Heterogeneous Electrochemical Immunoassay of Hippuric Acid on the Electrodeposited Organic Films

Sensors

Young-Bong Choi²  Nam-Hyuk Kim²  Seung-Hoi Kim²  Gun-Sik Tae¹ 

[1] Department of biology, College of Natural Science, Dankook University, Anseo-Dong, Cheonan 330-714, Korea; E-Mail:;Department of chemistry, College of Natural Science, Dankook University, Anseo-Dong, Cheonan 330-714, Korea; E-Mails:

关键词: hippuric acid;    toluene;    electrochemical immunosensor;   

DOI  :  10.3390/s141018886

来源: mdpi

【 摘 要 】

By directly coordinating hippuric acid (HA) to the ferrate (Fe) as an electron transfer mediator, we synthesized a Fe-HA complex, which shows a good electrochemical signal and thus enables the electrochemical immunoanalysis for HA. We electrodeposited organic films containing imidazole groups on the electrode surface and then bonded Ni ion (positive charge) to induce immobilization of Fe-HA (negative charge) through the electrostatic interaction. The heterogeneous competitive immunoassay system relies on the interaction between immobilized Fe-HA antigen conjugate and free HA antigen to its antibody (anti-HA). The electric signal becomes weaker due to the hindered electron transfer reaction when a large-sized HA antibody is bound onto the Fe-HA. However, in the presence of HA, the electric signal increases because free HA competitively reacts with the HA antibody prior to actual reaction and thus prevents the HA antibody from interacting with Fe-HA at the electrode surface. This competition reaction enabled an electrochemical quantitative analysis of HA concentration with a detection limit of 0.5 μg mL⁻¹, and thus allowed us to develop a simple and rapid electrochemical immunosensor.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.