Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, Guangdong, 510006, People's Republic of China.
State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin, Guangxi, 541004, People's Republic of China.
J Fluoresc. 2022 Nov;32(6):2189-2198. doi: 10.1007/s10895-022-03012-2. Epub 2022 Aug 28.
The construction of a universal nanoplatform for sensitive detection of multiple targets of interest is of great importance in different research fields. Herein, by ingeniously integrating the target recognition sequences and G-rich sequences into a single-stranded multifunctional DNA probe and adopting TiC nanosheets as an efficient fluorescence quencher, a simple, low-cost and easy operation fluorescence sensing nanoplatform was proposed. Without an analytical target, the hydrogen bond and metal chelate interaction between the target recognition region of the DNA probe and TiC nanosheet induce the selective self-assembly of highly fluorescent thioflavin T (ThT)-intercalated DNA probe onto the surface of TiC nanosheets, resulting in dramatic decrease of fluorescence emitted by ThT-G-quadruplex. In the presence of a target, the target recognition region will selectively bind with the target and the constrained DNA probe is released from the TiC nanosheets surface, leading to enhanced fluorescence recovery of ThT-G-quadruplex. As a proof of concept, the sensitive and selective detection of p53 gene, Hg, and adenosine with the assistance of TiC nanosheets-based fluorescence sensing nanoplatform were successfully realized. Moreover, it is also applicable for the evaluation the level of these analytical targets in real samples. By simply switching the recognition sequences of DNA probe, the universal sensing strategy could also be applied for detecting many other types of targets. The simple and universal sensing nanoplatform is expected to promote wide applications in environment monitoring and bioanalysis.
构建用于敏感检测多个感兴趣目标的通用纳米平台在不同的研究领域都具有重要意义。在此，通过巧妙地将目标识别序列和富含 G 的序列整合到单链多功能 DNA 探针中，并采用 TiC 纳米片作为高效荧光猝灭剂，提出了一种简单、低成本且易于操作的荧光传感纳米平台。在没有分析物的情况下，DNA 探针的目标识别区域与 TiC 纳米片之间的氢键和金属螯合相互作用诱导高度荧光噻嗪 T（ThT）-嵌入 DNA 探针选择性地自组装到 TiC 纳米片表面上，导致 ThT-G-四链体发射的荧光急剧下降。存在目标时，目标识别区域将选择性地与目标结合，约束的 DNA 探针从 TiC 纳米片表面释放，导致 ThT-G-四链体的荧光恢复增强。作为概念验证，成功地利用基于 TiC 纳米片的荧光传感纳米平台实现了对 p53 基因、Hg 和腺苷的灵敏和选择性检测。此外，它还可用于评估实际样品中这些分析物目标的水平。通过简单地切换 DNA 探针的识别序列，通用传感策略也可用于检测许多其他类型的目标。这种简单而通用的传感纳米平台有望在环境监测和生物分析中得到广泛应用。
