Detection and discrimination of alpha-fetoprotein with a label-free electrochemical impedance spectroscopy biosensor array based on lectin functionalized carbon nanotubes

► An EIS biosensor for the determination of AFP was developed. ► Lectin was employed as the molecular recognition element. ► The detection limit for AFP was 0.1 ng/L. ► A biosensor array was used to evaluate the glycan expression of AFP N-glycan. ► A biosensor array was used to discriminate AFP between healthy and cancer serums.