Polyglycerol-Decorated Hollow Mesoporous Ruthenium Nanoparticles for Long Circulation and Antitumor Effect

Hollow mesoporous ruthenium nanoparticles (HMRu NPs) are especially beneficial for drug delivery and photothermal therapy due to their distinguished specific surface area and photothermal properties. However, poor circulation performance in vivo means that the NPs are subject to rapid clearance before reaching the target tissue. Polyethylene glycol (PEG) modified nanoparticles have become the classical standard to extend circulation by reducing protein adsorption and escaping macrophage phagocytosis, but PEGylation tends to have an accelerated blood clearance effect after repeated use. Considering that the hyperbranched polymers exhibit excellent performance in protein shielding, that makes it possible for them to have the potential to replace PEG. Thus, HMRu NPs were decorated by polyglycerol (PG) in this work compared to PEGylation. The antiprotein adsorption capacity and macrophage escape were assayed by the bicinchoninic acid method and confocal microscopy, suggesting that PG-coating could avoid macrophage phagocytosis more efficiently than PEGylation. Finally, the resultant HMRu-PG could be used as drug carrier for synergistic chemotherapy and photothermal therapy in tumor treatment. This work provides a promising multimodal and versatile nanocarrier in tumor therapy.