Enhancing the stability of single-stranded DNA on gold nanoparticles as molecular machines through salt and acid regulation
Enhancing the stability of single-stranded DNA on gold nanoparticles as molecular machines through salt and acid regulation
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通过盐和酸调节增强金纳米颗粒上单链 DNA 作为分子机器的稳定性
DOI：
10.1039/c9tb01238a
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发表时间：
2019
影响因子：
7
通讯作者：
Wei Jiang
中科院分区：
文献类型：
--
作者：
Jiangning Zhang;Jing Jin;Yanqiu Du;Xiang Zhou;Haojun Liang;Wei Jiang
dna功能化金纳米粒子（DNA-AuNPs）在构建类机器纳米器件方面显示出巨大的潜力和令人兴奋的机会。非硫代化的DNA可以通过DNA碱基，如聚腺嘌呤(polyA) -DNA，移植到金表面上。聚a - dna - AuNPs的胶体稳定性对盐和pH有显著的依赖性，影响了AuNPs的组装及其在聚a - dna分子机器中的应用。高盐和低pH有助于polyA-DNA-AuNPs的稳定。在酸性条件下，腺嘌呤可以被质子化并带正电，从而通过静电相互作用增强了poly - dna在金表面的吸附；多种相互作用的协调实现了高DNA接枝密度和胶体稳定性。此外，腺嘌呤的长度对DNA机器的效率有重要影响，而胸腺嘧啶的长度在胸腺嘧啶长度小于等于7时影响不大。在动态多聚a - dna分子机器驱动下，A5-DNA和A9-DNA成功组装了AuNPs。中等浓度的低聚物（50 nM）可以提高DNA杂交效率。基于A9-DNA的分子机器比基于A5-DNA的分子机器效率更高，因为A9-DNA在aunp上的数量更多，这增加了互补DNA链之间碰撞的可能性。因此，聚a - dna功能化纳米颗粒可以作为构建装配有序结构的基本单元，实现动态分子机器，应用于分子诊断领域。
DNA-functionalized gold nanoparticles (DNA–AuNPs) have shown great potential and exciting opportunities for constructing machine-like nanodevices. Nonthiolated DNA can be grafted onto gold surfaces via DNA bases, such as polyadenine (polyA)–DNA. The colloidal stability of polyA–DNA–AuNPs has a significant dependency on salt and pH that affects the assembly of AuNPs and their application in polyA–DNA molecular machines. High salt and low pH value contribute to the stabilization of polyA–DNA–AuNPs. In acid conditions, adenine can be protonated and becomes positively-charged, thus enhancing the adsorption of polyA–DNA onto the gold surface by electrostatic interactions; coordination of multiple interactions achieves a high DNA grafting density and colloidal stability. In addition, the length of adenine has an important effect on the efficiency of the DNA machine, while the length of thymine has little effect when the thymine length is less than or equal to seven. The assembly of AuNPs driven by dynamic polyA–DNA molecular machines was successfully accomplished with A5-DNA and A9-DNA. A moderate concentration of catalyst oligomer (50 nM) could improve the DNA hybridization efficiency. The A9-DNA based molecular machine is more efficient than the A5-DNA based one because of the larger amount of A9-DNA on the AuNPs, which increases the probability of collisions between complementary DNA strands. Therefore, polyA–DNA functionalized nanoparticles can be used as a basic unit to construct assembly-ordering structures and achieve dynamic molecular machines to be applied in the molecular diagnostics field.