基于荧光共轭聚合物和氧化石墨烯的核酸外切酶I检测  

Detecting exonuclease I based on fluorescent conjugated polymers and graphene oxide

作　　者：程昆淇 高梦莹 邢佳贝 赵一帆 卢宏飞 刘学国[2] 邢小静 CHENG Kunqi;GAO Mengying;XING Jiabei;ZHAO Yifan;LU Hongfei;LIU Xueguo;XING Xiaojing(College of Chemistry and Pharmaceutical Engineering,Nanyang Normal University,Nanyang 473061,China;Department of Biology and Chemical Engineering,Nanyang Institute of Technology,Nanyang 473004,China)

机构地区：[1]南阳师范学院化学与制药工程学院,南阳473061 [2]南阳理工学院生物与化学工程学院,南阳473004

出　　处：《分析试验室》2024年第4期541-546,共6页Chinese Journal of Analysis Laboratory

基　　金：河南省科技攻关项目(202102110111,222102110335);河南省青年骨干教师培育基金(2021GGJS123);南阳师范学院国家自然科学基金培育基金(2022PY007)资助。

摘　　要：核酸外切酶I(Exo I)作为一种重要的核酶参与了许多生物学过程,具有维持遗传信息稳定性的功能,因此建立有效检测Exo I活性的方法具有重要的研究价值。基于聚芴类荧光共轭聚合物-poly[(9,9-bis(6′-N,N,N-trimethyl-ammonium)hexyl)-fluorenylene phenylene dibromide](PFP)不能与吸附在氧化石墨烯(GO)表面的单链DNA结合的实验发现,借助GO对单链DNA和双链DNA作用力强度大小的差异,构建了一个背景信号低、灵敏度高的Exo I检测新方法。GO和PFP的最适浓度分别为2.5和7.2 mg/L。在最佳条件下,Exo I浓度在0.5~4.0 U/mL范围内与体系的荧光强度呈良好的线性关系,线性方程为F=-0.11c+0.861,检出限为0.16 U/mL。该方法可用于血清模拟样品中Exo I活性的检测,加标回收率为103.6%~106.0%。As an important ribozyme,exonuclease I(Exo I)engages in a serious of biological processes and has the capability to keep stabilized information of genetic.Therefore,it has great research value to establish an effective method to detect the Exo I activity.According to the finding that the polyfluorene-based fluorescent conjugated polymers-PFP cannot interact with single-stranded DNA adsorbed on graphene oxide(GO)surface,combining with the different binding force intensity of GO with single-stranded DNA and double-stranded,a novel method with low background and high sensitivity for sensing Exo I was constructed.The results showed the optimal concentrations of GO and PFP were 2.5 mg/L and 7.2 mg/L,respectively.Under the optimum conditions,the fluorescence intensity at 525 nm exhibited a good linearity with Exo I concentration in the range of 0.5~4.0 U/mL,where the linear equation was F=–0.11c+0.861,and the detection limit was 0.16 U/mL.The method was successfully used for the detection of Exo I in serum with recoveries of 103.6%~106.0%.

关 键 词：荧光共轭聚合物 氧化石墨烯 DNA 低背景 核酸外切酶I 

分 类 号：O657.3[理学—分析化学]