Forensic identification of fingerprints on various substrates based on fluorescent carbon nanodots from date seeds assisted by Tracker software

• Published in: Nano-Structures & Nano-Objects 2024-09, Vol.39, p.101286, Article 101286
• Main Authors: Sesilia, Ni Kadek Nabila, Vidaroini, Saadah, Amri, Chairul, Setyawati, Fadhilah Fitria, Fikri, Muhammad Ramdhan Haikal, Dwandaru, Wipsar Sunu Brams
• Format: Article
• Language: English
• Subjects: Date seeds; Fingerprint identification; Fluorescent C-dots; Tracker software
• ISSN: 2352-507X
• DOI: 10.1016/j.nanoso.2024.101286

Fingerprint identification is done by observing fingerprint patterns usually found on various surfaces at crime scenes. However, fingerprints are easily damaged, erased, and/or lost. Therefore, alternative materials are needed that can preserve fingerprint patterns. In this study, we use carbon nanodots (C-dots). This research aims to prepare and characterize C-dots made from date seeds, and then determine the robustness of the latent fingerprints using C-dots on various printed substrates assisted by Tracker software. This is experimental research of preparing and characterizing fluorescent C-dots from date seeds and printing fingerprints on various substrates. The C-dots were prepared using oven and microwave heating methods and characterized using an ultraviolet-visible (UV-Vis) spectrophotometer, photoluminescence (PL), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and particle size analyzer (PSA). The substrates used for printing the fingerprints were plastic, ceramic, paint, and glass. Based on the characterization results, the C-dots have i) an absorption peak at wavelength of 252.2 nm (core) and band gap energy of 3.27 eV, ii) an emission wavelength of 495 nm emitting cyan color, iii) an amorphous structure based on the diffraction pattern, iv) functional groups of C-H, CC, CC, and O-H, and v) particle sizes of 1.3 nm (< 10 nm). Moreover, the results of the fingerprint identification based on the visualization test were successful because a subject’s fingerprint pattern was formed and various patterns were identified. In the robustness test, the latent fingerprints lasted 30 days and then slightly faded in the whorls pattern.