A Facile Microwave-Assisted Green Synthetic Approach of Solid-State Fluorescent Carbon-Dot Nanopowders Derived from Biowaste for Potential Latent-Fingerprint Enhancement

Latent fingerprint detection and visualization remains a challenge especially where problems of poor contrast, auto-fluorescent surfaces and patterned backgrounds are encountered. As a result there is an increasing interest in the development of simple, cost effective, rapid and yet accurate methods for latent fingerprint detection and recovery. Herein, this paper reports the synthesis of bright blue photoluminescent carbon dots (C-dots) via an eco-friendly and simple one-step microwave-assisted carbonization of potato peels’ biomass. The C-dots were prepared in only 3 min and ground into powder and used without any further treatment. The as-prepared C-dots were characterized using atomic force microscope, Fourier transform infra-red spectroscopy and X-ray diffraction with an average size of 1.0[Formula: see text]nm. The optical properties of the as-prepared C-dots were studied by UV-Vis spectroscopy and spectrofluorometer which established an excitation and emission wavelengths of 390[Formula: see text]nm and 480[Formula: see text]nm, respectively. Owing to their strong solid state fluorescence, the as-prepared C-dots’ powder was successfully used in latent fingerprint detection and imaging on porous and nonporous surfaces. Latent fingerprints were recovered with high resolution and excellent quality providing sufficient details for individual identification. These findings demonstrate that C-dots derived from biomass have a great potential in latent fingerprint analysis for forensic applications.

Pengembangan Metode Serbuk Daun Suji (Pleomele angustifolia N.E.Br) sebagai Identifikasi Sidik Jari Laten

Fingerprint is a technology that can be used to identify a person. The dusting method is most often used on latent fingerprints because it is relatively easy and simple. However, the composition of the ingredients used in latent fingerprint powder is toxic and can be hazardous to health. This research was carried out using a new natural powder from Suji leaf as a simple, non-toxic, and cheaper. Suji leaf powder produces a green color that comes from the chlorophyll compounds contained in it. This chlorophyll compound will bind to alanine to identify latent fingerprints. The particle sizes used in this study were of 60-200 mesh. The results found that the particle sizes of 100 and 200 mesh provided good green contrast and clear visualization of the fingerprint patterns. Meanwhile, at the particle size of 60 and 80 mesh, it was found that the results were not clear visualized. The highest percentage of fingerprint patterns based on blood group, gender and ethnicity was found in form of loops. The percentage of fingerprint patterns formed based on the highest was of O 31.1; B 12.2; AB 8.8; and A 6.6 percent. The highest percentage of fingerprint patterns formed by gender were of 45.5 for women and 13.3 percent for men. The highest percentage of fingerprint patterns formed by ethnicity were Malay 21.1, Batak 20, and Javanese 17.7 percent.