摘要
制备了基于氧化锆（ZrO2）/聚中性红（PNR）修饰电极的电化学DNA传感器。探针DNA通过磷酸基和ZrO2的相互作用组装到电极表面。原子力显微镜（AFM）和电化学方法用于电极的表征。PNR在DNA杂交前后峰电流的变化作为杂交信号,用示差脉冲伏安法对转基因植物CaMV35S启动子基因片段进行测定。结果表明：探针DNA和完全互补的DNA片段杂交后,杂交信号明显变小,峰电流的变化值与其浓度的对数在1.0×10^-11～1.0×10^-8mol/L范围内呈良好的线性关系,检出限为3.46×10^-12mol/L（S/N=3）。此外,传感器能区分互补、单碱基错配、完全错配的DNA序列,已用于样品的测定。
In this paper,a electrochemical DNA sensor based on the ZrO2/poly（neutral red）（PNR） modified electrodes was fabricated.Probe oligonucledotides were immobilized on the ZrO2thin films via the strong affinity between ZrO2and phosphate groups.Electrochemical method and atomic force microscopy were used to characterize the modified electrode.Differential pulse voltammetry was used to detect the CaMV35S transgene gene sequence and the change of peak current of PNR was used as the signal.Results indicated that the peak current of PNR obviously decreased after the probe DNA hybridizing with complementary target ssDNA.The decrease of peak current of PNR was linear with the logarithm of the concentration of the complementary target ssDNA from 1.0 × 10^-11to 1.0 × 10^-8mol/L with a detection limit of 3.46 × 10^-12.mol/L（S/N = 3）.And the DNA sensor can distinguish one-mismatched CaMV35S transgene gene sequence,exhibiting excellent sensitivity,stability and reproducibility.The DNA sensor was applied to the determination of CaMV35S transgene gene sequence in samples with satisfactory results.
出处
《分析试验室》
CAS
CSCD
北大核心
2014年第7期808-811,共4页
Chinese Journal of Analysis Laboratory
基金
安徽省教育厅自然科学基金(KJ2012Z399
KJ2013A247)
安徽省自然科学基金青年基金(1208085QB33
1408085QB41)
宿州学院科研平台开放课题(2012YKF04,2012YKF05)
宿州学院大学生科研立项(KYLXLKYB13-10)资助
关键词
聚中性红
氧化锆
DNA杂交
修饰电极
Poly（neutral red）
ZrO2
DNA hybridization
Modified electrodes
