Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, PR China.
Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, PR China.
Biosens Bioelectron. 2014 Aug 15;58:258-65. doi: 10.1016/j.bios.2014.02.067. Epub 2014 Mar 6.
In this article, plasmon-mediated fluorescence biosensing is reported to be distance independent through a full-coupling strategy that effectively activates the entire plasmon coupling region. This concept is demonstrated through collecting the directional surface plasmon-coupled emission (SPCE) signal from fluorescent silica nanoparticles with a size that matches the entire coupling region. Based on this design, the spatial distribution of the fluorophores is confined by the dimension of the nanoparticle. Therefore, these encapsulated fluorophores occupy the maximum coupling dominant region and optimally utilize the coupling effect. Being different from the conventional plasmon-mediated fluorescence, the enhanced fluorescence response becomes nearly independent of distance changes on a wide dynamic range from 0nm to 30nm between the fluorescent nanoparticles and metal structure. Full-coupling SPCE appropriately enlarges the distribution of fluorophores, ensuring that the coupling dominant region is filled with enough fluorophores at varying distances to create a stable and detectable signal. This scale of distances is well suited for many biorecognition events. Full-coupling SPCE solves signal deviation challenges originating from the susceptible and unpredictable orientation and conformation of biomolecules on the nanoscale. Immunoassays and DNA detection are shown with high and reliable signals, demonstrating the advantages of distance-independent full coupling. Without the need of a complicated and rigorous architecture for precise distance control, full-coupling SPCE offers great promise for a general platform of chip-based biosensing and bioanalysis.
本文报道了一种通过全耦合策略实现的与距离无关的等离子体介导荧光生物传感，该策略有效地激活了整个等离子体耦合区域。通过收集与整个耦合区域相匹配的荧光硅纳米粒子的定向表面等离子体耦合发射（SPCE）信号，证明了这一概念。基于此设计，荧光团的空间分布受到纳米粒子尺寸的限制。因此，这些封装的荧光团占据了最大的耦合主导区域，并优化了耦合效应的利用。与传统的等离子体介导的荧光不同，在荧光纳米粒子和金属结构之间的 0nm 到 30nm 的宽动态范围内，增强的荧光响应几乎与距离变化无关。全耦合 SPCE 适当扩大了荧光团的分布，确保在不同距离下，耦合主导区域内有足够的荧光团填充，以产生稳定可检测的信号。这种距离范围非常适合许多生物识别事件。全耦合 SPCE 解决了由于纳米尺度上生物分子的敏感和不可预测的取向和构象而导致的信号偏差挑战。免疫测定和 DNA 检测显示出高可靠的信号，证明了距离无关的全耦合的优势。全耦合 SPCE 无需复杂和严格的架构来精确控制距离，为基于芯片的生物传感和生物分析提供了一个通用平台。
