Self-Assembled Aza-BODIPY and Iron(III) Nanoparticles for Photothermal-Enhanced Chemodynamic Therapy in the NIR-II Window

Abstract

Despite its promising potential in cancer treatment, synergistic photothermal/chemodynamic therapy remains underdeveloped with regard to the utilization of metal-organic materials under second near-infrared (NIR-II) laser excitation. Herein, we report a three-dimensional network constructed via the metal coordination between catechol-functionalized aza-boron dipyrromethenes and iron ions (<b>ABFe</b>), which was further encapsulated by F127 to obtain <b>ABFe</b> nanoparticles (NPs) for combined photothermal/chemodynamic therapy. <b>ABFe</b> NPs exhibited intense absorption in the NIR-II range and negligible fluorescence. Upon 1064 nm laser irradiation, <b>ABFe</b> NPs showed high photothermal conversion efficiency (PCE = 55.0%) and excellent photothermal stability. The results of electron spin resonance spectra and <i>o</i>-phenylenediamine chromaticity spectrophotometry proved that <b>ABFe</b> NPs were capable of generating harmful reactive oxygen species from hydrogen peroxide for chemodynamic therapy, which was promoted by photothermal performance. Notably, <i>in vitro</i> and <i>in vivo</i> experiments demonstrated the great potential of <b>ABFe</b> NPs in photoacoustic imaging and photothermal-enhanced chemodynamic therapy under NIR-II laser irradiation. Therefore, the current work presents a prospective NIR-II excitation therapeutic nanomedicine for combination therapy, offering a novel strategy for simultaneously achieving extended NIR absorption of aza-BODIPY and enhanced chemodynamic therapy with metal-organic materials.