CdS/polymer nanocomposites synthesized via surface initiated RAFT polymerization for the fluorescent detection of latent fingermarks.

Current advances in nanoscience have provided the unique opportunity to utilize nanostructured materials to improve the visualization and quality of fingermark development. Here, we show the facile controlled fabrication of CdS/poly(dimethylacrylamide), CdS/poly(dimethylacrylamide-co-methyl methacrylate) and CdS/poly(dimethylacrylamide-co-styrene) fluorescent quantum dot nanocomposites for use as latent fingermark developing agents on non-porous surfaces. First, CdS quantum dots were capped with 2-mercaptoethanol with subsequent immobilization of a carboxylated C12-chain transfer agent (C12CTA) via an ester bond. A surface initiated reversible addition fragmentation chain transfer (RAFT) polymerization was then performed under a controlled system resulting in nanocomposites containing polymers of low polydispersity. The intrinsic optical properties of the CdS quantum dots were retained throughout the synthetic pathways, which allowed for the successful one-step application and fluorescent visualization of latent fingermarks (fresh and aged) on aluminum foil and glass substrates under UV illumination.