Characterization and application to the detection of single-stranded DNA binding protein of fluorescent DNA-templated copper/silver nanoclusters
Characterization and application to the detection of single-stranded DNA binding protein of fluorescent DNA-templated copper/silver nanoclusters
复制标题
DOI：
10.1039/c1an15258k
复制
发表时间：
2011-01-01
期刊：
影响因子：
4.2
通讯作者：
Chang, Huan-Tsung
中科院分区：
文献类型：
--
作者：
Lan, Guo-Yu;Chen, Wei-Yu;Chang, Huan-Tsung
在具有序列5 '-CCCTTAATCCCC-3'的DNA存在下，通过NaBH_4还原AgNO_3和Cu（NO_3）（2）制备强荧光和稳定的DNA-Cu/Ag纳米粒子的简单策略已被证明。荧光，吸收，X射线光电子能谱（XPS），和电喷雾电离质谱（ESI-MS）测量已被应用到DNA-Cu/Ag纳米粒子的表征。ESI-MS数据显示每个DNA-Cu/Ag NC含有2个Ag和1个Cu原子。低温荧光光谱数据进一步支持了DNA与Ag和Cu原子的相互作用。在Cu ~（2+）存在下，反应时间为1.5 h，比在AgNO_3、NaBH_4和DNA的混合溶液中制备的Ag-DNA纳米粒子的反应时间（120 h）短得多。相对于DNA-Ag NC，DNA-Cu/Ag NC具有更大的荧光（量子产率51.2%对11.5%）。DNA-Cu/Ag NC对单链DNA结合蛋白（SSB）的检测具有高度的灵敏度和选择性，线性范围为1-50 nM，检测限为0.2 nM，信噪比为3。
A simple strategy for the preparation of strongly fluorescent and stable DNA-Cu/Ag NCs from reduction of AgNO3 and Cu(NO3)(2) by NaBH4 in the presence of DNA having a sequence 5'-CCCTTAATCCCC-3' has been demonstrated. Fluorescence, absorption, X-ray photoelectron spectroscopy (XPS), and electrospray ionization-mass spectrometry (ESI-MS) measurements have been applied to the characterization of the DNA-Cu/Ag NCs. The ESI-MS data reveal that each DNA-Cu/Ag NC contained 2 Ag and 1 Cu atoms. The interactions among DNA with the Ag and Cu atoms are further supported by the data of low-temperature fluorescence. In the presence of Cu2+ ions, the reaction time is 1.5 h, which is much shorter than that (120 h) for the preparation of Ag-DNA NCs that are prepared in a mixture of AgNO3, NaBH4 and DNA without containing Cu2+ ions. Relative to the DNA-Ag NCs, the DNA-Cu/Ag NCs have greater fluorescence (quantum yield 51.2% vs. 11.5%). The DNA-Cu/Ag NCs are highly sensitive and selective for the detection of single-stranded DNA binding protein (SSB), with a linear range 1-50 nM and a limit of detection 0.2 nM at a signal-to-ratio of 3.