基于硫化镉纳米团簇标记DNA电化学传感的研究

合成了表面具有自由羧基的硫化镉纳米团簇，以乙基-（3-二甲基丙基）碳二 亚胺盐酸盐为偶联活化剂，将其标记于人工合成的5'端氨基修饰的寡聚核苷酸片段 上，制备成CdS纳米团簇标记DNA探针，该寡聚核苷酸片段与大肠杆菌肠毒素基因相 关。在一定的条件下，使基与固定晨玻碳电极表面的待测DNA序列进行杂交反应， 利用阳极溶出示差脉冲伏安法（ASDPV）间接测定Cd的量，实现对互补、非互补 DNA片段的识别和电化学检测，从而对大肠杆菌肠毒素基因片段识别和检测。

Cadmium Sulfide Nanocluster-based Electrochemical Sensing ofDNA Hybridization

Synthesis of cadmium sulfide ( CdS) nanoclusters and its application in an electrochemical DNA hybridization detection were described. The nanoclusters were successfully labeled to a 5'-amino group capped oligonucleotides probe that is related to the colitoxin gene. The DNA genetic sensing assay relies on the target oligonucleotides on the glassy carbon electrode (GCE) hybridized with the CdS nanocluster-oligonucleotides DNA probe. Hybridization events between the probe aid target were monitored by the release of the CdS anchored on the hybrids by oxidative dissolution and the indirect determination of the solubilized Cd~(2+) ions by sensitive anodic stripping voltammetry (ASV) . The detection limit is 10 pmol/L of the complementary target oligonucleotides.