title: Visual determination of trace cysteine based on promoted corrosion of triangular silver nanoplates by sodium thiosulfate.
abstract: In this study, triangular silver nanoplates (TAg-NPs) were used to detect trace Cysteine concentration in the presence of sodium thiosulfate (Na2S2O3). Study showed that the TAg-NPs could be gently etched by Cysteine with the concentration of 1.0×10(-7) mol L(-1) through forming Ag-S covalent bond at the three corners. However, in the presence of Na2S2O3 (only 3.0×10(-6) mol L(-1)), the corrosion of Cysteine on TAg-NPs can be promoted significantly. It was also found that the color, morphology, and the maximum absorption wavelength of TAg-NPs change clearly with the concentrations of Cysteine as low as 2.5×10(-8) mol L(-1). Furthermore, the wavelength shift values (Δλ) of TAg-NPs solution were proportional to the concentrations of Cysteine in the range of 1.0×10(-9)-1.0×10(-7) mol L(-1), and the linear regression equation is Δλ=-0.89+319.94 c (c, μM, n=5) with the correlation coefficient of 0.990. At the same time, the color change of the TAg-NPs solution could be observed clearly by the naked eyes with increasing Cysteine concentrations in the range of 2.5×10(-8)-1.0×10(-7) mol L(-1). Thus, a novel method for the detection of Cysteine by either UV-vis spectrophotometry detection or naked eyes observation is established. It allows determination of Cysteine content in compound amino acid injection sample of 18AA-V.
authors.affiliation: Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education of China, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China.
authors.forename: Xin Yan
authors.initials: XY
authors.lastname: Hou
authors.affiliation: Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education of China, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Chen
authors.affiliation: Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education of China, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Tang
authors.affiliation: Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education of China, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China. Electronic address: l_yunfei927@163.com.
authors.forename: Yun Fei
authors.initials: YF
authors.lastname: Long
mesh_terms: D000042:Absorption; D003343:Corrosion; D003545:Cysteine / Q000032:analysis*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D012834:Silver / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013885:Thiosulfates / Q000737:chemistry*
chemical_list: D013885:Thiosulfates; D012834:Silver; C017717:sodium thiosulfate; D003545:Cysteine
keywords: Absorption spectrum; Cysteine; Sodium thiosulfate; Triangular silver nanoplates