Improving the instrumental resolution of sensors based on localized surface plasmon resonance
Improving the instrumental resolution of sensors based on localized surface plasmon resonance
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DOI：
10.1021/ac0601967
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发表时间：
2006-07-01
影响因子：
7.4
通讯作者：
Hook, Fredrik
中科院分区：
文献类型：
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作者：
Dahlin, Andreas B.;Tegenfeldt, Jonas O.;Hook, Fredrik
显示局部表面等离子体共振（LSPR）的纳米级贵金属结构的界面折射率变化引起的比色变化为生物分子识别反应的无标记、基于亲和的检测提供了一种方便的方法。然而，尽管与传统的SPR在性质上相似，但在典型的生物分子识别分析中，LSPR在信噪比（S/N）方面的数据质量明显较低。在这项工作中，提出了通用数据分析算法和一个简单的实验设置，提供了与最先进的SPR系统相当的蛋白质结合的S/N。具体来说，它演示了如何同时记录与共振峰位置成正比的参数的时间变化（速率类似于0.5 Hz），从而产生< 5 x 10(-4) nm的峰位置精度和< 5 x 10（-6）吸光度单位（Abs）的消光噪声水平。反过来，对于典型的蛋白质结合反应，这被证明提供了类似于2000的S/N（相当于< 0.1 ng/cm(2)的检测限）。此外，通过比较不同的LSPR活性贵金属结构对体积和界面折射率变化的不同响应，强调了利用峰值位置和幅度变化的重要性。
The colorimetric variations induced upon changes in interfacial refractive index of nanoscale noble metal structures exhibiting localized surface plasmon resonance (LSPR) provides a convenient means of label-free, affinity-based detection of biomolecular recognition reactions. However, despite being similar in nature to conventional SPR, LSPR has so far suffered from significantly lower data quality in terms of its signal-to-noise ratio (S/N) in typical biomolecular recognition analysis. In this work, generic data analysis algorithms and a simple experimental setup that provide a S/N upon protein binding that is comparable to that of state-of-the art SPR systems are presented. Specifically, it is demonstrated how temporal variations ( rate similar to 0.5 Hz) in parameters proportional to the resonance peak position can be recorded simultaneously, yielding a peak position precision of < 5 x 10(-4) nm and an extinction noise level of < 5 x 10(-6) absorbance units (Abs). This, in turn, is shown to provide a S/N of similar to 2000 ( equivalent to a detection limit of < 0.1 ng/cm(2)) for typical protein binding reactions. Furthermore, the importance of utilizing changes in both peak position and magnitude is highlighted by comparing different LSPR active noble metal architectures that respond differently to bulk and interfacial refractive index changes.