†State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Collaborative Innovation Center of Chemistry for Life Sciences, Nanjing, Jiangsu 210093, China.
∥Food and Bioengineering College, Henan University of Science and Technology, Luo-yang, Henan 471023, China.
Anal Chem. 2015 Apr 7;87(7):3936-41. doi: 10.1021/ac504830e. Epub 2015 Mar 11.
The sensitive identification of single nucleotide polymorphisms becomes increasingly important for disease diagnosis, prevention, and practical applicability of pharmacogenomics. Herein, we propose a simple, highly selective, label-free single nucleotide polymorphisms (SNPs) sensing device by electrochemically monitoring the diffusion flux of ferricyanide probe across probe DNA/morpholino duplex functionalized nanochannels of porous anodic alumina. When perfectly matched or mismatched target DNA flows through the nanochannels modified with probe DNA/morpholino duplex, it competes for the probe DNA from morpholino, resulting in a change of the surface charges. Thus, the diffusion flux of negatively charged electroactive probe ferricyanide is modulated since it is sensitive to the surface charge due to the electrostatic interactions in electric double layer-merged nanochannels. Monitoring of the change in diffusion flux of probe enables us to detect not only a single base or two base mismatched sequence but also the specific location of the mismatched base. As is demonstrated, SNPs in the PML/RARα fusion gene, known as a biomarker of acute promyelocytic leukemia (APL), have been successfully detected.
单核苷酸多态性的灵敏识别对于疾病诊断、预防和药物基因组学的实际应用变得越来越重要。在此，我们提出了一种简单、高选择性、无标记的单核苷酸多态性（SNP）传感装置，通过电化学监测铁氰化物探针在多孔阳极氧化铝纳米通道中探针 DNA/吗啉代寡核苷酸双链功能化的纳米通道中的扩散通量。当完全匹配或不匹配的靶 DNA 流过探针 DNA/吗啉代寡核苷酸双链修饰的纳米通道时，它会与探针 DNA 竞争，导致表面电荷发生变化。因此，由于静电相互作用在双电层合并的纳米通道中，带负电荷的电化学活性探针铁氰化物的扩散通量会发生变化。监测探针扩散通量的变化可以使我们不仅能够检测到单个碱基或两个碱基错配序列，还能够检测到错配碱基的特定位置。如所证明的，已成功检测到急性早幼粒细胞白血病（APL）的生物标志物 PML/RARα 融合基因中的 SNP。
