A novel light-induced ATRP for the preparation of water dispersible fluorescent nanodiamonds and their biological imaging applications

Carbon-based fluorescent nanoparticles are considered to be new promising nontoxic fluorescence probes which suitable for various bioimaging and biomedical applications. However, the synthesis and production of such high-quality fluorescent carbon-based nanoparticles is still challenging, and its most application potential is unexplored. In this work, we introduce a facile light-induced surface-initiated atomic transfer radical polymerization (SI-ATRP) method to fabricate the nanodiamonds (NDs) based fluorescence probes in the absence of transition metal ligands. In this sample way, the Fluorescein was employed and played the role as the fluorescent signal and photocatalyst simultaneously for its photochemical property. Besides, the poor dispersibility of pristine NDs was also obviously improved by modifying with PEGMA, and the modified NDs (FNDs-polyPEGMA) display good dispersion and biocompatibility via characterization methods. A series of characterization techniques were also carried out to confirm the successful fabrication of fluorescent NDs after polymerization. Through our investigation, the as prepared FNDs-polyPEGMA nanoparticles with high dispersibility and stable green fluorescence could be the potentially used fluorescent probes in biomedical application.