Silver nanoparticle enhanced immunoassays: one step real time kinetic assay for insulin in serum
Silver nanoparticle enhanced immunoassays: one step real time kinetic assay for insulin in serum
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DOI：
10.1016/s0939-6411(03)00115-2
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发表时间：
2003-11-01
影响因子：
4.9
通讯作者：
Gabor, F
中科院分区：
文献类型：
--
作者：
Lochner, N;Lobmaier, C;Gabor, F
银纳米颗粒增强荧光被引入作为表面等离子体共振技术的替代方法，用于实时监测生物识别相互作用或免疫分析。这种方法依赖于在银纳米颗粒表面照射时产生电磁近场的现象。这个场与附近的荧光团的相互作用导致了荧光增强。因此，可以区分主体溶液中的荧光团和表面结合的荧光团。将抗胰岛素抗体按如下顺序固定在银胶表面：用氨基硅烷、银纳米粒子、Fc识别F(Ab)(2)片段和抗胰岛素抗体层层包覆，制成即用微孔板。在平衡条件下，只有在胶体存在的情况下才能检测到荧光素标记的胰岛素；检测下限为250 nM，实时监测时荧光增加了四倍。标记和未标记胰岛素的竞争测定显示，血清中胰岛素的工作范围为10-200 nM。快速单步免疫分析即使在微孔板形式下也很容易进行，其灵敏度与ELISA技术相当，并为实时监测分子识别过程提供了广泛的应用。(C)2003爱思唯尔B.V.保留所有权利。
Silver nanoparticle enhanced fluorescence is introduced as an alternative method to surface plasmon resonance techniques for real time monitoring of biorecognitive interactions or immunoassays. This method relies on the phenomenon that an electromagnetic near field is generated upon illumination on the surface of silver nanoparticles. The interaction of this field with nearby fluorophores results in fluorescence enhancement. Thus, fluorophores in the bulk solution can be discriminated from surface bound fluorophores. Anti-insulin-antibodies were immobilized on the surface of silver colloids in the following order: A ready to use microplate was prepared by bottom up coating with layers of aminosilane, silver nanoparticles, Fc-recognizing F(ab)(2)-fragments and anti-insulin-antibodies. At equilibrium conditions fluorescein-labeled insulin could only be detected in the presence of the colloid; the detection limit was 250 nM, and a fourfold increase in fluorescence was observed upon real time monitoring. The competitive assay of labeled and unlabeled insulin revealed a working range of 10-200 nM insulin in serum. The rapid single step immunoassay is easy to perform even in microplate format, its sensitivity is comparable to ELISA techniques, and offers broad application for real time monitoring of molecular recognitive processes. (C) 2003 Elsevier B.V. All rights reserved.