Biodegradable black phosphorus-based nanospheres for in vivo photothermal cancer therapy

TLDR

Photothermal therapy is highly efficient and minimally invasive, yet its clinical use is limited by concerns over the biodegradability and long‑term toxicity of nanoagents. The authors fabricated biodegradable BPQDs/PLGA nanospheres by emulsifying PLGA loaded with black‑phosphorus quantum dots, which shields the BPQDs from oxygen and water, improves photothermal stability, and regulates their degradation rate. In vitro and in vivo studies show the nanospheres exhibit negligible toxicity, excellent biocompatibility, and potent photothermal tumor ablation under near‑infrared laser, indicating strong clinical promise.

Abstract

Photothermal therapy (PTT) offers many advantages such as high efficiency and minimal invasiveness, but clinical adoption of PTT nanoagents have been stifled by unresolved concerns such as the biodegradability as well as long-term toxicity. Herein, poly (lactic-co-glycolic acid) (PLGA) loaded with black phosphorus quantum dots (BPQDs) is processed by an emulsion method to produce biodegradable BPQDs/PLGA nanospheres. The hydrophobic PLGA not only isolates the interior BPQDs from oxygen and water to enhance the photothermal stability, but also control the degradation rate of the BPQDs. The in vitro and in vivo experiments demonstrate that the BPQDs/PLGA nanospheres have inappreciable toxicity and good biocompatibility, and possess excellent PTT efficiency and tumour targeting ability as evidenced by highly efficient tumour ablation under near infrared (NIR) laser illumination. These BP-based nanospheres combine biodegradability and biocompatibility with high PTT efficiency, thus promising high clinical potential.