Silica-Void-Gold Nanoparticles: Temporally Stable Surf ace-Enhanced Raman Scattering Substrates
Silica-Void-Gold Nanoparticles: Temporally Stable Surf ace-Enhanced Raman Scattering Substrates
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DOI：
10.1021/ja8059039
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发表时间：
2008-10-29
影响因子：
15
通讯作者：
Haes, Amanda J.
中科院分区：
文献类型：
--
作者：
Roca, Maryuri;Haes, Amanda J.
使用时间稳定的溶液相二氧化硅-空隙-金纳米颗粒和表面增强拉曼散射（Sers）证明了目标分子的可再现检测。这些复合纳米结构是均匀的（直径= 45 +/-4nm），并且将单个13 nm金纳米颗粒核捕获在多孔二氧化硅膜内，这防止了相邻纳米颗粒之间的电磁耦合和聚集。金纳米粒子的核心和复合纳米结构的结构变化的光学性质的特征在于使用消光光谱和透射电子显微镜，分别和这两种技术被用来监测二氧化硅膜的形成。所得的纳米结构表现出时间稳定的光学性质，在盐和2-萘乙撑的存在下。类似的Sers光谱特征时，观察到2-naphthalenethethethylene与裸和膜封装的金纳米粒子孵育。复合纳米粒子的中心在2566 cm（-1）处的S-H拉曼振动带消失表明目标分子直接结合到金属表面。此外，这些纳米结构表现出可再现的Sers信号至少2小时的时间。利用溶液相二氧化硅-空隙-金纳米颗粒作为可再现的Sers基底的第一次演示将允许未来的基础研究，以了解使用溶液相纳米结构的Sers机制，以及涉及生物和环境分子的直接和可再现检测的应用。
Reproducible detection of a target molecule is demonstrated using temporally stable solution-phase silica-void-gold nanoparticles and surface-enhanced Raman scattering (SERS). These composite nanostructures are homogeneous (diameter = 45 +/- 4 nm) and entrap single 13 nm gold nanoparticle cores inside porous silica membranes which prevent electromagnetic coupling and aggregation between adjacent nanoparticles. The optical properties of the gold nanoparticle cores and structural changes of the composite nanostructures are characterized using extinction spectroscopy and transmission electron microscopy, respectively, and both techniques are used to monitor the formation of the silica membrane. The resulting nanostructures exhibit temporally stable optical properties in the presence of salt and 2-naphthalenethiol. Similar SERS spectral features are observed when 2-naphthalenethiol is incubated with both bare and membrane-encapsulated gold nanoparticles. Disappearance of the S-H Raman vibrational band centered at 2566 cm(-1) with the composite nanoparticles indicates that the target molecule is binding directly to the metal surface. Furthermore, these nanostructures exhibit reproducible SERS signals for at least a 2 h period. This first demonstration of utilizing solution-phase silica-void-gold nanoparticles as reproducible SERS substrates will allow for future fundamental studies in understanding the mechanisms of SERS using solution-phase nanostructures as well as for applications that involve the direct and reproducible detection of biological and environmental molecules.