SERS enhancement of gold nanospheres of defined size
SERS enhancement of gold nanospheres of defined size
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DOI：
10.1002/jrs.2939
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发表时间：
2011-09-01
影响因子：
2.5
通讯作者：
Kneipp, Janina
中科院分区：
文献类型：
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作者：
Joseph, Virginia;Matschulat, Andrea;Kneipp, Janina
单分散，柠檬酸盐稳定的金纳米粒子的尺寸范围从15至40 nm的合成和其特征在于，通过小角X射线散射和紫外-可见实验。相同的表面性质的不同尺寸的纳米粒子，以避免化学表面增强的拉曼散射（Sers）增强的变化，以及选择的实验条件，使没有发生聚集，使调查的增强个别纳米球。用染料结晶紫测定Sers的增强因子。单个金纳米球的EF范围为10（2）至10（3），与理论预测一致。单个球体的EF随尺寸的增加可以与纳米颗粒溶液的消光光谱的变化相关。这证实了随着尺寸的增加增强的增加是由于电磁增强的增加。除了这种独立的金球的EF对它们的大小的依赖性，EF被证明是随着分析物浓度的分析物诱导的聚集的结果而变化。这对纳米颗粒溶液作为Sers基底在定量分析任务中的应用具有影响。版权所有（C）2011约翰威利父子有限公司
Monodisperse, citrate-stabilized gold nanoparticles of sizes ranging from 15 to 40 nm were synthesized and characterized by small angle X-ray scattering and UV-vis experiments. Identical surface properties of nanoparticles of different sizes to avoid variation in the chemical surface-enhanced Raman scattering (SERS) enhancement, as well as selection of experimental conditions so that no aggregation took place, enabled the investigation of enhancement of individual nanospheres. Enhancement factors (EFs) for SERS were determined using the dye crystal violet (CV). EFs for individual gold nanospheres ranged from 10(2) to 10(3), in agreement with theoretical predictions. An increase of the EFs of individual spheres with size can be correlated to changes in the extinction spectra of nanoparticle solutions. This confirms that the increase in enhancement with increasing size results from an increase in electromagnetic enhancement. Beyond this dependence of EFs of isolated gold spheres on their size, EFs were shown to vary with analyte concentration as a result of analyte-induced aggregation. This has implications for the application of nanoparticle solutions as SERS substrates in quantitative analytical tasks. Copyright (C) 2011 John Wiley & Sons, Ltd.