Non-toxic luminescent carbon dot/poly(dimethylacrylamide) nanocomposite reagent for latent fingermark detection synthesized via surface initiated reversible addition fragmentation chain transfer polymerization

Here, non-toxic luminescent carbon nanoparticles, namely carbon dots (C-dots), were facilely synthesized via a one-pot hydrothermal route. Raman, Fourier transform infrared, fluorescence, carbon NMR and X-ray photoelectron spectroscopies revealed that the C-dots possessed a graphitic-like core with an oxidized surface. The oxidized surface of the C-dots allowed for functionalization of the C-dots with a 2-methyl-2-[(dodecylsulfanylthiocarbonyl)sulfanyl]propanoic acid chain transfer agent. Poly(N,N-dimethylacrylamide) (p(DMA)) was then grafted from the C-dot surface via surface initiated reversible addition fragmentation chain transfer (RAFT) polymerization. The resulting luminescent C-dot/polymer nanocomposite, C-dot/p(DMA), was analyzed using UV-visible and fluorescence spectrometry verifying that the functionalized surface was responsible for the C-dots' luminescence. This C-dot/p(DMA) nanocomposite was water soluble and was used as a solution for the luminescent detection of latent fingermarks deposited on non-porous aluminium foil substrates.