功能化核酸适体检测氯霉素可行性研究

Feasibility study of functional aptamer for chloramphenicol detection

目的探讨荧光适体探针用于氯霉素快速检测的可行性。方法设计了一种荧光适体探针,主要包括一段与氯霉素特异性识别的DNA序列,其3’端标记FAM荧光,且有一小段核酸随机结构。当适体探针单独存在时,被氧化石墨烯(graphene oxide,Go)吸附到表面,由于能量共振转移作用使得FAM荧光淬灭;当加入靶标时,由于靶标与适配体探针具有高亲和力,配对形成双链复合物,从Go表面脱离,使FAM的荧光信号得到恢复。结果当25 nmol/L荧光标记适配体探针与1.2μL浓度为1 mg·mL-1 Go溶液共同孵育后,超过95%的荧光信号被Go淬灭。当再加入氯霉素溶液经孵育后,荧光信号得到显著恢复。结论该荧光适体探针能被用于氯霉素样品的快速检测,且对其他小分子检测也具有很大的应用潜力。

Objective To explore the feasibility of rapid detection of chloramphenicol with fluorescent aptamer probe.Methods A fluorescent aptamer probe was designed,consisting of a DNA sequence specifically identified with chloramphenicol,with 3’-end fam-labeled fluorescence,and a small random nucleic acid structure.When the aptamer probe exists alone,it is adsorbed to the surface by graphene oxide(Go),while FAM fluorescence quenched by fluorescence resonance energy transfer.When the target was added,as the target had a high affinity with the aptamer probe,the target was paired to form a double-stranded complex,which was separated from the Go surface and the fluorescence signal of FAM was recovered.Results When the 25 nmol/L fluorescent labeled aptamer probe was incubated with 1.2μL of 1 mg/mL Go solution,more than 95%of the fluorescence signal was quenched by Go.After chloramphenicol solution was added and incubated,the fluorescence signal was obviously recovered.Conclusion The fluorescence aptamer probe can be used for rapid detection of chloramphenicol samples and has great potential for other small molecule detection.