt ferrite (CFO) nanoparticles, to study its application for the development of latent fingerprints using rapid and cost-effective combustion method. X-ray diffraction (XRD) was used for the structural characterization, which confirmed the pure phase of synthesized nanoparticles. The CFO nanoparticles were used to develop latent fingerprints over a non-porous surface. The developed fingerprints were observed under a stereomicroscope and a large number of pores could be identified and differentiated as open or closed pores, and the average pore size has been calculated. All the obtained results were compared to the results obtained using commercial black magnetic latent fingerprint powder, which established the superiority of synthesized CFO nanoparticles. Current study may pave the path for the development of a potential black magnetic fingerprint powder, which can effectively reveal the fine features of latent fingerprints after development.

Fingerprints are one the most crucial evidences found at most of the crime scenes. Present article reports the synthesis of nickel cobaltite (NCO) nanoparticles using combustion method and their application for enhanced latent fingerprint (LFP) development on various surfaces. Phase purity of synthesized nanoparticles was confirmed by X-ray diffraction (XRD) studies. Synthesized NCO nanoparticles possess smaller crystallite size (~8nm). Due to this small crystallite size good clarity and fine details have been obtained in the developed fingerprints which allows to analyse up to third level classification. NCO nanoparticles were used for non-porous, semi-porous and porous surfaces to develop the latent fingerprints and have demonstrated superior fingerprint visualization and preservation. Current study also highlights the enhanced resolution of ridge characteristics and pore structure, paving the path to more accurate forensic fingerprint analysis. This paper also discussed and demonstrated that all the features of LFP are preserved in lifted fingerprints developed using NCO nanoparticle and also discussed the comparison of LFP features and characteristics developed using commercially used fingerprint powder and NCO nanoparticle. Detailed fingerprint analysis is performed using stereomicroscope of LFP developed on various surfaces for the measurement of average pore size, pore shape, pore density, density of NCO powder attached to sweat, minor details and ridge characteristics.

Semiconductor oxides are playing an important role in the advancing modern forensic science, offering sensitive, selective, and rapid analyses. At nanoscale, they have a high surface area, unique chemical and physical properties, versatility, tunable optical, electrical, and magnetic characteristics. Applying different characterization techniques with semiconductor oxides on the nano-forensic evidences can provide the accurate and efficient results. Key semiconductor oxides such as ZnO, TiO2, CuO, or Iron oxides can be used in drugs/toxic powder detection, gun powder/explosive residue analyses, fingerprint detection, and other forensic applications as photocatalysis, artificial olfactory system, powder suspension, auxiliary agent, colorimetric, gas, and electrochemical sensing.