两种DNA分子同时检测的逻辑门及半加器的构建

本研究利用滴涂法和电沉积法构建了氧化石墨烯/金纳米粒子复合膜修饰电极(GCE/GO/AuNPs),基于目标DNA和探针结合前后探针在电极表面构型的变化导致电化学信号变化,实现对大肠杆菌(E.coli)DNA和沙门氏菌(Sal)DNA的智能识别。以目标物为输入信号,分别以Σ|ΔI|和|ΔIMB/ΔIFc|为输出,构建了"AND"型和"XOR"型DNA分子逻辑门,提出了一种新型的可用于逻辑运算的半加器模型。采用方波伏安法(SWV)检测两种标记探针电流变化值Σ|ΔI|,其与E.coli DNA和Sal DNA浓度的对数值在1.0×10~(-13)~1.0×10~(-8) mol·L~(-1)范围内呈现良好的线性关系,检出限(S/N=3)分别为3.2×10~(-14) mol·L~(-1)和1.7×10~(-14) mol·L~(-1)。

Construction of Logic Gates and Half Adder for Simultaneous Detection of Two DNA Molecules

In this work,the composite film modified glassy carbon electrode(GO/AuNPs/GCE) was prepared by drop coating and electrodeposition method.E.coli DNA and Sal DNA can be detected simultaneously and intelligently due to the current change when target oligonucleotides reacted with probes.The "AND" and "XOR" DNA molecular logic gates were constructed with the target DNAs as the inputs and ∑ ｜△I｜ and ｜ △IMB/△IFc｜ as different outputs.Correspondingly,a new half-adder calculation model for logic operation was proposed.The current sum ∑｜ △I｜ of two probes detected by SWV was linear to the logarithm value of concentraion for E.coli DNA and Sal DNA in the range of 1.0 ×10 13-1.0×10 8 mol· L 1,and the detection limit was 3.2×10-14 mol· L-1 and 1.7×10 14mol· L 1 (S/N =3),respectively.