Shen Huawei, Deng Wuquan, He Yirui, Li Xinrun, Song Jinlin, Liu Rui, Liu Hua, Yang Gangyi, Li Ling
Key Laboratory of Medical Diagnostics of Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, 400016, China; Clinical Laboratory Medicine Center, Chongqing Hospital of Traditional Chinese Medicine, Chongqing, 400021, China.
Chongqing Emergency Medical Center, Chongqing, 400014, China.
Biosens Bioelectron. 2020 Nov 15;168:112516. doi: 10.1016/j.bios.2020.112516. Epub 2020 Aug 28.
Herein, based on dual signal amplification by CeO@Ir nanorods (Ce@IrNRs) and enzyme-free DNA walker, a novel electrochemical aptasensor was developed for simultaneous isolation and detection of circulating tumor cells (CTCs). A membrane protein MUC1-targeting aptamer was used to specifically recognize and capture MCF-7 cells. Uracil DNA glycosylase could hydrolyze deoxyuracils of the aptamer to isolate the captured cells. Novel Ce@IrNRs with large surface area and high peroxidase activity were synthesized to amplify the signal, and the enzyme-free DNA walker was applied to release more signal probes combined with Ce@IrNRs. Furthermore, to reduce steric hindrance by cells, the signal probes rather than the target cells, were directly combined with the electrode. The aptasensor could detect CTCs in the range of 2 to 2 × 10 cells mL with a limit of detection 1 cell mL. The developed aptasensor, which can simultaneously isolate and detect CTCs, has great application potential in the early monitoring of tumor metastasis and in individualized treatment.
在此，基于CeO@Ir纳米棒（Ce@IrNRs）和无酶DNA步行器的双信号放大作用，开发了一种新型电化学适体传感器，用于同时分离和检测循环肿瘤细胞（CTC）。一种靶向膜蛋白MUC1的适体用于特异性识别和捕获MCF-7细胞。尿嘧啶DNA糖基化酶可水解适体中的脱氧尿嘧啶以分离捕获的细胞。合成了具有大表面积和高过氧化物酶活性的新型Ce@IrNRs以放大信号，并应用无酶DNA步行器释放更多与Ce@IrNRs结合的信号探针。此外，为了减少细胞的空间位阻，将信号探针而非靶细胞直接与电极结合。该适体传感器能够在2至2×10个细胞/毫升的范围内检测CTC，检测限为1个细胞/毫升。所开发的能够同时分离和检测CTC的适体传感器在肿瘤转移的早期监测和个体化治疗中具有巨大的应用潜力。
