【摘要】 利用自组装技术将巯基乙醇固定在金电极表面形成巯基乙醇自组装膜修饰金电极,用乙基-（3-二甲基氨丙基）碳二亚胺盐酸盐（EDC）和N-羟基琥珀酰亚胺（NHS）为偶联试剂,分别将鲱鱼精单链DNA（ssDNA）和双链DNA（dsDNA）固定于金电极表面形成ssDNA和dsDNA修饰电极.考察了灿烂甲酚蓝（BCB）在不同DNA修饰电极上的电化学行为,结果表明,BCB在ssDNA和dsDNA修饰电极上的吸附常数分别为1.67×10⁴和3.22×10⁴L·mol^-1,BCB与ssDNA主要以静电作用结合,而与dsDNA作用存在静电和嵌插两种模式.dsDNA对BCB具有更高的亲和力,使BCB可以作为一种有效的电化学杂交指示剂.更多还原

【Abstract】 DNA modified electrode was prepared by covalent immobilization of ssDNA or dsDNA on a mercaptoethanol monolayer self-assembled gold electrode with the help of N-（3-dimethylaminopropyl）-N′-ethylcarbodi- imidehydrochloride （EDC） and N-hydroxysuccinimide （NHS）. The electrochemical behaviors of brilliant cresyl blue （BCB） on ssDNA or dsDNA electrodes were studied. BCB had different binding models with ssDNA or dsDNA and the adsorptive constants were 1.67×10⁴ L·mol^-1 for ssDNA/Au electrode and 3.22×10⁴ L·mol^-1 for dsDNA/Au electrode. BCB bound to ssDNA via electrostatic interaction while bound to dsDNA through both the electrostatic and intercalative models. The results showed that dsDNA had a stronger appetency for BCB, which indicated that BCB was a suitable electroactive indicator.更多还原