基于DNA的比色分析法快速测定尿液中的Hg^(2+)  

DNA-based Colorimetric Assay for Fast Detection of Mercury Ions in Urine

作　　者：赵秋伶[1] 刘玲玲[1] 杨丽娜[1] 张振宇[2] 

机构地区：[1]辽宁工程技术大学基础教学部,葫芦岛125105 [2]辽宁工程技术大学电子与信息工程学院,葫芦岛125105

出　　处：《分析化学》2014年第5期683-688,共6页Chinese Journal of Analytical Chemistry

摘　　要：以琼脂糖珠作为固定DNA的载体,建立了可视化的快速检测尿液中Hg2+的方法。DNA对Hg2+特异性识别后,其构象发生变化,启动相邻序列DNA酶的类过氧化物酶催化活性,进而催化氧化双氧水介导的ABTS(2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸))体系,溶液显绿色。考察了各种物质用量对检测体系的影响。在最优实验条件下,体系在420 nm处的吸光度与Hg2+浓度呈良好线性关系,线性范围为5~200 nmol/L,检出限为2 nmol/L。应用于真实尿样中Hg2+检测,加标回收率为95.1%~99.8%,相对标准偏差(n=5)为1.5%~3.1%。本方法对Hg2+具有良好的选择性,且检测不受其它金属离子干扰。另外,以琼脂糖珠为固相载体,能实现高效快速分离,有效排除尿液中其它物质对显色的影响,提高了检测的准确度和灵敏度。A novel colorimetric assay for the rapid detection of mercury ions in urine was established with agarose beads as carrier to capture DNA. Specific recognition of DNA towards mercury ions leads to conformational change and DNAzyme formation caused by DNA conformational change revealed peroxidase-like activities, catalyzing the H2 O2-mediated oxidation of 2, 2-azinobis （ 3-ethylbenzothiozoline ）-6-sulfonic acid （ ABTS） to produce green color. The effects of the amount of various substances on detection system were investigated. Under optimal conditions, the absorbances at 420 nm of the system showed a good linear relationship with the concentration of mercury ions ranged from 5 to 200 nmol/L, the detection limit was 2 nmol/L. When tested Hg2＋in real urine, the spiked recoveries were from 95. 1% to 99. 8% and the relative standard deviations （ n=5 ） were between 1 . 5% and 3 . 1%. This method had good selectivity for the detection of Hg2＋avoiding interference from other metal ions. Furthermore, the fast and efficient separation was achieved with agarose beads as a solid phase carrier to effectively exclude the influence of other materials in urine on the color leading to the detection accuracy and high sensitivity.

关 键 词：琼脂糖珠 脱氧核糖核酸 脱氧核糖核酸酶 比色分析 尿 Hg2+ 

分 类 号：R446.12[医药卫生—诊断学] O657.3[医药卫生—临床医学]