title: Folic acid functionalized silver nanoparticles with sensitivity and selectivity colorimetric and fluorescent detection for Hg2+ and efficient catalysis.
abstract: In this research, folic acid functionalized silver nanoparticles (FA-AgNPs) were selected as a colorimetric and a 'turn on' fluorescent sensor for detecting Hg(2+). After being added into Hg(2+), AgNPs can emit stable fluorescence at 440 nm when the excitation wavelength is selected at 275 nm. The absorbance and fluorescence of the FA-AgNPs could reflect the concentration of the Hg(2+) ions. Thus, we developed a simple, sensitive analytical method to detect Hg(2+) based on the colorimetric and fluorescence enhancement of FA-AgNPs. The sensor exhibits two linear response ranges between absorbance and fluorescence intensity with Hg(2+) concentration, respectively. Meanwhile, a detection limit of 1 nM is estimated based on the linear relationship between responses with a concentration of Hg(2+). The high specificity of Hg(2+) with FA-AgNPs interactions provided the excellent selectivity towards detecting Hg(2+) over other metal ions (Pb(2+), Mg(2+), Zn(2+), Ni(2+), Cu(2+), Co(2+), Ca(2+), Mn(2+), Fe(2+), Cd(2+), Ba(2+), Cr(6+) and Cr(3+)). This will provide a simple, effective and multifunctional colorimetric and fluorescent sensor for on-site and real-time Hg(2+) ion detection. The proposed method can be applied to the analysis of trace Hg(2+) in lake water. Additionally, the FA-AgNPs can be used as efficient catalyst for the reduction of 4-nitrophenol and potassium hexacyanoferrate (III).
authors.affiliation: Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, Harbin Normal University, 150025, People's Republic of China.
authors.forename: Dongyue
authors.initials: D
authors.lastname: Su
authors.forename: Xin
authors.initials: X
authors.lastname: Yang
authors.forename: Qingdong
authors.initials: Q
authors.lastname: Xia
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Fang
authors.initials: F
authors.lastname: Chai
authors.forename: Chungang
authors.initials: C
authors.lastname: Wang
authors.forename: Fengyu
authors.initials: F
authors.lastname: Qu
mesh_terms: D002384:Catalysis; D003124:Colorimetry / Q000379:methods; D004396:Coloring Agents / Q000737:chemistry*; D005292:Ferricyanides / Q000737:chemistry; D005453:Fluorescence; D005492:Folic Acid / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D008628:Mercury / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009596:Nitrophenols / Q000737:chemistry; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; D005292:Ferricyanides; D009596:Nitrophenols; D012834:Silver; D006046:Gold; D005492:Folic Acid; D008628:Mercury; C028033:potassium ferricyanide; C024836:4-nitrophenol