【作者】 谢琴； 谭誉宇； 郭秋平； 王柯敏； 何春梅； 袁宝银； 万俊； 赵下雨；

【Author】 Qin Xie;Yuyu Tan;Qiuping Guo;Kemin Wang;Chunmei He;Baoyin Yuan;Jun Wan;Xiayu Zhao;State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University,Key Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan Province;

【机构】 化学生物传感与计量学国家重点实验室,湖南大学生物学院； 湖南大学化学化工学院,生物纳米与分子工程湖南省重点实验室；

【摘要】 本文选用本实验室基于细胞筛选技术筛选出来核酸适配体zy1为模式,巧妙地利用了氧化石墨烯可以吸附ssDNA的特性及其对荧光染料的超淬灭能力,成功地构建了一种基于氧化石墨烯的简单快速灵敏的核酸适配体荧光传感器用于人源肝癌细胞株SMMC-7721肿瘤细胞的检测。当样品中存在靶细胞时,荧光基团标记的核酸适配体与细胞结合,导致可检测到较强的荧光强度;当无靶细胞存在时,荧光基团标记的核酸适配体缠绕在氧化石墨烯表面,使得荧光强度大大地降低。最后,在200μL检测体系中,特异地有效地直接检测低至200个SMMC-7721细胞数的样品,此过程无需洗涤和分离。更重要的是,只需更换其他肿瘤细胞的相应的核酸适配体作为识别元件,就可以实现其他肿瘤细胞的检测。更让人兴奋的是,流式细胞术结果表明此方法还可以实现复杂体系的混合细胞检测,不仅进一步说明该方法具有良好的选择性,而且表明了此核酸适配体荧光传感器在生物分析和医疗诊断中的潜在应用。更多还原

【Abstract】 Here, we reported a simple, rapid and sensitive fluorescence method for the direct detection of cancer cells using graphene oxide(GO)-based aptasensor. As proof of concept, an aptamer sequence was used, which selected using a cell-based SELEX strategy in our laboratory for human liver cancer cell line SMMC-7721 with high specificity and high affinity. Samples with the target cells present a high fluorescent intensity while nontarget samples still showed low fluorescent intensity. This GO-based aptasensor exhibited high sensitivity and specificity with the detection limits of 200 SMMC-7721 cells in 200 μL binding buffer with no required washing and separation steps. Furthermore, future design of detectors for other cancer cells only requires changing the recognition element for the target cell. More importantly, flow cytometry was used for specific recognition of the target cells from mixture cells in fetal bovine serum to demonstrate the potential application in medical diagnostics.更多还原