摘要
以新型环状DNA为模板,制备了环状DNA-银纳米簇(Circular DNA-AgNCs)荧光探针,构建了一种无酶无标记检测微囊藻毒素-LR(MC-LR)的荧光传感分析方法.设计的环状DNA由MC-LR适体链(Apt)和适体链的互补链(cDNA)杂交形成,且cDNA可作为DNA模板用于合成AgNCs.利用透射电子显微镜(TEM)、紫外-可见光谱(UV-Vis)和荧光光谱(FL)表征了AgNCs的形貌和光学特性.结果表明,当存在目标物MC-LR时,由于MC-LR与环状DNA中Apt高特异性和高亲和力结合,导致环状DNA解体,释放出的cDNA-AgNCs在610 nm处呈现强荧光.在优化实验条件下,环状DNA-AgNCs荧光探针对MC-LR检测的线性范围为0.005~500μg/L,检出限为1.7 ng/L(S/N=3).该荧光探针具有制备简单、无需任何标记和灵敏度高等特点,为环境水样中微囊藻毒素-LR的快速和准确测定提供了一种简单、可靠和有效的方法.
An enzyme-free and label-free fluorescence sensing method for detection of Microcystin-LR(MC-LR)was developed based on circular DNA-silver nanoclusters(circular DNA-AgNCs)fluorescent probe,which was prepared by using circular DNA as template.The circular DNA was composed of MC-LR aptamer(Apt)and aptamer complementary(cDNA),which can be used as DNA template to synthesize AgNCs.The morphology and optical properties of prepared circular DNA-AgNCs were characterized by transmission elec⁃tron microscope(TEM),ultraviolet⁃visible spectroscopy(UV-Vis)and fluorescent spectroscopy(FL).The ex⁃perimental results showed that the circular DNA is dissociated due to the high specificity and affinity between Apt of circular DNA and MC-LR in the presence of object MC-LR,resulting in the releasing of cDNA-AgNCs with an enhanced fluorescent intensity at 610 nm.Under the optimized experimental conditions,the linear range of circular DNA-AgNCs fluorescent probe for MC-LR determination is 0.005-500μg/L with a detection limit of 1.7 ng/L(S/N=3).The developed fluorescent probe has the advantages of simple preparation,no labe-ling and high sensitivity,providing a simple,reliable and effective method for the determination of Microcys⁃tin-LR in practical environmental water samples.
作者
杨新杰
赖艳琼
李秋旸
张艳丽
王红斌
庞鹏飞
杨文荣
YANG Xinjie;LAI Yanqiong;LI Qiuyang;ZHANG Yanli;WANG Hongbin;PANG Pengfei;YANG Wenrong(National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials,Yunnan Minzu University,Kunming 650500,China;School of Life and Environmental Sciences,Deakin University,Geelong 3217,Australia)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第12期3600-3605,共6页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21565031,21665027)
云南省科技厅应用基础研究基金(批准号:202001AT070012)资助.
