Phenylboronic acid modified carbon dots for improved protein delivery.

[Display omitted] • Amino-riched CDs were modified with 4-(bromomethyl)phenylboronic acid to prepare CD-B. • CD-B shows high affinity towards proteins with enhanced loading efficiency. • CD-B can achieve effective intracellular protein delivery. It is a great challenge to establish a universal nanocarrier for delivering different proteins, due to the differences of proteins in molecular weights, isoelectric points and spatial structures. Even though some carriers including polymer, liposomes and inorganic nanomaterials have been utilized to deliver proteins, most of them are only suitable for specific proteins. In the present work, amine-riched carbon dots (CDs) were introduced phenyl boronic acid to form CD-B, which could load various proteins with considerable contents. Hemoglobin (Hb) and glucose oxidase (GOX) were used as models to form Hb@CD-B and GOX@CD-B nanohybrids, and their loading content and efficiency were improved significantly. Most importantly, these protein hybrids could be internalized by the living cells, and the protein activities were maintained effectively. This work developed a versatile platform for efficacious loading proteins with compromising activity. [ABSTRACT FROM AUTHOR]