Department of Chemistry, Beijing Normal University, Beijing, China.
Biosens Bioelectron. 2011 Sep 15;27(1):187-91. doi: 10.1016/j.bios.2011.06.013. Epub 2011 Jun 17.
The presence of Ni(2+) enables us to distinguish the presence of single-nucleotide mismatches in PNA (peptide nucleic acids)-DNA films on gold electrodes by electrochemical impedance spectroscopy (EIS). With the help of a modified Randles' equivalent circuit, differences in the charge transfer resistance (ΔR(CT)) before and after the addition of Ni(2+) are a diagnostic measure for the presence of single-nucleotide mismatch. The approach works under real-life conditions with concentrations of the DNA target strand down to 10 fM, and a PNA capture probe is used to genotype the single-nucleotide mismatch in apoE 4 related to Alzheimer's disease (AD).
镍（Ni(2+)）的存在使我们能够通过电化学阻抗谱（EIS）区分金电极上 PNA（肽核酸）-DNA 膜中存在的单碱基错配。借助改进的 Randles 等效电路，添加 Ni(2+)前后的电荷转移电阻（ΔR(CT)）的差异是单碱基错配存在的诊断指标。该方法在实际条件下可用于浓度低至 10 fM 的 DNA 靶链，并使用 PNA 捕获探针对与阿尔茨海默病（AD）相关的载脂蛋白 E4 中的单碱基错配进行基因分型。
