G-rich oligonucleotide-functionalized gold nanoparticle aggregation
G-rich oligonucleotide-functionalized gold nanoparticle aggregation
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DOI：
10.1007/s00216-007-1126-1
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发表时间：
2007-04-01
影响因子：
4.3
通讯作者：
Yu, Ru-Qin
中科院分区：
文献类型：
--
作者：
Wu, Zai-Sheng;Guo, Meng-Meng;Yu, Ru-Qin
富含鸟嘌呤的DNA序列通常通过Hoogsteen氢键形成螺旋四重结构。研究了纳米颗粒的聚集行为，纳米颗粒与dna的比例为1:60，具有末端为4鸟嘌呤的27碱基序列。在一定程度上，金纳米粒子之间的鸟嘌呤四重结构促进了纳米粒子的聚集。然而，金属离子在纳米颗粒表面的配位位点被部分钝化：富鸟嘌呤DNA-GNPs的稳定性略低于普通DNA-GNPs，纳米颗粒组装的金属离子特异性大幅降低。因此，提出了一种富鸟嘌呤序列修饰GNPs聚集的机制。通过调节富含鸟嘌呤的DNA序列，可以在高离子强度下获得稳定的富鸟嘌呤序列功能化纳米颗粒溶液。富含鸟嘌呤序列修饰纳米颗粒的可控制性使DNA二级结构成为DNA分析和疾病诊断的潜在有用候选物。
Guanine-rich DNA sequences commonly form helical quadruplex structures via Hoogsteen hydrogen bonds. The aggregation behavior of the nanoparticles, which are functionalized with four-guanine-terminated 27-base sequences at a nanoparticle-to-DNA ratio of 1:60, is investigated. To some extent, the guanine-quadruplex structures between the gold nanoparticles (GNPs) promote nanoparticle aggregation. However, the coordination site of the metal ion on the nanoparticle surface is partially passivated: the stability of guanine-rich DNA-GNPs is slightly lower than that of the usual DNA-GNPs, and the metal-ion specificity of nanoparticle assembly is substantially decreased. Thus, a mechanism for the aggregation of guanine-rich sequence-modified GNPs is proposed. It is possible to obtain a stable guanine-rich sequence-functionalized nanoparticle solution at high ionic strength by regulating guanine-rich DNA sequences. The controllability of guanine-rich sequence-modified nanoparticles makes the secondary structure of DNA a potentially useful candidate for DNA analysis and disease diagnostics.