title: Electrochemical impedance spectroscopy sensor for ascorbic acid based on copper(I) catalyzed click chemistry.
abstract: Copper(I) species can be acquired from the reduction of copper(II) by ascorbic acid (AA) in situ, and which in turn quantitative catalyze the azides and alkynes cycloaddition reaction. In this study, propargyl-functionalized ferrocene (propargyl-functionalized Fc) has been modified on the electrode through reacting with azide terminal modified Au electrode via copper(I) catalyzed azides and alkynes cycloaddition (CuAAC) reaction. The electrochemical impedance spectroscopy (EIS) measurement has been applied to test the electron transfer resistance of the Au electrode before and after click reaction. The changes of the fractional surface coverage (θ) with different AA concentrations are characterized. It is found that the θ value has a linear response to the logarithm of AA concentration in the range of 5.0 pmol/L to 1.0 nmol/L with the detection limits of 2.6 pmol/L. The sensor shows a good stability and selectivity. And it has been successfully applied to the AA detection in the real samples (urine) with satisfactory results.
authors: MOE Key Laboratory of Analysis and Detection for Food Safety, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002, China.
authors: Suyan
authors: S
authors: Qiu
authors: Sen
authors: S
authors: Gao
authors: Qida
authors: Q
authors: Liu
authors: Zhenyu
authors: Z
authors: Lin
authors: Bin
authors: B
authors: Qiu
authors: Guonan
authors: G
authors: Chen