Oxygen self-enriched nanoparticles functionalized with erythrocyte membranes for long circulation and enhanced phototherapy

摘要

In recent years, indocyanine green (ICG) encapsulated in different kinds of nano-carriers have been developed to overcome its short lifetime in vivo and non-selectivity in cancer cells. However, these nanoparticles are still easily recognized and captured by the reticuloendothelial system (RES) and the low singlet oxygen quantum (0.08) of ICG inevitably leads to a limited efficacy of phototherapy. To overcome these limitations, a novel oxygen self-enriched biomimetic red blood cell (RBC) was developed by cloaking albumin nanoparticles which contained ICG and perfluorocarbon (PFC) with RBC membranes. Due to the high oxygen capacity of PFC, the oxygen self-enriched nanoparticles can enhance photodynamic therapy (PDT) by generating more singlet oxygen (O-1(2)). After successfully coated RBC membranes onto nanoparticles, the novel oxygen self-enriched biomimetic RBCs remained the characteristics of photothermal therapy (PTT) and enhanced PDT in vitro. Importantly, it can effectively reduce immune clearance in macrophage cells (RAW264.7) and significantly prolong blood circulation time, achieving high accumulation in tumor. In addition, the tumor growth was effectively inhibited after intravenous injection to tumor-bearing mice. Altogether, this oxygen self-enriched RBCs with long circulation time and high oxygen capacity as natural RBCs provide a new strategy to design biomimetic nano-system for clinical cancer phototherapy treatment.