A novel approach to classify serum glycoproteins from patients infected by dengue using electrochemical impedance spectroscopy analysis

Electrochemical biosensor for serum glycoproteins (SG) from patients infected by dengue fever (DF) based on gold nanoparticles (AuNp) and polyvinyl butyral (PVB) adsorbed on gold electrodes has been investigated. Electrochemical impedance spectroscopy (EIS), in the frequency range from 100 mHz to 100 kHz, was performed on these electrodes, in phosphate buffer (PBS) solution containing 10 mM K3[Fe(CN)6]/K4[Fe(CN)6] (1:1) as a redox probe. The electrodes modified with AuNp–Con A–PVB–BSA–SG showed larger electron transfer resistances than those modified with AuNp–Con A–PVB–BSA. The impedance spectra showed an increase in the charge transfer resistance when Con A interacted with SG. Moreover, the charge transfer resistance obtained with DF was larger than that obtained with negative serum. The resulting biosensor is capable to recognize SG from patients infected by DF.