DNA碱基与高氯酸根共吸附行为的表面增强拉曼光谱研究  

Surface-Enhanced Raman Spectroscopic Study on the Co-adsorption of DNA Bases with Perchlorate

作　　者：崔丽[1] 任斌[2] 田中群[2] 

机构地区：[1]中国科学院城市环境研究所,福建厦门361021 [2]厦门大学化学化工学院化学系,固体表面物理化学国家重点实验室,福建厦门361005

出　　处：《物理化学学报》2010年第2期397-402,共6页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(20673086,20620130427,20825313);福建省自然科学基金(2009J05032)资助项目~~

摘　　要：共吸附有助于实现弱吸附分子或离子的高灵敏表面增强拉曼光谱(SERS)检测.本文研究了四种脱氧核糖核酸(DNA)碱基,即腺嘌呤、鸟嘌呤、胞嘧啶、胸腺嘧啶与高氯酸根(ClO4-)在金纳米粒子表面的共吸附行为,并考察了吸附能力、电位、共存阴离子等因素的影响.研究发现四种碱基在质子化后都可以与ClO4-发生共吸附,但在金表面吸附能力弱的胸腺嘧啶与ClO4-共吸附所获得的ClO4-信号最弱.另外,负电位下电极的排斥作用,以及较正电位下基底SERS增强效应减小等因素都会导致ClO4-信号衰减.此外,Cl-、NO3-、SO24-等阴离子可以与ClO4-发生可逆动态竞争共吸附,同时引起ClO4-信号减弱.以上结果将为提高共吸附法检测弱吸附离子的灵敏度提供重要参考.Co-adsorption with molecules that strongly adsorb on metallic surfaces is beneficial in improving the surface- enhanced Raman spectroscopy （SERS） detection sensitivity of some weakly adsorbed molecules or ions. In this paper, the co-adsorption of four deoxyribonucleic acid （DNA） bases： adenine, guanine, cytosine, and thymine with CIO1^- was studied. Factors like adsorption ability, applied potentials, and coexisting anions were examined to illustrate how they affect co-adsorption. We found that the four DNA bases in their protonated forms could co-adsorb with CIO4^- Among them, thymine with the weakest adsorption ability on Au showed the weakest co-adsorption ability with CIO4^- In addition, repulsion from both negative potentials and reduced SERS enhancements of Au substrates at relatively positive potentials led to a decrease in the SERS intensity of CIO4^- Moreover, anions such as CI^-, NO3^- and SO4^2- were shown to influence the co-adsorption of C10; with adenine based on a dynamic and reversible competitive co-adsorption process. The above results are very helpful in optimizing the SERS detection sensitivity of weakly adsorbed ions or molecules via the co-adsorption method.

关 键 词：共吸附 表面增强拉曼光谱 DNA碱基 高氯酸根 

分 类 号：O647.31[理学—物理化学]