摘要
利用银离子(Ag~+)可与DNA中胞嘧啶碱基(C)相互作用的性质, 构建了一种用于检测Ag~+的比率型电化学传感器. 以铬金属有机骨架材料(Cr-MIL-101 NH_(2))标记的单链DNA作为信号探针(Cr-MOFs-SP), 电解质溶液的二茂铁甲酸作为内部参考探针(Fc-RP), 在Ag~+存在的情况下, 可以检测到 Cr-MOFs 的信号 . 同时, 二茂铁甲酸的信号几乎保持稳定, 因此, Ag~+浓度可以通过I_(Cr-MOFs-SP)/I_(Fc- RP)的比率响应进行监测. 所制备的比率型生物传感器可有效消除外界环境影响和避免电化学背景信号, 提高了检测的重现性、准确性和灵敏度. 具有三维结构的DNA四面体纳米材料(NTH)可有效消除DNA的非特异性吸附. 同时, 所设计的DNA NTH增强了机械刚度, 可以增加Ag~+的捕获量和信号物质的负载量, 进一步提高了检测灵敏度. 该比率型生物传感器对Ag~+的检测具有良好的选择性、较宽的线性范围(0.1~100 nmol/L)和较低的检出限(33 pmol/L). 将此传感器用于滇池水样中Ag~+的含量测定, 回收率为96.8%~103.0%, 表明此传感器具有潜在的实际应用前景.
A ratiometric electrochemical sensor for detecting silver ion(Ag^(+))is proposed. Single-stranded DNA labeled with chromium metal organic framework(Cr-MIL-101 NH_(2))is used as a signal probe(Cr-MOFs-SP),and ferrocene formic acid in the electrolyte solution is used as an internal reference probe(Fc-RP). In the presence of Ag^(+),the signal of Cr-MOFs can be detected. At the same time,the signal of ferrocene formic acid remained stable. Therefore,the Ag^(+) concentration can be monitored by the ratiometric response of I_(Cr-MOFs-SP)/I_(Fc-RP). The proposed ratiometric biosensor can effectively eliminate the influence of the external environment and avoid electrochemical background signals,also improve the reproducibility,accuracy and sensitivity of detection. The DNA tetrahedral nanomaterials(NTH)with a three-dimensional structure can effectively eliminate the non-specific adsorption of DNA. The well-designed DNA NTH enhances mechanical rigidity,can increase the capture amount of Ag^(+) and the load of signal substances,and further improve the detection sensitivity. This ratiometric biosensor has a good selectivity for Ag^(+) detection,a wide linear range(0.1-100 nmol/L)and a low detection limit(33 pmol/L). This sensor has been used for the determination of Ag^(+) content in Dianchi Lake water samples with the recovery rate of 96.8%-103.0%, which shows that this sensor has potential practical application prospects.
作者
李玉龙
谢发婷
管燕
刘嘉丽
张贵群
姚超
杨通
杨云慧
胡蓉
LI Yulong;XIE Fating;GUAN Yan;LIU Jiali;ZHANG Guiqun;YAO Chao;YANG Tong;YANG Yunhui;HU Rong(School of Chemistry and Chemical Engineering,Yunnan Normal University,Kunming 650500,China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2022年第8期248-258,共11页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21864026,21605130)资助。
关键词
银离子
电化学传感器
比率型
四面体
金属有机骨架材料
Silver ion
Electrochemical sensor
Ratiometric type
Tetrahedron
Metal organic framework material
