Enhanced Plasmon-Induced Resonance Energy Transfer (PIRET)-Mediated Photothermal and Photodynamic Therapy Guided by Photoacoustic and Magnetic Resonance Imaging

Phototherapy, including photothermal and photodynamic therapy, has attracted extensive attention due to its noninvasive nature, low toxicity, and high anticancer efficiency. The charge-separation mechanism of plasmon-induced resonance energy transfer (PIRET) has been increasingly employed to design nanotheranotic agents. Herein, we developed a novel and smart PIRET-mediated nanoplatform for enhanced, imaging-guided phototherapy. Prussian blue (PB) was incorporated into a Au@Cu2O nanostructure, which was then assembled with poly(allylamine) (PAH)-modified black phosphorus quantum dots (Au@PB@Cu2O@BPQDs/PAH nanocomposites). The hybrid nanosystem exhibited great absorption in the near-infrared region, as well as the ability to self-supply O2 by catalyzing hydrogen peroxide and convert O2 into singlet oxygen (1O2) under 650 nm laser light (0.5 W/cm2) irradiation. In vitro and in vivo assays showed that the generated heat and toxic 1O2 from Au@PB@Cu2O@BPQDs/PAH nanocomposites could effectively kill the cancer cells and suppress tumor growth. Moreover, the unique properties of the PB-modified nanosystem allowed for synergistic therapy with the aid of T1-weighed magnetic resonance imaging (T1-weighted magnetic resonance imaging) and photoacoustic imaging. This study presented a suitable way to fabricate smart PIRET-based nanosystems with enhanced photothermal therapy/photodynamic therapy efficacy and dual-modality imaging functionality. The great biocompatibility and low toxicity ensured their high potential for use in cancer therapy.