Detection of dengue virus serotypes on the surface of gold electrode based on Cratylia mollis lectin affinity

We describe the development of a biosystem to analyze the interactions between CramoLL lectin and fetuin to be applied in the detection of glycoprotein from the serum of patients contaminated with dengue serotypes 1, 2 and 3 (DS1, DS2 and DS3, respectively). The different modified gold electrodes were characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques. SEM analyses of PVB-Fe(3)O(4)Nps-CramoLL-BSA-DS1, PVB-Fe(3)O(4)Nps-CramoLL-BSA-DS2 and PVB-Fe(3)O(4)Nps-CramoLL-BSA-DS3 samples have revealed the existence in all cases of a heterogeneous distribution of PVB spherules. EIS and CV measurements have shown that redox probe reactions on the modified gold electrodes were partially blocked, owing to the adsorption of PVB-Fe(3)O(4)Nps-CramoLL, and confirm the existence of a positive response of the immobilized CramoLL to the presence of fetuin and glycoproteins of dengue serum. The biosensor exhibited a wide linear response to different concentrations of sera of dengue serotypes 1,2 and 3 and also a higher response to glycoproteins present in dengue serotype 2. These studies might be useful as a platform for the design of new reusable and sensitive biosensing devices that could be of use in dengue diagnosis. (C) 2011 Elsevier B.V. All rights reserved.