Ultrafast laser synthesis of NIR-absorbing Au-TiO2 nanoagents for photothermal theranostics

Amosov A., Stanislav O. Gurbatov, Aleksandr V. Shevlyagin, Andrei Pilnik, Evgeny Modin, Soslan Khubezhov, Ekaterina S. Menchinskaya, Tatiana Yu. Gorpenchenko, Dmitry L. Aminin, Aleksandr A. Kuchmizhak

Colloids and Surfaces B: Biointerfaces 2026; 259: 115359

ure noble metal nanoparticles (NPs) are widely used as benchmarks in theranostic applications, such as photothermal cancer therapy. However, plasmon-mediated absorption of such NPs is typically confined to the visible range, resulting in poor light-to-heat conversion efficiency within the near-infrared (NIR) wavelengths matching biological transparency windows. Here, we report a rapid, single-step synthesis of NIR-absorbing Au-TiO2 nanocomposites through femtosecond-laser modification of a commercial anatase TiO2 nanopowder (P25) suspension containing tetrachloroauric acid. High-repetition-rate ultrashort laser irradiation yields, within minutes, core-satellite nanostructures (<100 nm) comprising an amorphous titania core decorated with Au nanoclusters. Comprehensive characterization confirms laser-induced modifications, which endow the product with strong NIR absorption in the first biological transparency window. Au-TiO2 NPs exhibit a competitive photothermal conversion efficiency at low concentrations down to 10 μg/mL, low in vitro toxicity comparable to pristine P25 TiO2 NPs, and efficient uptake by triple-negative breast cancer cells. Additionally, the nanocomposites demonstrate a drug-carrying capacity and compatibility with bio-visualizing molecules, highlighting their potential as a novel nanoagent for anticancer theranostics.

DOI 10.1016/j.colsurfb.2025.115359