Supramolecular Hybrids of AIEgen with Carbon Dots for Noninvasive Long-Term Bioimaging

Fluorescent bioprobes have been regarded as promising tools for bioimaging in recent years due to their excellent properties. However, the aggregation-caused quenching of emissions is a big limitation in practice for this strategy. Organic dyes with aggregation-induced emission (AIE) feature can effectively solve this problem. Herein, stable fluorescent nanoparticles were prepared by supramolecular assembling of carbon dots (CDs) and hydrophobic AIEgen. The formulated CDsG-AIE 1 exhibits superior physical and photo stability than AIE self-assembling nanoparticles in various physiology conditions. On the other hand, the formulated CDsG-AIE 1 also showed advanced features such as large Stokes shift, good biocompatibility, high emission efficiency, and strong photobleaching resistance. More importantly, the CDsG-AIE 1 can be readily internalized by HeLa cells, and strong red fluorescence from the nanoparticles can still be clearly observed after six generations over 15 days. In addition, the CDsG-AIE 1 also exhibits superior long-term imaging ability in vivo. These incredible features make the AIE nanoparticles to be an ideal fluorescent probe for noninvasive long-term tracing and imaging applications. This work highlights the potential of using carbon dots to assemble AIEgen for the preparation of nanoscale AIEgen-contained particles for desirable bioimaging and diagnostic.