We herein developed a simple and ultrafast electrochemical DNA detection method by utilizing the oxidase-mimicking activity of cerium oxide nanoparticles (CeO₂). In the sensor, the presence of DNA, which electrostatically interacts with CeO₂ and 3,3′,5,5′-tetramethylbenzidine (TMB) substrate, limits the formation of CeO₂-TMB complex that is required for the oxidase-like reaction. As a result, the oxidase-mimicking activity of CeO₂ is not effectively exerted, leading to the significantly diminished electrochemical current signal. With this novel strategy, we successfully determined DNA amplicon derived from Escherichia coli (E. coli) with the total assay time less than 6 min even without the post-purification of DNA amplicon.

我们在这里通过利用氧化铈纳米颗粒（CeO ₂）的氧化酶模拟活性，开发了一种简单且超快速的电化学DNA检测方法。在传感器中，与CeO ₂和3,3'，5,5'-四甲基联苯胺（TMB）底物发生静电相互作用的DNA的存在限制了氧化酶样反应所需的CeO ₂ -TMB复合物的形成。。结果，不能有效地发挥CeO ₂的氧化酶模拟活性，导致电化学电流信号显着降低。有了这个新型的策略，我们成功地确定的DNA扩增子衍生自大肠杆菌（É。大肠杆菌），即使不进行DNA扩增子的后纯化，总检测时间也少于6分钟。