Single-Step Fabrication of Resonant Silicon–Gold Hybrid Nanoparticles for Efficient Optical Heating and Nanothermometry in Cells

Abstract

Heat is a well-known treatment method for a wide range of diseases. Hyperthermia treatment or intentional overheating of cells is a rapidly developing therapeutic strategy in cancer treatment. All-dielectric nanophotonics has established itself in optical applications, including nanothermometry and optical heating; generally, it involves Mie resonances in nonplasmonic nanoparticles (NPs). However, such nanomaterials do not always provide sufficient heating due to their nonoptimal size distribution after fabrication by nonlithographic approaches. To overcome this limitation, additional steps, such as size-separation of NPs, are required. Another strategy for efficient heating is intelligent integration of plasmonic and alldielectric nanostructures to develop hybrid nanomaterials with outstanding optical performances, e.g., efficient nanoheaters and nanothermometers. Taking this into account, we report on a simple and accessible approach for the fabrication of hybrid silicon−gold NPs. Their heating abilities are further compared with those of pristine monodispersed Si NPs inside and outside B16−F10 melanoma cells and confirmed by simultaneous nanoscale thermometry. The obtained results show that the obtained hybrid nanomaterials are more efficient nanoheaters even in biological environments, where cell inhomogeneity and deviations of NP sizes make it difficult to exactly meet the critical coupling conditions.

Au–Si Nanocomposites with High Near-IR Light-to-Heat Conversion Efficiency via Single-Step Reactive Laser Ablation of Porous Silicon for Theranostic Applications

“…generally explain growing popularity of this method. − Along with the mentioned benefits, the ability to create unique composite nanomaterials is undoubtedly among the most practically important modalities of the LAL technique as compared to pure chemical synthesis routes. − State-of-the-art examples of such LAL-synthesized nanocomposites include noble metal nanoalloys, − carbon-encapsulated , or van der Waals nanoparticles, , magneto-plasmonic nanomaterials (such as Au–Fe and Ag–Co NPs), as well as hybrid nanomaterials combining common semiconductors with plasmon-active materials (for example, Au­(Ag)–Si, , Au–TiO 2 , , Au–ZnO, , and so forth.). Within this research direction, during the past decade, a specific focus was made on the LAL synthesis of gold–silicon (Au–Si) nanocomposites, demonstrating an outstanding combination of linear and nonlinear optical properties. − In particular, inexpensive biocompatible nanocrystalline silicon NPs exhibit second harmonic generation and Raman yield empowerment in the case of excitation of so-called Mie resonances at pump wavelength, , which makes Si-based nanomaterials promising for diverse applications spanning from nanophotonics and optical sensing to theranostics. Merging Si with gold, a well-known chemically stable plasmon-active material, allows enhancement of near-field light localization effects mediated by excitation of localized surface plasmon resonances (LSPRs) in Au nanoclusters.…”

“…Merging Si with gold, a well-known chemically stable plasmon-active material, allows enhancement of near-field light localization effects mediated by excitation of localized surface plasmon resonances (LSPRs) in Au nanoclusters. In its turn, this boosts optical absorption and light-to-heat conversion performance of the nanoparticles, as well as allowing them to achieve broadband multiphoton photoluminescence from nanocrystalline Si via the injection of hot electrons from surrounding Au nanoinclusions. ,,− …”

Merging of Bi-Modality of Ultrafast Laser Processing: Heating of Si/Au Nanocomposite Solutions with Controlled Chemical Content

“…In particular, higher laser energy leads to the growth of larger Au NPs while the size of Si NPs decreases at similar conditions [ 28 ] that were chosen here for the fabrication of NCs. Their choice was determined by the high prospects for these elements in the fields of nanothermometry [ 29 , 30 , 31 ] and life science [ 32 , 33 , 34 , 35 ]. However, contrary to the aforementioned cases, the laser fluence variation provokes neither changes of the size of Si/Au NCs nor modifications of their chemical content [ 19 , 20 ].…”

Editorial: Special Issue “Laser Synthesis and Processing of Nanostructured Materials”

“…allows one to produce a diversity of unique nanomaterials with sophisticated structure as well as a unique chemical/phase composition defined by laser synthesis conditions and the reactivity of the surrounding liquid. Hybrid nanomaterials (nanohybrids) composed of different elements properly arranged at the nanoscale to improve the basic nanomaterial functionality are the focus of many state-of-the-art studies on PLAL [ 16 , 17 , 18 , 19 , 20 , 21 , 22 ].…”