Gold nanorods-conjugated TiO2 nanoclusters for the synergistic combination of phototherapeutic treatments of cancer cells

Abstract

BackgroundRecently, a combination of photodynamic therapy (PDT) and photothermal therapy (PTT) to generate reactive oxygen species (ROS) and heat to kill cancer cells, respectively has attracted considerable attention because it gives synergistic effects on the cancer treatment by utilizing the radiation of nontoxic low-energy photons such as long wavelength visible light and near IR (NIR) penetrating into subcutaneous region. For the effective combination of the phototherapies, various organic photosensitizer-conjugated gold nanocomplexes have been developed, but they have still some disadvantages due to photobleaching and unnecessary energy transfer of the organic photosensitizers.ResultsIn this study, we fabricated novel inorganic phototherapeutic nanocomplexes (Au NR–TiO2 NCs) by conjugating gold nanorods (Au NRs) with defective TiO2 nanoparticle clusters (d-TiO2 NP clusters) and characterized their optical and photothermal properties. They were observed to absorb a broad range of visible light and near IR (NIR) from 500 to 1000 nm, exhibiting the generation of ROS as well as the photothermal effect for the simultaneous application of PDT and PTT. The resultant combination of PDT and PTT treatments of HeLa cells incubated with the nanocomplexes caused a synergistic increase in the cell death compared to the single treatment.ConclusionThe higher efficacy of cell death by the combination of PDT and PTT treatments with the nanocomplexes is likely attributed to the increases of ROS generation from the TiO2 NCs with the aid of local surface plasma resonance (LSPR)-induced hot electrons and heat generation from Au NRs, suggesting that Au NR–TiO2 NCs are promising nanomaterials for the in vivo combinatorial phototherapy of cancer.Electronic supplementary materialThe online version of this article (10.1186/s12951-018-0432-4) contains supplementary material, which is available to authorized users.

Propolis nanoparticle enhances the potency of antimicrobial photodynamic therapy against Streptococcus mutans in a synergistic manner

“…Overall, aPDT should be taken into consideration because of their advantages, including the elimination of resistant microorganisms, few complications, improved selectivity and rapid time of action 18 . Even though locally applied aPDT avoids systemic adverse effects, high concentrations of PSs and high-energy doses of light are usually required to completely eliminate infectious bacteria 19 .…”

Development of a General Fabrication Strategy for Carbonaceous Noble Metal Nanocomposites with Photothermal Property

“…A thermocouple was used for the measurement of photothermal temperature based on previous reports [23][24][25][29][30][31]. The thermocouple measurement used Delta OHM HD2128.2 T-type.…”

“…Recent advances in the multi-functional design of GNPs allow for the generation of localized heat in the proximity of cancer tissues and additionally allow the delivery of multiple desired drugs in a controlled and targeted manner. GNPs have many benefits that make them suitable for the photothermal treatment of tumor or cancer, because they can be delivered into the local tumor area while minimizing nonspecific distribution, activated via near-infrared (NIR) laser light, creating the ability to penetrate deep into biological tissues, and modulated to create multifaceted cancer photothermal therapy [23][24][25].…”

“…The microstructure of the as-prepared nanocomposites will be characterized, and the possible formation mechanisms will be understood. The photothermal property of Au@C nanostructures, as a case study, will be examined, by referring to recent studies [23][24][25]. This study may offer a facile but effective strategy to prepare carbonaceous metal nanocomposites with potential applications in material science, catalysis, and biochemistry.…”

SERS imaging elucidates the folate receptor-mediated photothermal/photodynamic synergistic anticancer nanodrugs-induced cell apoptosis

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