Nanomaterials (Basel, Switzerland)

2079-49911132021Feb26Nanomaterials (Basel, Switzerland)Nanomaterials (Basel)Laser Ablation-Assisted Synthesis of Plasmonic Si@Au Core-Satellite Nanocomposites for Biomedical Applications.59210.3390/nano11030592Owing to strong plasmonic absorption and excellent biocompatibility, gold nanostructures are among best candidates for photoacoustic bioimaging and photothermal therapy, but such applications require ultrapure Au-based nanoformulations of complex geometry (core-shells, nanorods) in order to shift the absorption band toward the region of relative tissue transparency (650-1000 nm). Here, we present a methodology for the fabrication of Si@Au core-satellite nanostructures, comprising of a Si core covered with small Au nanoparticles (NP), based on laser ablative synthesis of Si and Au NPs in water/ethanol solutions, followed by a chemical modification of the Si NPs by 3-aminopropyltrimethoxysilane (APTMS) and their subsequent decoration by the Au NPs. We show that the formed core-satellites have a red-shifted plasmonic absorption feature compared to that of pure Au NPs (520 nm), with the position of the peak depending on APTMS amount, water-ethanol solvent percentage and Si-Au volume ratio. As an example, even relatively small 40-nm core-satellites (34 nm Si core + 4 nm Au shell) provided a much red shifted peak centered around 610 nm and having a large tail over 700 nm. The generation of the plasmonic peak is confirmed by modeling of Si@Au core-shells of relevant parameters via Mie theory. Being relatively small and exempt of any toxic impurity due to ultraclean laser synthesis, the Si@Au core-satellites promise a major advancement of imaging and phototherapy modalities based on plasmonic properties of nanomaterials.Al-KattanAhmedA0000-0003-2454-8436Aix-Marseille University, CNRS, LP3, Campus de Luminy, 13013 Marseille, France.TselikovGlebGAix-Marseille University, CNRS, LP3, Campus de Luminy, 13013 Marseille, France.Moscow Institute of Physics and Technology, Center for Photonics and 2D Materials, 141700 Dolgoprudny, Russia.MetwallyKhaledKAix-Marseille University, CNRS, LMA, 13013 Marseille, France.Aix-Marseille University, CNRS, Institut Fresnel, Centrale Marseille, 13013 Marseille, France.PopovAnton AAA0000-0001-8902-0371Aix-Marseille University, CNRS, LP3, Campus de Luminy, 13013 Marseille, France.MEPhI, Bio-Nanophotonics Laboratory, Institute of Engineering Physics for Biomedicine (PhysBio), 31 Kashirskoe sh., 115409 Moscow, Russia.MensahSergeSAix-Marseille University, CNRS, LMA, 13013 Marseille, France.KabashinAndrei VAV0000-0003-1549-7198Aix-Marseille University, CNRS, LP3, Campus de Luminy, 13013 Marseille, France.MEPhI, Bio-Nanophotonics Laboratory, Institute of Engineering Physics for Biomedicine (PhysBio), 31 Kashirskoe sh., 115409 Moscow, Russia.engGravity projectITMO Aviesan "National Alliance for the Life Sciences & Health"19-72-30012Russian Science FoundationJournal Article20210226