Self-assembled composite microparticles with surface protrudent porphyrin nanoparticles enhance cellular uptake and photodynamic therapy

Abstract

The surface topology of nano/microparticles plays a significant role in modulating their interactions with cells, and may serve as a robust strategy for promoting cellular delivery. However, it is still an on-going challenge to achieve enhanced cellular delivery using surface-engineered organic-based particles. Herein, novel porphyrin micro–nanocomposite particles (MP–NPs), with poly(allylamine hydrochloride)-g-porphyrin MPs (PAH-g-Por MPs) as the core and porphyrin NPs as the protrudent structures on the surface, were prepared through a pH-responsive partial decomposition-induced self-assembly method. The porphyrin domains were less aggregated and easily exposed to cells, leading to significantly enhanced cellular uptake, stronger generation of intracellular reactive oxygen species (ROS), and a more effective photodynamic therapy effect compared with their smooth counterpart microparticles (MPs). The novel concept of turning therapeutics into biomimetic nanomaterials for enhanced cellular delivery and therapy may provide an inspiring horizon for the design of photosensitizers or other therapeutic delivery systems.