School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan.
Analyst. 2010 Mar;135(3):595-602. doi: 10.1039/b919969a. Epub 2010 Jan 19.
We present a new type of nanoparticle-based DNA sensor using surface-enhanced Raman scattering (SERS) on gold nanoparticle (Au NP) aggregates formed by DNA photoligation. The DNA sensor exploits the photoligation reaction between oligodeoxynucleotides (ODNs) attached to the surfaces of Au NPs in the presence of target DNA (T-DNA). When hybridization takes place between the ODNs and T-DNA, Au NPs are covalently crosslinked to form aggregates via photoligation. Once the NP aggregates are formed, the interspace between Au NPs in the aggregate act as a stable "hot spot", and a SERS signal from the Raman-active molecules (sodium cacodylate) present in the hot spot is easily and sensitively detected. In contrast, a SERS signal is not detected if the hybridization is unsuccessful, because the stable hot spot does not form. This DNA sensor does not require an enzymatic reaction, fluorescent dye, precise temperature control, or complicated operating procedures.
我们提出了一种新型的基于纳米粒子的 DNA 传感器，该传感器利用金纳米粒子（Au NP）聚集体的表面增强拉曼散射（SERS），这些聚集体是由 DNA 光连接形成的。该 DNA 传感器利用在存在靶 DNA（T-DNA）的情况下，连接到 Au NPs 表面的寡脱氧核苷酸（ODN）之间的光连接反应。当 ODN 与 T-DNA 之间发生杂交时，Au NPs 通过光连接共价交联形成聚集体。一旦形成 NP 聚集体，聚集体中 Au NPs 之间的间隔就充当稳定的“热点”，并且可以容易且灵敏地检测到存在于热点中的拉曼活性分子（正丁基二甲氧基硅烷）的 SERS 信号。相反，如果杂交不成功，则不会检测到 SERS 信号，因为不会形成稳定的热点。该 DNA 传感器不需要酶反应，荧光染料，精确的温度控制或复杂的操作程序。
