基于三螺旋适体探针的双向开关传感同时灵敏测定四环素和氯霉素  

Simultaneous and sensitive determination of tetracycline and chloramphenicol by two-way switch sensing based on triple helix aptamer probe

作　　者：王子棋 高亚芳 谭心韵 李安祺 鲁理平[1] WANG Ziqi;GAO Yafang;TAN Xinyun;LI Anqi;LU Liping(Key Laboratory of Beijing on Regional Air Pollution Control,Faculty of Environment Science,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学环境科学系,区域大气复合污染防治北京市重点实验室,北京100124

出　　处：《分析试验室》2023年第10期1317-1323,共7页Chinese Journal of Analysis Laboratory

基　　金：国家自然科学基金项目(21876005,21936001,21625501);北京市卓越青年科学家计划项目(BJJWZYJH01201910005017)资助。

摘　　要：设计了基于发卡状三螺旋结构的DNA分子开关荧光传感器,利用适配体特异性识别,实现了对2种目标抗生素的同时灵敏测定。其分子开关结构由一个特异性适配体识别序列和一个双标记的信号探针序(STP)列组成发卡状三螺旋结构。识别四环素的STP两端用芘分子修饰,识别氯霉素的信号探针两端分别用硫化镉量子点(CdS QDs)和金纳米粒子(AuNPs)修饰,适配体序列插入环状(Loop)区域形成三链结构。目标抗生素存在时,识别探针与之结合,释放出信号探针,致使两端发光物质靠近,荧光信号发生显著变化。传感器的荧光发光强度与四环素和氯霉素浓度呈良好的线性关系,线性范围为1×10^(-3)~10μmol/L,检出限为0.3 nmol/L。该方法用于测定鸡蛋中的四环素和氯霉素,结果满意。A DNA molecular switch fluorescence sensor based on hairpin triple helix structure was designed to achieve simultaneous sensitive determination of two target antibiotics by aptamer specific recognition.The molecular switching structure consists of a specific aptamer recognition sequence and a double-labeled signal probe sequence.The two ends of the signal probe for tetracycline recognition were modified with pyrene molecules,and the two ends of the signal probe for chloramphenicol recognition were modified with cadmium sulfide quantum dots(CdS QDs) and gold nanoparticles,respectively.The aptamer sequence was inserted into the loop region to form a three-chain structure.When the target antibiotic was present,the recognition probe bound to it and released a signal probe,bringing the luminescent substance at both ends closer together,and the fluorescence signal changed significantly(enhanced or reduced).The fluorescence intensity of the sensor showed a good linear relationship with the concentrations of tetracycline and chloramphenicol,the linear range was 1×10^(-3)-10 μmol/L,and the detection limit was 0.3 nmol/L.The method was used to determine tetracycline and chloramphenicol in eggs with satisfactory results.

关 键 词：四环素 氯霉素 三螺旋DNA 分子开关 荧光传感器 

分 类 号：O657.3[理学—分析化学]