His 6- Metal Assemblies: A Novel and Promising Drug Delivery System

Constructing an ideal drug delivery system (i.e., high drug payload, low cytotoxicity, and rapid endocytosis and lysosome escape) under mild conditions is of great interest in disease treatment, tissue engineering, bioimaging, etc. Inspired by the coordinative interactions between histidine and metal ions, we present for the first time the facile synthesis of His6-metal assemblies (HmA) particles under mild conditions. The HmA particles presented a high loading capacity, a wide variety of loadable drugs, low cytotoxicity, quick internalization and lysosomal escape and rapid intracellular drug release. In addition, HmA encapsulation greatly improved the antitumor ability of camptothecin (CPT) relative to free CPT. By capitalizing on these promising features in drug delivery, HmA should have great potential in various biomedical fields.