title: Terbium(III)/gold nanocluster conjugates: the development of a novel ratiometric fluorescent probe for mercury(II) and a paper-based visual sensor.
abstract: In this work, a novel ratiometric fluorescent probe was developed for rapid, highly accurate, sensitive and selective detection of mercury(II) (Hg(2+)) based on terbium(III)/gold nanocluster conjugates (Tb(3+)/BSA-AuNCs), in which bovine serum albumin capped gold nanoclusters (BSA-AuNCs) acted as the signal indicator and terbium(III) (Tb(3+)) was used as the build-in reference. Our proposed ratiometric fluorescent probe exhibited unique specificity toward Hg(2+) against other common environmentally and biologically important metal ions, and had high accuracy and sensitivity with a low detection limit of 1 nM. In addition, our proposed probe was effectively employed to detect Hg(2+) in the biological samples from the artificial Hg(2+)-infected rats. More significantly, an appealing paper-based visual sensor for Hg(2+) was designed by using filter paper embedded with Tb(3+)/BSA-AuNC conjugates, and we have further demonstrated its feasibility for facile fluorescent sensing of Hg(2+) in a visual format, in which only a handheld UV lamp is used. In the presence of Hg(2+), the paper-based visual sensor, illuminated by a handheld UV lamp, would undergo a distinct fluorescence color change from red to green, which can be readily observed with naked eyes even in trace Hg(2+) concentrations. The Tb(3+)/BSA-AuNC-derived paper-based visual sensor is cost-effective, portable, disposable and easy-to-use. This work unveiled a facile approach for accurate, sensitive and selective measuring of Hg(2+) with self-calibration.
authors.affiliation: Department of Chemistry, School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China. mzhang@chem.ecnu.edu.cn.
authors.forename: Yan-Xia
authors.initials: YX
authors.lastname: Qi
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Anwei
authors.initials: A
authors.lastname: Zhu
authors.forename: Guoyue
authors.initials: G
authors.lastname: Shi
mesh_terms: D000818:Animals; D002417:Cattle; D005456:Fluorescent Dyes / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D057230:Limit of Detection; D008628:Mercury / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010209:Paper; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013725:Terbium / Q000737:chemistry*; D013997:Time Factors
chemical_list: D005456:Fluorescent Dyes; D013725:Terbium; D012710:Serum Albumin, Bovine; D006046:Gold; D008628:Mercury