College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
Biosens Bioelectron. 2015 Feb 15;64:345-51. doi: 10.1016/j.bios.2014.09.029. Epub 2014 Sep 18.
Herein, we have successfully built up connections between nanoparticles and nanoclusters, and further constructed a surface-enhanced fluorescence (SEF) strategy based on the two types of nanomaterials for selectively assaying carcinoembryonic antigen (CEA). Specifically, silver nanoclusters provided the original fluorescence signal, while gold nanoparticles modified with DNA served as the fluorescence enhancer simultaneously. On the basis of this proposed nano-system, the two nanomaterials were linked by CEA-aptamer, thus facilitating SEF occurring. Nevertheless, more competitive interactions between CEA and CEA-aptamer emerged once CEA added, leading to SEF failed and their fluorescence decreased. Significantly, this creative method was further applied to detect CEA, and showed the linear relationship between the fluorescence intensity and CEA concentrations in the range of 0.01-1 ng mL(-1) with a detection limit of 3 pg mL(-1) at a signal-to-noise ratio of 3, demonstrating its sensitivity and promising towards multiple applications. On the whole, this approach we established may broaden potential ways of combining nanoparticles and nanoclusters for detecting trace targets in bioanalytical fields.
在这里，我们成功地建立了纳米粒子和纳米团簇之间的联系，并进一步构建了一种基于这两种纳米材料的表面增强荧光（SEF）策略，用于选择性测定癌胚抗原（CEA）。具体来说，银纳米团簇提供了原始荧光信号，而用 DNA 修饰的金纳米粒子则同时充当荧光增强剂。在此提出的纳米系统基础上，通过 CEA-适体将这两种纳米材料连接起来，从而促进 SEF 的发生。然而，一旦加入 CEA，就会出现更多的 CEA 与 CEA-适体之间的竞争相互作用，导致 SEF 失败，其荧光强度降低。值得注意的是，这种创新方法进一步应用于检测 CEA，在 0.01-1 ng mL(-1) 的范围内，荧光强度与 CEA 浓度之间呈现线性关系，检测限为 3 pg mL(-1)，信噪比为 3，证明了其在生物分析领域检测痕量靶标方面的灵敏度和广阔的应用前景。总的来说，我们建立的这种方法可能会拓宽结合纳米粒子和纳米团簇来检测生物分析领域痕量靶标的潜在途径。
