A study on human serum albumin corona formed on photoluminescent carbon dots

Fluorescence nanostructures have been widely applied in the biomedical field as therapeutic agents and as novel tools for labeling, imaging, and sensing. However, the protein corona will dramatically influence the predesigned properties of nanostructures in serum. Therefore, it is important to understand the mechanism of protein corona formation on nanostructures. Photoluminescent carbon dots have been widely applied in the biomedical field since their discovery. Due to the large overlap between the absorption spectra of proteins and the fluorescence spectra of photoluminescent carbon dots, herein we investigate the mechanism of human serum albumin corona formed on photoluminescent carbon dots using fluorescence resonance energy transfer. By employing spectroscopic methods, the binding constants and the number of binding sites between human serum albumin and photoluminescent carbon dots have been determined, and the corresponding thermodynamics are also discussed as well for the interaction between photoluminescent carbon dots and human serum albumin. In addition, we successfully demonstrate the photoluminescent carbon dots in labeling bean sprouts. We believe that the current research cannot shed light on the mechanism of protein corona formation on nanostructures, but also could benefit the design of hybrid nanomaterial which will be applied to serum environments.