Fabrication of silver seeds and nanoparticle on core-shell Ag@SiO2 nanohybrids for combined photothermal therapy and bioimaging

In this study, two core-shell nanohybrids of different morphologies, namely SiO₂-coated silver (Ag) with surface-exposed silver seeds (Ag@SiO₂@Ag_seed) and SiO₂-coated Ag with surface-exposed Ag nanoparticles (Ag@SiO₂@Ag_NPs), were fabricated using the Stober method. Potential applications in bioimaging and photothermal therapy (PTT) of the two fabricated nanohybrids were also explored. Upon exposure to visible light (400 nm), Ag@SiO₂@Ag_seed with surface-exposed Ag seeds exhibited greater photothermal conversion efficiency than Ag@SiO₂@Ag_NPs. In vitro MTT assays in the dark and subsequent bioimaging using HeLa cells proved the potential biocompatibility of the fabricated core-shell nanohybrids. PTT applications of the two fabricated core-shell nanohybrids were studied by incubating HeLa cells with the nanohybrids, exposure to 400 nm laser, and subsequent staining with annexin V and propidium iodide (PI), and the two core-shell nanohybrids gave distinctively different PI staining results. Interestingly, Ag@SiO₂@Ag_seed caused higher cell death upon light exposure compared to Ag@SiO₂@Ag_NPs as the former generated more heat within the cells. These results demonstrated potential bioimaging and PPT applications of the fabricated core-shell nanohybrids and offer a novel candidate for phototherapy-based biomedical applications.

Photodeposition of gold nanoparticles on silica nanospheres using carbon dots as excellent electron donors

Gold nanoparticles have been photodeposited directly on SiO₂ nanospheres by using carbon dots as excellent electron donors.

A colloidal system of polythiophene-grafted edge-gold-coated silver nanoprisms with enhanced optical properties and stability

P3HT has been grafted to edge-gold-coated silver nanoprisms to have feasible-process ability, enhanced optical properties, and high stability.

A new strategy to directly construct hybrid luminescence–photothermal–magnetism multifunctional nanocomposites for cancer up-conversion imaging and photothermal therapy

Novel hybrid Ag/NaGdF₄:Yb³⁺,Er³⁺ multifunctional nanocomposites with luminescence–photothermal–magnetism properties have great promise in future up-conversion luminescence imaging and photothermal therapy of tumors.