Construction and Application of a Novel Impedance Sensor for Siderophore

摘要

Siderophore is a potential biomarker for pathogen diagnosis. In this study, a siderophore impedance sensor was constructed based on the formation of a siderophore-hemin complex prepared by modification of hemin on an interdigitated array microelectrode. Siderophore reacted with hemin and formed a complex on the electrode surface. As the conductivity of hemin was higher than that of siderophore, the formation of the complex led to decrease of conductivity on electrode surface which was measured by electrochemical impedance spectroscopy. The impedance change of constructed sensor was linear with the concentration of siderophore between 1nM and 100 mu M, with a limit of detection of 0.86nM. The detection time was less than 15min. When the sensor was used to analyze medium, the recovery was between 86.7% and 102.8%. Compared with conventional methods for siderophore, this approach is faster, more sensitive, and has potential application for the determination of pathogens.