化学学报 ›› 2019, Vol. 77 ›› Issue (3): 253-256.DOI: 10.6023/A18100433 上一篇    下一篇

研究通讯

荧光核酸适配体功能化氧化石墨烯生物传感器用于快速检测氯霉素

卢静荷, 谭淑珍, 朱雨清, 李伟, 陈天啸, 王瑶, 刘陈   

  1. 长沙理工大学 化学与生物工程学院 长沙 410114
  • 投稿日期:2018-10-17 发布日期:2019-01-17
  • 通讯作者: 谭淑珍 E-mail:tsz519@163.com
  • 基金资助:

    项目受湖南省教育厅科研基金(No.17C0033)资助.

Fluorescent Aptamer-functionalized Graphene Oxide Biosensor for Rapid Detection of Chloramphenicol

Lu Jinghe, Tan Shuzhen, Zhu Yuqing, Li Wei, Chen Tianxiao, Wang Yao, Liu Chen   

  1. School of Chemical and Biological Engineering, Changsha University of Science and Technology, Changsha 410114
  • Received:2018-10-17 Published:2019-01-17
  • Supported by:

    Project supported by the Scientific Research Fund of Hunan Provincial Education Department (No. 17C0033).

开发了一种无标记和快速的检测方法基于氧化石墨烯(GO)和荧光功能性G-四聚体探针(FGP),可用于定量检测氯霉素(CAP).FGP由氯霉素核酸适配体和富含G碱基的核酸序列组成.核酸适配体用于结合CAP,并且由富含G碱基的核酸序列在K+,Na+离子的作用下形成的G-四聚体,然后与硫磺素T(ThT)结合后用作信号分子.在没有CAP的情况下,FGP通过π-π堆积相互作用被吸附到GO的表面上,阻碍了G-四聚体的形成导致溶液中的荧光强度低.在加入CAP时,FGP的核酸适配体部分可识别并结合CAP以形成复合物,导致其从GO解吸.因此,游离的富含G的碱基序列可以形成G-四聚体结构并与ThT结合,导致溶液的荧光强度增加.我们观察到荧光强度增加与CAP浓度在2~20 nmol/L范围内呈线性关系,检测限为1.45 nmol/L.此外,该检测系统用于检测加标牛奶中的CAP,回收率在93.2%~103.3%之间.这些结果表明,开发的方法可用于有效检测实际样品中的CAP.

关键词: 核酸适配体, 荧光, 氯霉素, G-四聚体, 氧化石墨烯

A label free and rapid fluorescent method for quantitative detection of chloramphenicol (CAP) based on graphene oxide (GO) fluorescence functional G-quadruplex probe (FGP) was developed. The FGP consisted of a choramphenicol aptamer and a G-rich sequence. The aptamer was used to bind CAP and the G-quadruplex formed by G-rich sequence was employed as a signal reporter after binding to Thioflavin T (ThT). In the absence of CAP, the FGP was absorbed onto the surface of GO through π-π stacking interactions, which restrained the G-rich sequence to form a G-quadruplex structure. Thus, the fluorescent intensity of background was low. In the addition of the CAP, the aptamer part of FGP could recognize and bind CAP to form a target-FGP complex, which led to the desorption of the complex from GO. Therefore, the free G-rich sequence could form G-quadruplex structure and bind to ThT, resulting a increase in the fluorescence intensity of the solution. We observed that the fluorescence increasement of the sensing platform had a linear relationship with the concentrations of CAP in the range of 2~20 nmol/L, and the limit of detection was 1.45 nmol/L. Besides, this detection system was applied for detecting CAP in the spiked milk, the recovery rate was between 93.2%~103.3%. These results indicated that this developed method can be used to efficiently recognize CAP in real samples.

Key words: aptamer, fluorescence, chloramphenicol, G-quadruplex, graphene oxide