title: Oligonucleotide-based fluorogenic sensor for simultaneous detection of heavy metal ions.
abstract: In this study, we report a new fluorogenic sensor based on fluorescence resonance energy transfer (FRET) for detection of heavy metal ions in aqueous solution. The method showed the advantage of being simple, highly sensitive and selective, and rapid. The donor (CdTe QDs) and acceptor (TAMRA or Cy5) are brought into close proximity to one another due to Hg(2+) and Ag(+) form strong and stable T-Hg(2+)-T complexes and C-Ag(+)-C complexes, which quenches the fluorescent intensity of CdTe QDs and enables the energy transfer from donor to acceptor. This sensor showed high sensitivity and selectivity when only one kind of ion (Ag(+) or Hg(2+)) exists. Furthermore, the assay can also simultaneously detect Ag(+) and Hg(2+) in water media with the limit of detection (LOD) of 2.5 and 1.8 nM, separately, which satisfactorily meets the sensitivity demands of Environmental Protection Agency (EPA) and World Health Organization (WHO). This assay also exhibits excellent selectivity toward Ag(+) and Hg(2+). Therefore, this method is of great practical and theoretical importance for detecting heavy metal ions in aqueous solution.
authors.affiliation: School of Food Science & Technology, State Key Laboratory of Food Science & Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Changlong
authors.initials: C
authors.lastname: Hao
authors.forename: Liguang
authors.initials: L
authors.lastname: Xua
authors.forename: Changrui
authors.initials: C
authors.lastname: Xing
authors.forename: Hua
authors.initials: H
authors.lastname: Kuang
authors.forename: Libing
authors.initials: L
authors.lastname: Wang
authors.forename: Chuanlai
authors.initials: C
authors.lastname: Xu
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D019187:Cadmium Compounds / Q000737:chemistry; D005453:Fluorescence; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis*; D045663:Quantum Dots; D012235:Rhodamines / Q000737:chemistry; D012680:Sensitivity and Specificity; D012834:Silver / Q000032:analysis*; D013691:Tellurium / Q000737:chemistry; D014867:Water / Q000032:analysis*
chemical_list: C114557:5-carboxytetramethylrhodamine succinimidyl ester; D019187:Cadmium Compounds; D012235:Rhodamines; D014867:Water; D012834:Silver; D008628:Mercury; D013691:Tellurium; C028337:cadmium telluride