Polydopamine Nanoparticles for Deep Brain Ablation via Near-infrared Irradiation

Local resection or ablation remains an important approach to treat drug-resistant central neurological disease. Conventional surgical approaches are designed to resect the diseased tissues. The emergence of photothermal therapy (PTT) offers a minimally-invasive alternative. However, their poor penetration and potential off-target effect limit their clinical application. Here, polydopamine nanoparticles (PDA-NPs) were prepared and characterized. Studies were performed to evaluate whether PDA-NPs combined with near-infrared (NIR) light can be used to ablate deep brain structures in vitro and in vivo. PDA-NPs were prepared with a mean diameter of ~150 nm. The particles show excellent photothermal conversion efficiency. PDA-NPs did not show remarkable cytotoxicity against neuronal-like SH-SY5Y cell lines. However, it can cause significant cell death when combined with NIR irradiation. Transcranial NIR irradiation after PDA-NPs administration induced enhanced local hyperthermia as compared with NIR alone. Loca...