聚胸腺嘧啶-铜纳米簇/适体-金纳米粒子荧光探针用于微囊藻毒素-LR传感分析  

Fluorescent Probe for Detection of Microcystin-LR Based on Poly(thymidine)-Copper Nanoclusters and Aptamer-Gold Nanoparticles

作　　者：蒙化 阿华英 罗平馨 张艳丽[1] 高连训 王红斌[1] 杨文荣 庞鹏飞[1] MENG Hua;A Huaying;LUO Pingxin;ZHANG Yanli;GAO Lianxun;WANG Hongbin;YANG Wenrong;PANG Pengfei(Functional Nanomaterial-based Chemical and Biological Sensing Technology Innovation Team of Department of Education of Yunnan Province,Yunnan Minzu University,Kunming 650504,China;School of Life and Environmental Sciences,Deakin University,Geelong 3217,Australia)

机构地区：[1]云南民族大学云南省教育厅功能纳米材料基化学生物传感科技创新团队,昆明650504 [2]迪肯大学生命与环境科学学院,澳大利亚吉朗3217

出　　处：《高等学校化学学报》2025年第5期11-18,共8页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:21565031,21665027);云南省科技厅基础研究计划项目(批准号:202001AT070012);云南民族大学研究生科研创新基金(批准号:2024SKY135)资助.

摘　　要：采用DNA模板法合成了聚胸腺嘧啶-铜纳米簇[poly(T)-CuNCs]/适体-金纳米粒子(aptamer-AuNPs)荧光探针,用于微囊藻毒素-LR(MC-LR)的高灵敏传感检测.设计了3条DNA核苷酸链:MC-LR适体链(aptamer)和2条聚胸腺嘧啶单链DNA[poly(T)S 1和(poly(T)S 2].以poly(T)S 1和poly(T)S 2为模板,利用抗坏血酸(AA)还原Cu^(2+),合成了具有粉红色荧光的poly(T)S 1-CuNCs和poly(T)S 2-CuNCs.两端巯基标记的aptamer通过Au-S键与AuNPs相连形成AuNPs-aptamer-AuNPs共轭物,后者与poly(T)-CuNCs杂交形成dsDNA-CuNCs,双链结构中CuNCs与AuNPs之间由于荧光共振能量转移(FRET)导致体系荧光猝灭.加入目标物MC-LR后,MC-LR会与dsDNA-CuNCs中的aptamer特异性结合,引起双链结构解体,poly(T)-CuNCs释放至溶液中,体系荧光得以恢复.基于此,构建了一种“off-on”型荧光探针用于MC-LR检测,该方法对MC-LR的线性范围为1 ng/L~500μg/L,检出限为0.3 ng/L(S/N=3).Poly(T)-CuNCs/aptamer-AuNPs荧光适体探针制备简单、选择性高,可用于实际水样中MC-LR定量分析.A fluorescent probe of poly(thymidine)-copper nanoclusters/aptamer-gold nanoparticles(poly(T)-CuNCs/aptamer-AuNPs)was constructed for highly sensitive sensing detection of microcystin-LR(MC-LR)using DNA template method.Three DNA nucleotides were designed,including MC-LR aptamer,and two poly(thymidine)ssDNA(poly(T)S 1 and poly(T)S 2).Using poly(T)S 1 and poly(T)S 2 as templates,poly(T)S 1-CuNCs and poly(T)S 2-CuNCs with pink fluorescence were synthesized by reducting Cu^(2+)with ascorbic acid(AA).Aptamer labeled with thiol groups at two both ends were linked with AuNPs through Au-S bonds to form AuNPs-aptamer-AuNPs bioconjugates.AuNPs-aptamer-AuNPs hybridized with poly(T)-CuNCs to form dsDNA-CuNCs.Fluorescence resonance energy transfer(FRET)occurred between CuNCs and AuNPs in the dsDNA-CuNCs structure,leading to fluorescence quenching of dsDNA-CuNCs.In the presence of target MC-LR,MC-LR specifically bonded with aptamer in dsDNA-CuNCs,resulting in the dissociation of dsDNA structure.The poly(T)-CuNCs were released into the solution,restoring the system's fluorescence.An"off-on"type of fluorescent probe was constructed for the detection of MC-LR.The linear range for MC-LR detection is 1 ng/L-500μg/L,with a detection limit of 0.3 ng/L(S/N=3).The proposed fluorescent aptamer probe possesses the advantages of simple preparation,high selectivity,and can be applied for quantitative detection and analysis of MC-LR in real water samples.

关 键 词：微囊藻毒素-LR 聚胸腺嘧啶-铜纳米簇 适体-金纳米粒子 荧光探针 

分 类 号：O657.3[理学—分析化学]