Abstract In this study, we reported an electrochemical assay for detecting circulating tumor cells (CTCs) in whole blood. Breast cancer cell MCF-7 was chosen as a model for study. Fe3O4 magnetic nanospheres (MNs) modified with anti-epithelial cell adhesion molecule (EpCAM) antibody were utilized to capture MCF-7 from samples and gold nanoparticles modified LiFePO4 (LiFePO4/Au) particles were chosen as electrochemical label. Aptamer can be linked onto LiFePO4/Au via Au-S bond, and then the LiFePO4/Au-aptamer complex can specifically bind to the MUC1 protein that is over-expressed on the cell surface of MCF-7. Electrochemical signals are generated by the reaction of phosphate in LiFePO4 with molybdate to form redox molybdophosphate. The utilization of LiFePO4 for signal probe may expand the application of LiFePO4 in biosensing fields.

中文翻译：

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基于 LiFePO4 电化学探针检测循环肿瘤细胞的电化学方法

摘要 在本研究中，我们报道了一种用于检测全血中循环肿瘤细胞 (CTC) 的电化学分析方法。选择乳腺癌细胞MCF-7作为研究模型。使用抗上皮细胞粘附分子 (EpCAM) 抗体修饰的 Fe3O4 磁性纳米球 (MNs) 从样品中捕获 MCF-7，并选择金纳米粒子修饰的 LiFePO4 (LiFePO4/Au) 颗粒作为电化学标记。适体可以通过 Au-S 键连接到 LiFePO4/Au 上，然后 LiFePO4/Au-适体复合物可以特异性结合在 MCF-7 细胞表面过表达的 MUC1 蛋白。电化学信号是由 LiFePO4 中的磷酸盐与钼酸盐反应生成氧化还原钼磷酸盐而产生的。LiFePO4作为信号探针的应用可能会扩大LiFePO4在生物传感领域的应用。