Boosting the tumor photothermal therapy with hollow CoSnSx-based injectable hydrogel via the sonodynamic and dual-gas therapy

Photothermal therapy (PTT) has attracted considerable attention in the field of nanomedicine owing to its high efficiency, low invasiveness , and precise controllability. However, limited by the activation of the immune system by PTT and the low penetrating ability of near-infrared lasers, the use of a single PTT is usually ineffective. Herein, a unique injectable hydrogel system was strategically designed and fabricated using CoSnS x , L-arginine, chitosan (CTS), and carboxymethyl cellulose (CMC) for sonodynamic and dual-gas therapy cooperative PTT. CoSnS x with a hollow structure can not only produce a large amount of singlet oxygen ( 1 O 2 ) under ultrasonic (US) irradiation, but also produce H 2 S gas in an acidic environment, so as to achieve sonodynamic and gas therapeutic effects. Additionally, CoSnS x exhibited excellent photothermal conversion efficiency of 48.24% under 808 nm laser irradiation. As a precursor of NO, L-arginine is incorporated into the hydrogel to enable the controlled release of NO under US/laser irradiation, thereby enhancing the PTT effect. Such a multifunctional injectable hydrogel system can achieve high therapeutic efficacy through sonodynamic and dual-gas treatment-enhanced PTT, as demonstrated by both in vitro and in vivo experiments. Our designed injectable hydrogel system provides a unique solution for enhancing the PTT.