Phytic acid-modified manganese dioxide nanoparticles oligomer for magnetic resonance imaging and targeting therapy of osteosarcoma

Abstract

Osteosarcoma is the most common malignant tumor in the skeletal system with high mortality. Phytic acid (PA) is a natural compound extracted from plant seeds, which shows certain antitumor activity and good bone targeting ability. To develop a novel theranostics for magnetic resonance imaging (MRI) and targeting therapy of osteosarcoma, we employed PA to modify manganese dioxide nanoparticles (MnO2@PA NPs) for osteosarcoma treatment. The MnO2 NPs oligomer was formed by PA modification with uniformed size distribution and negative zeta potential. Fourier-transform infrared spectroscopy, X-ray diffraction, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis demonstrated that PA has been successfully modified on MnO2 NPs, and the structure of MnO2@PA NPs is amorphous. In vitro experiments demonstrated that MnO2@PA NPs oligomer can be efficiently internalized by tumor cell, and the internalized NPs can react with H2O2 under acid microenvironment to produce Mn2+ and O2. In vivo experiments demonstrated that MnO2@PA NPs oligomer can passively accumulate in tumor tissue, and the accumulated NPs can produce Mn2+ and O2 for MRI and targeting therapy of osteosarcoma. In conclusion, we prepared a novel bone-targeting nano theranostics for MRI and therapy of osteosarcoma.