基于C-Ag^+-C配位作用及核酸三链体系的表面增强拉曼光谱法快速检测银  

New strategy for rapid determination of silver(Ⅰ) ions by SERS based on C-Ag^+-C and triplex DNA system

作　　者：聂钰洪[1] 张蓓[1] 周晓微[1] 赵凌国 

机构地区：[1]郑州轻工业学院食品与生物工程学院,郑州450002 [2]深圳市宝安区疾病预防与控制中心,深圳518100

出　　处：《分析试验室》2016年第7期813-817,共5页Chinese Journal of Analysis Laboratory

基　　金：广东省自然科学基金(2015A030310454);深圳市科技项目(JCYJ20140414100411116);郑州轻工业学院校基金(2014XJJ006)项目资助

摘　　要：建立了一种基于C-Ag^+-C配位作用和核酸三链体系的表面增强拉曼光谱方法以快速检测Ag^+。单链DNA(ssDNA)能够分散和稳定修饰有罗丹明6G的金纳米颗粒。当加入Ag^+后,该富含胞嘧啶(C)的ssDNA通过Ag^+配位作用与dsDNA形成具有刚性结构的三链DNA(tsDNA),tsDNA无法稳定金纳米颗粒,致使其发生团聚而产生R6G的拉曼信号峰,实现检测Ag^+的目的。实验对制备的金纳米颗粒进行了表征,并考察了DNA浓度对金纳米颗粒稳定性的影响。结果显示,在优化的条件下,相比于其它11种金属离子,本法对Ag^+具有较强的选择性。在1~10μmol/L范围内,拉曼峰强度和Ag^+浓度的线性关系良好,相关系数R为0.9988。方法适用于Ag^+的快速分析。A method for rapid determination of silver ions was established by surface enhanced Raman spectroscope（ SERS） based on C- Ag^＋- C interaction and triplex DNA system. The ss DNA could stabilize the gold nanoparticles which were modified by rhodamine 6G（ R6G）. However,after silver ions were added,the ds DNA formed triple strand DNA（ tsDNA） with the cytosine（ C） riched ss DNA. The consequential ts DNA could not stabilize the gold nanoparticles like the ssDNA. Thus the gold nanoparticles aggregated to form ＂ Hot Spots＂ and generate the Raman signal of R6 G. The morphology of gold nanoparticles was characterized systematically by UVvisible and TEM. Furthermore,the influence of DNA concentration on the stabilization of gold nanoparticles was also investigated. Under optimal conditions,high selectivity for silver ions was achieved compared with 11 other metal ions. Good linearity was also found between the concentration of silver ions and Raman signal within the range of 1 ～ 10 μmol / L,and the R was 0. 9988. This method is fast,simple,precise and feasible for the determination of silver ions.

关 键 词：表面增强拉曼光谱 金纳米颗粒 DNA 银离子 

分 类 号：O657.3[理学—分析化学]