NIR-Triggered Theranostic Bi2S3 Light Transducer for On-Demand NO Release and Synergistic Gas/Photothermal Combination Therapy of Tumors

Gaseous therapy based on nitric oxide (NO) has emerged as a potential tumor therapy route. However, the development of a NO generator with precisely controlled NO releasing in the target site is still facing enormous challenges. Herein, a typical NO delivery platform by integrating the hollow structured polydopamine (PDA) coated Bi2S3 nanohybrids (denoted as H-Bi2S3@PDA) with a heat-sensitive S-nitrosothiol (RSNO) molecule was explored for near-infrared (NIR) light-responsive on-demand NO-releasing and synergetic gas/photothermal combination therapy of tumors. The designed H-Bi2S3@PDA nanocomposites hold high photothermal conversion efficiency of 46.13% under irradiation of a NIR laser, leading to NIR light-triggered controllable generation of NO gas via breaking the S-NO bonds of the heat-sensitive RSNO molecules. More importantly, synergistic gas/photothermal therapy of the tumor was also achieved, which presented remarkable inhibition growth and ablation of tumors. These findings provide the opportunity to design a NIR light-activated NO generator with a combination of photothermal materials and heat-sensitive molecules for integrative gas/photothermal therapy in deep tumors.