Tuning properties of silver nanoclusters with RNA nanoring assemblies.
Tuning properties of silver nanoclusters with RNA nanoring assemblies.
复制标题
用 RNA 纳米环组件调节银纳米团簇的特性。
作者：
Chelsea E. Flood;M. Wong
将原子解析的 DNA 模板银纳米团簇 (AgNC) 与核酸纳米技术相结合，为工程设计具有独特可调特性的生物无机纳米材料开辟了令人兴奋的新可能性。在这种不可预见的合作中，核酸不仅驱动 AgNC 的形成，而且还促进它们在超组装中的空间组织。在这项工作中，我们确认了这种使用可编程 RNA 环来控制六个单独 AgNC 的形成和光学特性的方法的可行性。发射“红色”（λEXC/λEM = 565/623 nm）和“绿色”（λEXC/λEM = 440/523 nm）的 AgNC 以嵌入 RNA 环的富含胞嘧啶的 DNA 片段为模板。对 RNA 环上形成的 AgNC 的光学特性进行了详细表征。虽然所有“红色”物种随着时间的推移被动转变为“绿色”发射器，但“红色”AgNC 的初始荧光特性和相对稳定性可以通过改变 RNA 环内 AgNC 的相对方向来调节。因此，AgNC 位于 RNA 环中心而不是朝外时，氧化稳定性显着增加。总的来说，我们的研究结果扩展了现有的 AgNC 荧光工具包，同时揭示了 AgNC 电子结构的复杂性以及控制去激发过程的丰富可能性。
Combining atomically resolved DNA-templated silver nanoclusters (AgNCs) with nucleic acid nanotechnology opens new exciting possibilities for engineering bioinorganic nanomaterials with uniquely tunable properties. In this unforeseen cooperation, nucleic acids not only drive the formation of AgNCs but also promote their spatial organization in supra-assemblies. In this work, we confirm the feasibility of this approach using programmable RNA rings to control formation and optical properteis of six individual AgNCs. "Red" (λEXC/λEM = 565/623 nm) and "green" (λEXC/λEM = 440/523 nm) emitting AgNCs are templated on cytosine-rich DNA fragments embedded into the RNA rings. Optical properties of the AgNCs formed on the RNA rings are characterized in detail. While all "red" species passively transition to "green" emitters with time, the initial fluorescent properties and relative stabilities of "red" AgNCs can be regulated by altering the relative orientation of AgNCs within the RNA rings. As such, the oxidative stability increases dramatically for AgNC positioned towards the center of the RNA rings rather than facing outward. Overall, our findings expand the existing AgNC fluorescent toolkit while uncovering the complexity of the AgNC electronic structures with the abundance of possibilities for controlling de-excitation processes.