College of Food Science and Engineering , Ocean University of China , 5 Yushan Road , Qingdao 266003 , China.
Bioengineering Laboratory , RIKEN Cluster for Pioneering Research , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan.
Langmuir. 2019 Sep 10;35(36):11710-11716. doi: 10.1021/acs.langmuir.9b01537. Epub 2019 Aug 27.
The interactions between metal ions and biomolecules are crucial to various bioprocesses. Development of plasmon switching nanodevices that exploit these molecular interactions is of fundamental and technological interest. Here, we show plasmon switching based on rapid aggregation/dispersion of double-stranded DNA-modified gold nanorods (dsDNA-AuNRs) that exhibit colloidal behaviors depending on pairing/unpairing of the terminal bases. The dsDNA-AuNRs bearing a thymine-thymine (T-T) mismatch at the penultimate position undergo spontaneous non-cross-linking aggregation in the presence of Hg due to T-Hg-T base pairing. Inversely, the subsequent addition of cysteine (Cys) gives rise to the removal of Hg from the T-Hg-T base pair to reproduce the T-T mismatch, resulting in stable dispersion of the dsDNA-AuNRs. The chemical-responsive plasmon switch allows for the rapid and repeatable cycles at room temperature. The validity of the present method is further exemplified by developing another plasmon switch fueled by Ag and Cys by installing the Ag-binding DNA sequence in the dsDNA-AuNR.
金属离子与生物分子之间的相互作用对各种生物过程至关重要。开发利用这些分子相互作用的等离子体开关纳米器件具有基础和技术上的重要意义。在这里，我们展示了基于双链 DNA 修饰的金纳米棒（dsDNA-AuNR）的快速聚集/分散的等离子体开关，这些 dsDNA-AuNR 的胶体行为取决于末端碱基的配对/非配对。在汞存在下，位于倒数第二位的胸腺嘧啶-胸腺嘧啶（T-T）错配的 dsDNA-AuNR 会由于 T-Hg-T 碱基配对而自发地进行非交联聚集。相反，随后添加半胱氨酸（Cys）会导致 Hg 从 T-Hg-T 碱基对中去除，从而重新生成 T-T 错配，导致 dsDNA-AuNR 的稳定分散。化学响应等离子体开关允许在室温下快速且可重复的循环。通过在 dsDNA-AuNR 中安装与 Ag 结合的 DNA 序列，利用 Ag 和 Cys 开发另一种等离子体开关，进一步证明了本方法的有效性。
