基于功能化双链DNA复合纳米结构的荧光适体传感器  

Fluorescent aptamer sensors based on functionalized double-stranded DNA composite nanostructures

作　　者：任林娇 刘玉鑫 陈高凯 马世林 张培 秦自瑞 姜利英 REN Linjiao;LIU Yuxin;CHEN Gaokai;MA Shilin;ZHANG Pei;QIN Zirui;JIANG Liying(College of Electrical and Information,Zhengzhou University of Light Industry,Zhengzhou 450002,China;College of Electronics and Information,Zhengzhou University of Light Industry,Zhengzhou 450002,China;Academy for Quantum Science and Technology,Zhengzhou University of Light Industry,Zhengzhou 450002,China)

机构地区：[1]郑州轻工业大学电气信息工程学院,郑州450002 [2]郑州轻工业大学电子信息学院,郑州450002 [3]郑州轻工业大学量子科技研究院,郑州450002

出　　处：《分析试验室》2024年第9期1243-1251,共9页Chinese Journal of Analysis Laboratory

基　　金：国家自然科学基金项目(62073299,12004348,61801436);中原科技创新领军人才项目(224200510026);河南省科技攻关项目(232102220008,212102210196,212102210278,212102210002)资助。

摘　　要：针对生化及临床检测分析中生物小分子浓度低、变化范围大等特点,基于功能化双链DNA复合纳米结构,构建了一种宽范围、低检出限的荧光传感检测方法。功能化双链DNA由3’端含有多个碱基T的核酸适体(PolyTn-Apt)和5’端修饰FAM荧光基团的互补链(cDNA@FAM)构成,在纳米金(AuNPs)表面修饰该功能化双链DNA,由于荧光共振能量转移作用,FAM荧光处于猝灭状态;加入被测物后,核酸适体与被测物结合,双链被打开,FAM远离AuNPs,荧光恢复。碱基T的存在可使AuNPs结合更多的双链结构,扩大其传感检测范围。结果表明:以该方法制备的三磷酸腺苷(ATP)传感器,检测范围可达1 nmol/L~100μmol/L,跨5个数量级,检出限为0.41 nmol/L,且特异性明显;以该方法制备的氨苄西林(AMP)传感器,检测范围可达1 nmol/L~50μmol/L,跨4个数量级,检出限为0.42 nmol/L,且特异性突出。该方法具有一定的普适性,通过置换核酸适体种类,有望对多种生物小分子实现宽范围、低检出限的定量检测。A fluorescence sensing assay with a wide range and low detection limit was constructed based on a functionalized double-stranded DNA composite nanostructure for biochemical and clinical assay analysis with a low concentration and wide variation range.Functional double-stranded DNA was composed of a PolyTn-Apt containing multiple T base at the 3′end and a complementary chain(cDNA@FAM)modifying FAM at the 5′end.When the functionalized double-stranded DNA was modified on the surface of gold nanoparticles(AuNPs),the FAM fluorescence was in a quenching state because of fluorescence resonance energy transfer.Upon the addition of the analyte,the nucleic acid aptamer binds to the test substance,then the double strand is opened,leading to the FAM moving away from the AuNPs and fluorescence restoration.The presence of T base could make the AuNPs bind more double-stranded structures and increase the sensing detection range.The experimental results showed that the detection range of the adenosine triphosphate(ATP)sensor prepared by this method could reach 1 nmol/L-100μmol/L,spanning 5 orders of magnitude,and the detection limit was 0.41 nmol/L,with obvious specificity;the detection range of the ampicillin(AMP)sensor prepared by this method could reach 1 nmol/L-50μmol/L,spanning 4 orders of magnitude,and the detection limit was 0.42 nmol/L,with outstanding specificity.Therefore,this method had certain universality and was expected to achieve a wide range and low detection limit for the quantitative detection of various biological small molecules by replacing nucleic acid aptamers.

关 键 词：功能化双链DNA 荧光传感器 宽范围 三磷酸腺苷 氨苄西林 

分 类 号：O657.3[理学—分析化学]