磁性富集荧光法检测大肠杆菌

发布时间：2018-08-29 12:41

【摘要】：为研究大肠杆菌的高灵敏快速检测方法,建立一种基于萘酰亚胺标记的DNA探针和磁性四氧化三铁氧化石墨烯分离的大肠杆菌O157:H7检测方法。将标记萘酰亚胺的ssDNA(单链DNA)作为捕获探针吸附在磁性氧化石墨烯表面,当目标ssDNA存在时,捕获探针与之部分杂交,利用磁场将目标ssDNA捕获并富集。然后加入释放探针完成杂交,使标记荧光的捕获探针从磁性氧化石墨烯的表面释放出来,通过测定溶液荧光强度可以实现大肠杆菌O157:H7的高灵敏检测。实验结果表明:在一定条件下,O157:H7数量的对数值和荧光强度与空白值荧光强度的比值(F/F_0)呈线性关系,线性范围为150~1.5×10~6个/m L,经过富集后检出限可达100个/m L。该方法灵敏度高,检出限低,耗时较短,操作简单,为致病菌的高灵敏检测提供新思路。
[Abstract]:In order to study the highly sensitive and rapid detection method of Escherichia coli, a DNA probe based on naphthalimide and a O157:H7 method for the separation of magnetic graphene tetroxide were developed. SsDNA (single-stranded DNA) labeled with naphthalene imide was used as a trap probe to adsorb on the surface of magnetic graphene oxide. When the target ssDNA existed, the trap probe was hybridized with part of it, and the target ssDNA was captured and enriched by magnetic field. Then the labeled fluorescence capture probe was released from the surface of the magnetic graphene oxide by adding the release probe to complete the hybridization. The highly sensitive detection of Escherichia coli O157:H7 could be achieved by measuring the fluorescence intensity of the solution. The experimental results show that the logarithmic value of O 157: h 7 and the ratio of fluorescence intensity to blank fluorescence intensity (F/F_0) show a linear relationship under certain conditions. The linear range is 150 ~ 1.5 脳 10 ~ 6 / mL, and the detection limit can reach 100 / mL after enrichment. This method has the advantages of high sensitivity, low detection limit, short time consuming and simple operation, which provides a new method for the sensitive detection of pathogenic bacteria.
【作者单位】：湖南大学环境科学与工程学院环境生物与控制教育部重点实验室;
【基金】：国家自然科学基金资助项目(51541801)~~
【分类号】：O657.3

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