Discovery and Labeling Applications of a Novel Aggregation-Induced Emission Compound as a Byproduct of Hydrothermal Carbon Nanoparticle Synthesis

Carbon dots are a relatively new class of carbonaceous nanoparticles exhibiting unique and desirable features including excitation dependent emission and often good biocompatibility. Generally, the most facile route of synthesis is through the hydrothermal treatment of carbon precursors, leading to the desired nanoparticles as well as a large volume of byproducts, often exhibiting fluorescence as well. These byproducts are generally discarded, but may present their own unique and useful applications as well. In this work, we isolated one byproduct of a Carbon dot synthesis which exhibited relatively uncommon aggregation-induced emission (AIE) activity. Further characterization revealed that the mechanism of AIE in this molecule is even less common, likely relating to the formation of nanocrystals or other ordered self-assemblies rather than through restriction of intramolecular forces as in conventional AIE exhibiting molecules. Finally, we demonstrate the potential to use this molecule for labeling of both biological membranes as well as for anti-counterfeiting purposes.