Aqueous green synthesis of organic/inorganic nanohybrids with an unprecedented synergistic mechanism for enhanced near-infrared photothermal performance.

Silver sulfide (AgS) nanoparticles (NPs) represent one of the most popular inorganic reagents for near-infrared (NIR) photothermal therapy (PTT). However, the extensive biomedical applications of AgS NPs are greatly compromised by the hydrophobicity of the NPs prepared in organic solvents, their low photothermal conversion efficiency, certain surface modification-induced damage to their intrinsic properties and short circulation time. To develop a facile yet efficient green approach to overcome these shortcomings for improved properties and performance of AgS NPs, we report herein the construction of AgS@polydopamine (PDA) nanohybrids a "one-pot" organic-inorganic hybridization strategy, which produces uniform AgS@PDA nanohybrids with well-modulated sizes in the range of 100-300 nm the self-polymerization of dopamine (DA) and subsequent synergistic assembly of PDA with AgS NPs in a three-phase mixed medium containing water, ethanol and trimethylbenzene (TMB). Integration of dual photothermal moieties, , AgS and PDA at a molecular level, endows AgS@PDA nanohybrids with synergistically enhanced NIR photothermal properties that are much better than those of either PDA or AgS NPs due to calculated combination indexes (CIs) of 0.3-0.7 between AgS NPs and PDA based on a modified Chou-Talalay method. Therefore, this study not only developed a facile "one-pot" green approach toward producing uniform AgS@PDA nanohybrids with well-modulated dimensions, but also revealed an unprecedented synergistic mechanism for organic/inorganic nanohybrids that is based on dual photothermal moieties providing enhanced near-infrared photothermal performance.