CK-19基因的电化学检测

发布时间：2018-05-06 06:25

  本文选题：CK-19 + Hoechst　； 参考：《福建医科大学》2010年硕士论文

【摘要】： DNA电化学生物传感器是近几年国际热点研究的一类新型生物传感器,它具有仪器简单、分析速度快、灵敏度高等优点而被认为是目前人们寄于最大期望的一类DNA分析方法。 CK-19是一种低分子量的角蛋白,是上皮细胞骨架的一部分。CK-19作为上皮组织的特异性标记物,主要在上皮组织及上皮来源的肿瘤中表达,并在乳腺癌中有较高表达,而在正常外周血、骨髓组织、淋巴结中则不表达,因此可以作为乳腺癌的标志物进行乳腺癌的早期检测。 本文利用自组装的方法,首次将CK-19基因片段作为特异性探针固定在金电极表面,采用交流阻抗法并结合电化学活性指示剂MB对探针固定的条件进行摸索。实验结果表明,该基因片段在电极表面的最大固载量为3.0 umol/L,最佳固定温度、固定时间分别为4℃及20h。 此外,本文还构建了以Hoechst 33258作为杂交指示剂的DNA电化学生物传感器。实验结果表明,Hoechst 33258是一种特异性较强的指示剂,能够有效地区分CK-19基因的互补与非互补序列。CK-19探针电极在pH 7.0的磷酸盐缓冲液(PBS)中,55℃杂交30min,检测效果良好。互补DNA在5.0×10-7~ 5.0×10-6 M浓度范围内,与检测信号成线性关系,检测限达到0.018M,为实际样品的检测研究提供了良好的基础。
[Abstract]:DNA electrochemical biosensor is a new type of biosensor which has been studied in recent years. It has the advantages of simple instrument, fast analysis speed and high sensitivity, so it is considered to be the most expected type of DNA analysis method. CK-19 is a low molecular weight keratin, which is a part of epithelial cytoskeleton. CK-19 is a specific marker of epithelial tissue. But it is not expressed in normal peripheral blood, bone marrow and lymph nodes, so it can be used as a marker for early detection of breast cancer. In this paper, the CK-19 gene fragment was first immobilized on the surface of the gold electrode by self-assembly method. The condition of the probe fixation was explored by using AC impedance method and the electrochemical activity indicator MB. The results showed that the maximum immobilization of the fragment on the electrode surface was 3.0 umoll / L, and the optimal fixation temperature and time were 4 鈩，

本文编号：1851177