Highly sensitive grating coupler-based surface plasmon-coupled emission (SPCE) biosensor for immunoassay
Highly sensitive grating coupler-based surface plasmon-coupled emission (SPCE) biosensor for immunoassay
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DOI：
10.1039/c3an00135k
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发表时间：
2013-01-01
期刊：
影响因子：
4.2
通讯作者：
Lynes, Michael A.
中科院分区：
文献类型：
--
作者：
Yuk, Jong Seol;Guignon, Ernest F.;Lynes, Michael A.
我们评估了一种新型的高含量金光栅耦合器的表面等离子体耦合发射（SPCE）生物传感器系统的性能。该系统生物传感器芯片表面的聚电解质（PEL）层采用逐层沉积（LbL）技术在金表面形成，以从金表面空间分离荧光团，并作为蛋白质固定的连接层。通过表面等离子体共振（SPR）分析和椭偏仪测定了PEL间隔层的特性。在主导淬火范围（10 nm）以上，随着间隔层厚度的增加，SPCE响应减小。两层聚（二烯基二甲基氯化铵）和聚（丙烯酸）的PEL层被发现是一种有效的间隔剂，可以最大限度地减少淬火效应，同时最大化直接和三明治免疫分析格式的SPCE响应。使用该优化间隔层结构的小鼠IgG三明治免疫分析显示出剂量依赖性，根据3 σ规则检测限为1 pg ml（-1）。使用这种方法可以分析未分离的人血清中人IgG浓度的9对数动态范围。这些结果显示了基于光栅耦合器的SPCE生物传感器作为高含量分析的敏感平台的潜力。
We have evaluated the performance of a novel high-content gold grating coupler-based surface plasmon-coupled emission (SPCE) biosensor system. The polyelectrolyte (PEL) layer on the system's biosensor chip surface was formed on the gold surface using a layer-by-layer (LbL) deposition technique to spatially separate fluorophores from the gold surface and as a linker layer for protein immobilization. The characteristics of the PEL spacer layers were determined by surface plasmon resonance (SPR) analysis and by ellipsometry. The SPCE response decreased as the spacer layer thickness increased above a dominant quenching range (10 nm). Two PEL layers of poly(diallyldimethylammonium chloride) and poly(acrylic acid) were found to be an effective spacer that minimized the quenching effect while maximizing SPCE responses for both direct and sandwich immunoassay formats. A mouse IgG sandwich immunoassay using this optimized spacer layer configuration showed a dose-dependent response with a 1 pg ml(-1) limit of detection by the 3 sigma rule. A nine log dynamic range of human IgG concentrations in unfractionated human serum could be analyzed using this approach. These results show the potential of the grating coupler-based SPCE biosensor as a sensitive platform for high-content analysis.