title: Multifunctional superparamagnetic nanoshells: combining two-photon luminescence imaging, surface-enhanced Raman scattering and magnetic separation.
abstract: With the increasing need for multi-purpose analysis in the biomedical field, traditional single diagnosis methods cannot meet the requirements. Therefore new multifunctional technologies and materials for the integration of sample collection, sensing and imaging are in great demand. Core-shell nanoparticles offer a unique platform to combine multifunctions in a single particle. In this work, we have constructed a novel type of core-shell superparamagnetic nanoshell (Fe₃O₄@SiO₂@Au), composed of a Fe₃O₄ cluster core, a thin Au shell and a SiO₂ layer in between. The obtained multifunctional nanoparticles combine the magnetic properties and plasmonic optical properties effectively, which were well investigated by a number of experimental characterization methods and theoretical simulations. We have demonstrated that Fe₃O₄@SiO₂@Au nanoparticles can be utilized for two-photon luminescence (TPL) imaging, near-infrared surface-enhanced Raman scattering (NIR SERS) and cell collection by magnetic separation. The TPL intensity could be further greatly enhanced through the plasmon coupling effect in the self-assembled nanoparticle chains, which were triggered by an external magnetic field. In addition, Fe₃O₄@SiO₂@Au nanoparticles may have great potential applications such as enhanced magnetic resonance imaging (MRI) and photo-thermotherapy. Successful combination of multifunctions including magnetic response, biosensing and bioimaging in single nanoparticles allows further manipulation, real-time tracking, and intracellular molecule analysis of live cells at a single-cell level.
authors.affiliation: Shanghai Engineering Research Center of Medical Device and Technology at Med-X, School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China. yejian78@sjtu.edu.cn.
authors.forename: Xiulong
authors.initials: X
authors.lastname: Jin
authors.forename: Haiyan
authors.initials: H
authors.lastname: Li
authors.forename: Shanshan
authors.initials: S
authors.lastname: Wang
authors.forename: Ni
authors.initials: N
authors.lastname: Kong
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
authors.forename: Qihua
authors.initials: Q
authors.lastname: Fu
authors.forename: Hongchen
authors.initials: H
authors.lastname: Gu
authors.forename: Jian
authors.initials: J
authors.lastname: Ye
mesh_terms: D052203:Ferrosoferric Oxide / Q000737:chemistry / Q000494:pharmacology; D006046:Gold / Q000737:chemistry / Q000494:pharmacology; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D049449:Luminescence; D008279:Magnetic Resonance Imaging / Q000379:methods; D057145:Nanoshells / Q000737:chemistry*; D061848:Optical Imaging / Q000379:methods*; D012822:Silicon Dioxide / Q000737:chemistry / Q000494:pharmacology
chemical_list: D006046:Gold; D012822:Silicon Dioxide; D052203:Ferrosoferric Oxide