title: Trifunctional molecular beacon-mediated quadratic amplification for highly sensitive and rapid detection of mercury(II) ion with tunable dynamic range.
abstract: Analyses of target with low abundance or concentration varying over many orders of magnitude are severe challenges faced by numerous assay methods due to their modest sensitivity and limited dynamic range. Here, we introduce a homogeneous and rapid quadratic polynomial amplification strategy through rational design of a trifunctional molecular beacon, which serves as not only a reporter molecule but also a bridge to couple two stage amplification modules without adding any reaction components or process other than basic linear amplification. As a test bed for our studies, we took mercury(II) ion as an example and obtained a high sensitivity with detection limit down to 200 pM within 30min. In order to create a tunable dynamic range, homotropic allostery is employed to modulate the target specific binding. When the number of metal binding site varies from 1 to 3, signal response is programmed accordingly with useful dynamic range spanning 50, 25 and 10 folds, respectively. Furthermore, the applicability of the proposed method in river water and biological samples are successfully verified with good recovery and reproducibility, indicating considerable potential for its practicality in complex real samples.
authors: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049 PR China.
authors: Yue
authors: Y
authors: Zhao
authors: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049 PR China.
authors: Huaqing
authors: H
authors: Liu
authors: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049 PR China.
authors: Feng
authors: F
authors: Chen
authors: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049 PR China.
authors: Min
authors: M
authors: Bai
authors: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049 PR China. Electronic address: nanoptzhao@163.com.
authors: Junwu
authors: J
authors: Zhao
authors: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049 PR China. Electronic address: yxzhao@mail.xjtu.edu.cn.
authors: Yongxi
authors: Y
authors: Zhao
mesh_terms: D015342:DNA Probes / Q000737:chemistry* / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008628:Mercury / Q000032:analysis*; D008856:Microscopy, Fluorescence / Q000379:methods*; D015336:Molecular Probe Techniques; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D015342:DNA Probes; D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Mercury(II) ion; Quadratic amplification; Trifunctional molecular beacon; Tunable dynamic range