A Label-free Immunosensor Based on K₃[Fe(CN)₆] and Aldehyde-Functionalized Pyridinium

Authors

Xia HU, College of Chemistry and Material Engineering, Hunan University of Arts and Science, Changde 415000, Hunan，China;
You-ming SHEN, College of Chemistry and Material Engineering, Hunan University of Arts and Science, Changde 415000, Hunan，China;
Guang-yu SHEN, School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620;Follow

Corresponding Author

Guang-yu SHEN(sgyrab@163.com)

Abstract

A novel aldehyde-functionalized pyridinium was successfully synthesized. Using K₃[Fe(CN)₆] as a redox species modified on the surface of the electrode through Poly(diallyldimethylammonium chloride), we developed a label-free immunosensor based on aldehyde-functionalized pyridinium that was applied to simplify antibody immobilization on the electrode surface, in which no additional chemical cross-linking was required. In addition, the introduction of K₃[Fe(CN)₆] on the surface of electrode avoided the use of other redox species in the electrolyte solution. Under the optimal experimental conditions, differential pulse voltammetry (DPV) signals corresponding to different α-Fetoprotein (AFP) concentrations were measured. After antigens with different concentrations reacted with antibodies immobilized on the electrode surface, the peak current of DPV gradually decreased with increasing concentrations of AFP. The calibration curve showed a good linear relation in the range from 0.01 to 20 ng·mL^-1 with the linear regression equation of y = -3.23x + 22.42 (R²=0.9943). The detection limit is 0.004 ng·mL^-1 based on a signal-to-noise ratio of 3. The constructed immunosensor is simple, label-free and specific, thus, provides a good diagnostic tool for detection of α-Fetoprotein and other cancer markers.

Graphical Abstract

Keywords

electrochemical immunosensor, K3[Fe(CN)6], aldehyde-functionalized pyridinium, α-Fetoprotein

DOI Link

https://doi.org/10.13208/j.electrochem.170406

Publication Date

2018-04-28

Online Available Date

2017-06-16

Revised Date

2017-06-16

Received Date

2017-04-06

Recommended Citation

Xia HU, You-ming SHEN, Guang-yu SHEN. A Label-free Immunosensor Based on K₃[Fe(CN)₆] and Aldehyde-Functionalized Pyridinium[J]. Journal of Electrochemistry, 2018 , 24(2): 154-159.
DOI: 10.13208/j.electrochem.170406
Available at: https://jelectrochem.xmu.edu.cn/journal/vol24/iss2/7