Localized surface plasmon resonance (LSPR) study of DNA hybridization at single nanoparticle transducers
Localized surface plasmon resonance (LSPR) study of DNA hybridization at single nanoparticle transducers
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DOI：
10.1007/s11051-013-1531-7
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发表时间：
2013-03
影响因子：
2.5
通讯作者：
T. Schneider;N. Jahr;J. Jatschka;A. Csáki;O. Stranik;W. Fritzsche
中科院分区：
文献类型：
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作者：
T. Schneider;N. Jahr;J. Jatschka;A. Csáki;O. Stranik;W. Fritzsche
研究了DNA-DNA相互作用对单个80 nm金纳米粒子局域表面等离子体共振的影响。因此，捕获DNA链在颗粒表面的附着和分析物DNA与固定的捕获DNA的序列特异性DNA结合（杂交）都是研究的主题。基板连接化学的影响，DNA的包装密度控制的辅助层的小分子，和距离增加的连接器上的LSPR效率的影响进行了研究。所产生的信号变化可能与分析物DNA与固定的捕获DNA的更高杂交效率有关。随后附加的DNA链到该系统的研究，这允许多步检测结合和阐明所产生的共振位移。通过与不同浓度的分析物DNA孵育，确定所用DNA系统的检测限。虽然该方法允许无标记检测，但我们表明，额外的标记物，如20 nm金颗粒标记，可显著增加信号，从而提高灵敏度。对不同DNA长度的共振位移的研究表明，与较长的DNA分子（46个碱基）相比，较短的DNA分子（20个碱基）的每碱基共振位移更强。
The effect of DNA–DNA interaction on the localized surface plasmon resonance of single 80 nm gold nanoparticles is studied. Therefore, both the attachment of the capture DNA strands at the particle surface and the sequence-specific DNA binding (hybridization) of analyte DNA to the immobilized capture DNA is subject of investigations. The influence of substrate attachment chemistry, the packing density of DNA as controlled by an assisting layer of smaller molecules, and the distance as increased by a linker on the LSPR efficiency is investigated. The resulting changes in signal can be related to a higher hybridization efficiency of the analyte DNA to the immobilized capture DNA. The subsequent attachment of additional DNA strands to this system is studied, which allows for a multiple step detection of binding and an elucidation of the resulting resonance shifts. The detection limit was determined for the utilized DNA system by incubation with various concentration of analyte DNA. Although the method allows for a marker-free detection, we show that additional markers such as 20 nm gold particle labels increase the signal and thereby the sensitivity significantly. The study of resonance shift for various DNA lengths revealed that the resonance shift per base is stronger for shorter DNA molecules (20 bases) as compared to longer ones (46 bases).