中文摘要：

以DNA为模板,通过一步法合成了一种银铂双金属纳米簇（DNA-Ag/Pt NCs）,其粒径为2-4 nm,并表现出较强的过氧化物模拟酶活性,能催化H2O2氧化TMB使溶液变蓝色。基于此特性,结合Hg^2＋可与胸腺嘧啶碱基形成T-Hg^2＋-T结构,设计研制了一种非标记的电化学传感器,用于Hg^2＋的灵敏特异性检测。实验结果表明,在最佳条件下,该传感器的检测范围为0.65-3.5 nmol/L,检出限达0.17 nmol/L,能较好地识别Hg2＋。该传感器有望用于实际水样中痕量汞的检测。

英文摘要：

In this paper,a facile one-step approach to synthesize DNA-templated Ag / Pt bimetallic nanoclusters was developed.The obtained DNA-templated Ag / Pt bimetallic nanoclusters（DNA-Ag / Pt NCs） with diameters about 2-4 nm display a high efficient peroxidase-like catalytic activity,which can catalyze hydrogen peroxide（H2O2）-mediated oxidation of the substrate,3,3＇,5,5＇-tetramethylbenzidine（TMB）,to produce a blue color reaction.Based on this,the hairpin structure of thymine-Hg^2 ＋-thymine（T-Hg^2 ＋-T） interaction was utilized to design an unlabeled DNA electrochemical sensor for the Hg^2 ＋detection with high sensitivity and selectivity.Under the optimum conditions,the sensor showed a good linear relationship in the range of 0.65-3.5 nmol / L with a detection limit as low as 0.17 nmol / L and also exhibited an ultra high discrimination ability for Hg^2 ＋.All above properties make the sensor a promising candidate for Hg2 ＋trace detection in real water samples.