新型无标记且可重复使用的电化学细胞传感器的研究及其高灵敏检测和特异性收集循环肿瘤细胞

发布时间：2018-06-17 17:27

本文选题：循环肿瘤细胞 + 无标记　；参考：《重庆医科大学》2017年硕士论文

【摘要】：目的癌症是全球死亡率最高的疾病,其引起死亡的主要原因是肿瘤细胞的侵袭及转移,所以对肿瘤转移的早期监测具有重要的临床价值。血液中的循环肿瘤细胞包含大量的肿瘤表型信息,是肿瘤转移的重要标志物。因此,高灵敏的检测与高特异的收集循环肿瘤细胞对癌症转移的早期监测以及分子机制的研究是十分有意义的。方法基于电化学阻抗谱法设计一种新型无标记的电化学细胞传感器用于循环肿瘤细胞的检测。首先,将6-巯基-1-乙醇(MCH)固定在金电极表面,使捕获探针定向插入MCH分子所形成的间隙中,可促进捕获探针站立且更加均匀地分布在电极表面,进而提高细胞传感器的灵敏度与稳定性。利用高亲和力的适体特异地识别肿瘤细胞膜上过表达的上皮细胞粘附分子捕获靶细胞以提高检测特异性。由于细胞具有很强的阻碍电子转移特性,因此我们选择电化学阻抗谱法对其进行检测。检测后,借助脱氧尿嘧啶水解酶水解适体与捕获探针结合部分的脱氧尿苷实现电极的重复利用以及循环肿瘤细胞的收集。结果此传感器具有良好稳定性和可重复性,检测范围可达到30-1×106cells/m L,检测限可低至10cells/m L。并且该细胞传感器凭借上皮细胞黏附分子与相应适体的特异性结合可精准的在实际血液样本中区分出靶细胞。此细胞传感器还可通过脱氧尿嘧啶水解酶特异性切除适体与捕获探针结合部分的脱氧尿苷,成功地实现电极的8次重复利用及循环肿瘤细胞的富集。结论综上所述,我们设计的细胞传感器有很大的潜力可以应用于临床,可望对癌症的转移进行早期监测。
[Abstract]:Objective Cancer is the disease with the highest mortality in the world, and the main cause of death is the invasion and metastasis of tumor cells, so it has important clinical value for early monitoring of tumor metastasis. Circulating tumor cells in blood contain a lot of phenotypic information and are important markers of tumor metastasis. Therefore, high sensitive detection and high specific collection of circulating tumor cells for early detection of cancer metastasis and molecular mechanisms are of great significance. Methods A novel unlabeled electrochemical cell sensor was designed based on electrochemical impedance spectroscopy (EIS) to detect circulating tumor cells. First of all, by immobilization of 6-mercapto-1-ethanolol (MCH) on the surface of the gold electrode, the trapping probe is inserted into the gap formed by the MCH molecule, which can promote the trap probe to stand and distribute more evenly on the electrode surface. Furthermore, the sensitivity and stability of the cell sensor are improved. High affinity aptamers are used to specifically recognize the overexpression of epithelial cell adhesion molecules on tumor cell membranes to capture target cells in order to improve detection specificity. Because of the strong resistance to electron transfer, we choose electrochemical impedance spectroscopy (EIS) to detect the cells. After detection, deoxyuridine was used to reuse the electrode and collect circulating tumor cells by using deoxyuridine hydrolase to hydrolyze aptamer and capture probe part of deoxyuridine. Results the sensor has good stability and repeatability. The detection range can reach 30-1 脳 106cells/m / L, and the detection limit can be as low as 10cells/m L. The cell sensor can accurately distinguish target cells from actual blood samples by the specific binding of epithelial cell adhesion molecules to corresponding aptamers. This cell sensor can also remove deoxyuridine from aptamer and capture probe specifically by deoxyuridine hydrolase, and successfully reuse the electrode for 8 times and enrich tumor cells in circulation. Conclusion in conclusion, the cell sensor designed by us has great potential for clinical application and can be used for early detection of cancer metastasis.
【学位授予单位】：重庆医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R730.43;TP212

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