Multi-Purpose Fluorescent Powder: Development of Latent Fingerprints and Glove Prints

A novel hydroxy benzothiazole based yellow fluorescent powder (labelled as 2-SiO2) was prepared by adsorption of 2 on silica (4 % w/w) for visualization of latent fingerprints (LFPs) and glove prints using powder dusting method. The solid-state spectrum of 2-SiO2 shows emission peak at 550 nm with CIE-1931 coordinates ( x,y ${x,y}$ ) of 0.42, 0.50 and yellow colour purity is 58.6 %. The high fluorescence of 2 in the solid-state could be attributed to AIE+ESIPT features. Due to high fluorescence (phi=0.422) ${(\varphi{} =0.422)}$ of 2-SiO2 (4 % w/w) powder, fluorescence imaging of LFPs on a variety of porous and non-porous substrates including glove prints, up to levels 1-3, without any post-treatment has been achieved. The 2-SiO2 showed strong interaction with D-Glucose, urea and lactate components present in sweat. The practical applications of 2-SiO2 powder have been demonstrated by analysis of LFPs, development of LFPs at different temperatures; aged, stained fingerprints and preservation of developed fingerprints for documentation purposes. Fluorescent powder for visualization of (stained, aged) latent finger, glove prints using powder dusting method and their applications including analysis and preservation of developed fingerprints for documentation purposes is reported. image