Synthesis of magnesium nanoparticle for NIR-II-photoacoustic-imaging-guided synergistic burst-like and H2 cancer therapy

Summary

Metallic magnesium is a promising platform for H₂ cancer therapy, whereas the available Mg particles' undesirable diameter and shape greatly hinder its therapeutic application. Herein, we first reported the diameter- and shape-controlled synthesis of Mg nanoparticles, including hexagonal nanosheet (∼80–320 nm), nanoflower (∼100–250 nm), and small nanoparticle (mean 65 nm), by a one-pot method. As a proof of concept, pH-sensitive polymer-coated Mg nanoflowers were prepared and applied in NIR (near infrared)-II photoacoustic and bubble-enhanced ultrasound imaging and cancer therapy. It continuously generated H₂ in the tumor because the acidic tumor environment triggered the disassembly of the polymeric shell, leading to the reaction of Mg and water. The generated H₂ bubbles not only induced transient cavitation and mechanically ruptured lysosomes but also disturbed the cellular energy metabolism and induced high oxidative stress simultaneously, leading to cancer-cell death. Thus, this drug-free therapy method presented superior synergistic tumor inhibition effects.