title: Facile Colorimetric Detection of Silver Ions with Picomolar Sensitivity.
abstract: Although various colorimetric methods have been actively developed for the detection of Ag+ions because of their simplicity and reliability, the limits of detection of these methods are confined to the nanomolar (nM) level. Here, we demonstrate a novel strategy for colorimetric Ag+detection with picomolar (pM) sensitivity. This strategy involves the use of poly(vinylpyrrolidone)- (PVP-) capped Pt nanocubes as artificial peroxidases that can effectively generate a colored signal by catalyzing the oxidation of peroxidase substrates. In the presence of Ag+ions, the colored signal generated by these Pt cubes is greatly diminished because of the specific and efficient inhibition of Ag+toward the peroxidase-like activity of the Pt cubes. This colorimetric method can achieve an ultralow detection limit of 80 pM and a wide dynamic range of 10-2-104nM. To the best of our knowledge, the method presented in this work shows the highest sensitivity for Ag+detection among all reported colorimetric methods. Moreover, this method also features simplicity and rapidness as it can be conducted at room temperature, in aqueous solution, and requires only ∼6 min.
authors.affiliation: Department of Chemistry, Michigan Technological University , Houghton, Michigan 49931, United States.|Key Laboratory of Analysis and Detection for Food Safety (Fujian Province & Ministry of Education), Collaborative Innovation Center of Detection Technology for Haixi Food Safety and Products (Fujian Province), Department of Chemistry, Fuzhou University , Fuzhou 350108, People's Republic of China.
authors.forename: Zhuangqiang
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Houghton High School , Houghton, Michigan 49931, United States.
authors.forename: Grace G
authors.initials: GG
authors.lastname: Liu
authors.affiliation: Department of Chemistry, Michigan Technological University , Houghton, Michigan 49931, United States.
authors.forename: Haihang
authors.initials: H
authors.lastname: Ye
authors.affiliation: Department of Chemistry, Michigan Technological University , Houghton, Michigan 49931, United States.
authors.forename: Robert
authors.initials: R
authors.lastname: Rauschendorfer
authors.affiliation: Key Laboratory of Analysis and Detection for Food Safety (Fujian Province & Ministry of Education), Collaborative Innovation Center of Detection Technology for Haixi Food Safety and Products (Fujian Province), Department of Chemistry, Fuzhou University , Fuzhou 350108, People's Republic of China.
authors.forename: Dianping
authors.identifier: 0000-0002-0134-3983
authors.initials: D
authors.lastname: Tang
authors.affiliation: Department of Chemistry, Michigan Technological University , Houghton, Michigan 49931, United States.
authors.forename: Xiaohu
authors.identifier: 0000-0002-6372-7712
authors.initials: X
authors.lastname: Xia