Photothermal-Actuated Thermoelectric Therapy by Harnessing Janus-Structured Ag–Ag<sub>2</sub>S Nanoparticles with Enhanced Antitumor Efficacy
Pengyu Zang, Yaqian Du, Chenghao Yu, Dan Yang, Shili Gai, Lili Feng, Shikai Liu, Piaoping Yang, Jun Lin
Abstract
The newly developed thermoelectric dynamic therapy (TEDT) may not only solve the problem that photothermal therapy (PTT) is limited by the overexpression of heat shock proteins (HSPs) in tumor cells but also improve the killing effect through a dynamic process. Here, we propose photothermal-driven TEDT based on Ag–Ag 2 S nanoparticles that integrate Ag 2 S with Ag + vacancies (V Ag ) and Ag in a Janus structure. V Ag and Ag optimize the band structure and thermoelectric properties of Ag 2 S, and additional electrons from the introduction of Ag enhance the PTT effect and facilitates the construction of a significant thermoelectric field for electron–hole migration in the reverse direction, thereby markedly enhancing the TEDT effect. Furthermore, the generated V Ag can also serve as a hole trap to suppress electron–hole recombination to promote 1 O 2 production, which inactivates HSPs to produce positive feedback on PTT, leading to better antitumor efficacy. The combined photothermal–thermoelectric therapeutic properties of Ag–Ag 2 S were verified from both in vivo and in vitro perspectives using ESR, UV–visible spectroscopy, cellular experiments, simulated tumor models, and other experiments.