Department of Chemistry, College of Natural Science, Seoul National University, Seoul, 151-747, Korea.
Analyst. 2010 Mar;135(3):603-7. doi: 10.1039/b920998k. Epub 2010 Jan 21.
This study describes the development and characterization of a novel dendritic signal amplification strategy. It relies on the use of two different Ru(bpy)(3)(2+)-doped silica nanoparticles (Probe(1,2)RSNP and Probe(2c)RSNP) coated with complementary DNAs, which can be simply and conveniently self-assembled to build sandwich-type dendritic architectures on a gold grid. The performance of this dendritic amplification route was demonstrated in conjunction with the electrogenerated chemiluminescent (ECL) detection of the target DNA. Compared to normal amplification, dendritic amplification allowed a 5-fold enhancement of the ECL signals. The higher sensitivity allowed by the dendritic amplification route was attributed to the hybridization between the DNA (Probe(2)DNA) on Probe(1,2)RSNP (normal amplification) and the complementary DNA (Probe(2c) DNA) on the additional Probe(2c)RSNP. As low as 1 fM of 22-bp-long target DNA was clearly detected. The experimental results demonstrated that the ECL intensity achieved through dendritic amplification showed a good linear relationship with the concentration of the target DNA over a wide linear range (10 fM-10 pM).
本研究描述了一种新型的树枝状信号放大策略的开发和特性。它依赖于使用两种不同的 Ru(bpy)(3)(2+)-掺杂二氧化硅纳米粒子（探针 1,2RSNP 和探针 2cRSNP），这些纳米粒子表面涂有互补 DNA，可以简单方便地自组装在金网格上构建三明治型树枝状结构。这种树枝状放大途径的性能与目标 DNA 的电致化学发光（ECL）检测相结合进行了证明。与常规放大相比，树枝状放大使 ECL 信号增强了 5 倍。树枝状放大途径的更高灵敏度归因于探针 1,2RSNP 上的 DNA（探针 2DNA）与额外的探针 2cRSNP 上的互补 DNA（探针 2cDNA）之间的杂交。可以清楚地检测到低至 1 fM 的 22 个碱基对长的目标 DNA。实验结果表明，通过树枝状放大获得的 ECL 强度与目标 DNA 的浓度在很宽的线性范围内（10 fM-10 pM）呈现出良好的线性关系。
