Ma Jin-Liang, Yin Bin-Cheng, Ye Bang-Ce
Lab of Biosystem and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science & Technology, Shanghai 200237, P. R. China.
Analyst. 2016 Feb 21;141(4):1301-6. doi: 10.1039/c5an02446c.
It is well-known that proximity-dependent probes containing an analyte recognization site and a signal formation domain could be assembled specifically into a sandwich-like structure (probe-analyte-probe) via introducing an analyte. In this work, using the design for zirconium ion (Zr(4+)) detection as the model, we develop a novel and reliable proximity-dependent DNA-scaffolded silver nanocluster (DNA/AgNC) probe for Zr(4+) detection via target-induced emitter proximity. The proposed strategy undergoes the two following processes: target-mediated emitter pair proximity as target recognition implement and the synthesis of DNA/AgNCs with fluorescence as a signal reporter. Upon combination of the rationally designed probe with Zr(4+), the intact templates were obtained according to the -PO3(2-)-Zr(4+)-PO3(2-)- pattern. The resultant structure with an emitter pair serves as a potent template to achieve highly fluorescent DNA/AgNCs. To verify the universality of the proposed proximity-dependent DNA/AgNC probe, we extend the application of the proximity-dependent probe to DNA and adenosine triphosphate (ATP) detection by virtue of a specific DNA complementary sequence and ATP aptamer as a recognition unit, respectively. The produced fluorescence enhancement of the DNA/AgNCs in response to the analyte concentration allows a quantitative evaluation of the target, including Zr(4+), DNA, and ATP with detection limits of ∼3.00 μM, ∼9.83 nM, and ∼0.81 mM, respectively. The proposed probe possesses good performance with simple operation, cost-effectiveness, good selectivity, and without separation procedures.
众所周知，含有分析物识别位点和信号形成域的邻近依赖性探针可以通过引入分析物特异性组装成三明治状结构（探针-分析物-探针）。在这项工作中，以锆离子（Zr(4+)）检测设计为模型，我们开发了一种新型且可靠的邻近依赖性DNA支架银纳米簇（DNA/AgNC）探针，用于通过靶标诱导的发射体邻近实现Zr(4+)检测。所提出的策略经历以下两个过程：靶标介导的发射体对邻近作为靶标识别手段以及以荧光作为信号报告分子合成DNA/AgNCs。将合理设计的探针与Zr(4+)结合后，根据-PO3(2-)-Zr(4+)-PO3(2-)-模式获得完整模板。所得具有发射体对的结构作为有效的模板以实现高荧光的DNA/AgNCs。为了验证所提出的邻近依赖性DNA/AgNC探针的通用性，我们分别借助特异性DNA互补序列和ATP适体作为识别单元，将邻近依赖性探针的应用扩展到DNA和三磷酸腺苷（ATP）检测。DNA/AgNCs响应分析物浓度产生的荧光增强允许对包括Zr(4+)、DNA和ATP在内的靶标进行定量评估，检测限分别约为3.00 μM、约9.83 nM和约0.81 mM。所提出的探针具有操作简单、成本效益高、选择性好且无需分离步骤的良好性能。
