Highly Sensitive Fluorometric Hg^2＋ Biosensor with a Mercury（Ⅱ）-Specific Oligonucleotide （MSO） Probe and Water-Soluble Graphene Oxide （WSGO）  

作　　者：刘兴奋 苗丽坤 蒋旭 马延文 范曲立 黄维 

机构地区：[1]Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute of Advanced Materials (IAM)and School of Materials Science and Engineering, Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210046, China

出　　处：《Chinese Journal of Chemistry》2011年第5期1031-1035,共5页中国化学（英文版）

基　　金：Project supported by the National 973 Project （No. 2009CB930601）, and the National Natural Science Foundation ot Claina （Nos. 20874048, 20903057, 21005040）, and the Natural Science Foundation of Jiangsu Province （No. BK2008452）.

摘　　要：A highly sensitive and selective, ＂turn-on＂ and simple Hg2＋ biosensor is reported by using water-soluble graphene oxide （WSGO） and dye-labeled mercury（Ⅱ）-specific oligonucleotide （MSO） probe. The probe is rich of thymine （T） and can readily form the stem-loop structure which consists of the T-HgZ＋-T configuration. In the absence of Hg2＋, the probe exists as a random coil conformation which can be readily adsorbed on the surface of WSGO by strong noncovalent binding of bases, as a result, the fluorescence of the dye labeled on the terminus of the MSO is strongly quenched by the efficient electron/energy transfer from the dye to WSGO. Upon addition of Hg^2＋, the formation of the T-Hg2＋-T structure releases the MSO from the surface of WSGO, resulting in a restora- tion of the fluorescence of dye-labeled MSO probe. Based on this observation, a highly sensitive and selective Hg2~ sensor is developed, which can work with ＂turn-on＂ mode in aqueous solutions at room temperature. By using the fluorometric method, the limit of detection for Hg2＋ can reach picomolar range （187 pmol·L^-1）, and it is demonstrated that the biosensor is highly selective and only minimally perturbed by a wide range of non-specific metalion.A highly sensitive and selective, ＂turn-on＂ and simple Hg2＋ biosensor is reported by using water-soluble graphene oxide （WSGO） and dye-labeled mercury（Ⅱ）-specific oligonucleotide （MSO） probe. The probe is rich of thymine （T） and can readily form the stem-loop structure which consists of the T-HgZ＋-T configuration. In the absence of Hg2＋, the probe exists as a random coil conformation which can be readily adsorbed on the surface of WSGO by strong noncovalent binding of bases, as a result, the fluorescence of the dye labeled on the terminus of the MSO is strongly quenched by the efficient electron/energy transfer from the dye to WSGO. Upon addition of Hg^2＋, the formation of the T-Hg2＋-T structure releases the MSO from the surface of WSGO, resulting in a restora- tion of the fluorescence of dye-labeled MSO probe. Based on this observation, a highly sensitive and selective Hg2~ sensor is developed, which can work with ＂turn-on＂ mode in aqueous solutions at room temperature. By using the fluorometric method, the limit of detection for Hg2＋ can reach picomolar range （187 pmol·L^-1）, and it is demonstrated that the biosensor is highly selective and only minimally perturbed by a wide range of non-specific metalion.

关 键 词：BIOSENSOR MERCURY graphene fluorescence 

分 类 号：O613.71[理学—无机化学] TP212.3[理学—化学]