Biocompatible Heat-Shock Protein Inhibitor-Delivered Flowerlike Short-Wave Infrared Nanoprobe for Mild Temperature-Driven Highly Efficient Tumor Ablation.

Multifunctional nanomaterials for dual-mode imaging guided cancer therapy are highly desirable in clinical applications. Herein, a flowerlike NiS2-coated NaLuF4:Nd (Lu:Nd@NiS2) nanoparticle was synthesized as a novel therapeutic agent for short-wave infrared light imaging and magnetic resonance imaging to guide photothermal therapy (PTT). The material was then loaded with phenolic epigallocatechin 3-gallate (EGCG), which is a natural heat-shock protein 90 (HSP90) inhibitor. Upon near infrared irradiation, EGCG was released from the Lu:Nd@NiS2-EGCG, which bound HSP90 and reduced cell tolerance to heat, resulting in a better therapeutic effect at the same elevated temperature. Therefore, with minimal side effects and remarkable antitumor efficacy in vivo, Lu:Nd@NiS2-EGCG appeared to be a promising photothermal agent for enhanced PTT.