Stabilizing latent fingermarks developed with iodine fuming: A new method

Abstract

Efficient visualization of latent fingermarks is vital in forensic science considering variables like surface type, deposition time, and treatment method. Iodine fuming, a simple, non-destructive method, faces challenges with rapid fading of developed marks causing hindrance in documenting the developed marks. The present research introduces a novel iodine fuming procedure enhanced by a simple pre-treatment with tetra-n-butylammonium iodide (TBAI), a white powdery material, ensuring prolonged fixation of visualized marks. The method, effective across surfaces, both porous as well as non-porous stabilizes iodine fumed fingermarks via formation of tetra-n-butylammonium triiodide (TBATI), as confirmed through spectroscopic analyses with UV–Visible, Fourier-transformed infrared and Raman spectroscopy. Aged fingermarks up to 4 weeks developed on different surfaces responded positively to the method. The suggested method is non-destructive and simple to use.