基于DNA步行器的适配体传感器快速检测新冠病毒

DNA walker-based aptasensor for rapid detection of SARS-CoV-2

为开发一种基于DNA步行器的适配体传感器以快速检测新冠病毒RBD。首先制备DNA walker与适配体的复合链,当新冠病毒RBD存在时,竞争性结合适配体,释放DNA walker。通过电还原和共价键和作用制得发夹探针修饰电极,利用DNAzyme驱动的DNA walker在电极表面持续行走,从而不断剪切电极信号探针,增强响应信号,实现新冠病毒蛋白快速检测。检测限(LOD)为3.3 pg/mL(S/N=3),线性范围为0.01~70 ng/mL。该适配体传感器具有优异的稳定性(RSD=4.51%)、重现性(RSD=2.87%)和选择性。在人唾液样本中检测SARS-CoV-2 RBD时回收率为104.51%~107.67%,RSD为4.39%~5.26%。

A DNA walker-based aptasensor was developed for rapid detection of the SARS-CoV-2 RBD.First,a composite chain of DNA walker and aptamer was prepared,which competitively bound to the SARS-CoV-2 RBD and released the DNA walker.A hairpin probe-modified electrode was prepared through electroreduction and covalent bonding,and the DNA walker,driven by DNAzyme,continuously walked on the electrode surface,constantly cleaving the electrode signal probe to enhance the response signal and achieve rapid detection of the SARS-CoV-2 protein.The limit of detection(LOD)was 3.3 pg/mL(S/N=3),and the linear range was 0.01-70 ng/mL.This aptasensor exhibited excellent stability(RSD=4.51%),reproducibility(RSD=2.87%),and selectivity.The recovery rate of detecting SARS-CoV-2 RBD in human saliva samples was 104.51%-107.67%,with an RSD of 4.39%-5.26%.