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.
Nanoscale. 2014 Nov 6;6(23):14360-70. doi: 10.1039/c4nr04111a.
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.
随着生物医学领域对多功能分析需求的不断增加，传统的单一诊断方法已不能满足要求。因此，新型多功能技术和材料，用于整合样本采集、传感和成像，需求巨大。核壳纳米粒子为在单个粒子中结合多种功能提供了独特的平台。在这项工作中，我们构建了一种新型核壳超顺磁纳米壳（Fe₃O₄@SiO₂@Au），由 Fe₃O₄ 簇核、薄的 Au 壳和中间的 SiO₂ 层组成。所获得的多功能纳米粒子有效地结合了磁性和等离子体光学性质，通过多种实验表征方法和理论模拟进行了深入研究。我们已经证明，Fe₃O₄@SiO₂@Au 纳米粒子可用于双光子荧光（TPL）成像、近红外表面增强拉曼散射（NIR SERS）和通过磁分离进行细胞收集。通过外部磁场触发的自组装纳米粒子链中的等离子体耦合效应，可进一步大大增强 TPL 强度。此外，Fe₃O₄@SiO₂@Au 纳米粒子在磁共振成像（MRI）和光热疗等方面可能具有巨大的应用潜力。在单个纳米粒子中成功结合多种功能，包括磁响应、生物传感和生物成像，允许对活细胞进行进一步操作、实时跟踪和细胞内分子分析，达到单细胞水平。
