Polyaniline Based Electrochemical Sensor for the Detection of Dengue Virus Infection

Dengue burden is increasing day-by-day globally. A rapid, sensitive, cost-effective early diagnosis kit is the need of the hour. In this study, a label-free electrochemical immunosensor was proposed for dengue virus detection. A modified Polyaniline (PANI) coated Glassy Carbon (GC) electrode, immobilized with DENV NS1 antibody was used to detect the circulating DENV NS1 antigen in both spiked and infected sample.

Cloning, purification and expression of DENV NS1 protein in Escherichia coli (E. coli) was performed and sensor design, PANI modification on GC electrode surface by electrochemical polymerization and immobilization of NS1 antibody on the modified electrode surface was done and finally the analytical performance of the electrochemical immunosensor was done using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS).

CV and EIS were used to study and quantitate the circulating DENV antigen. The calibration curve showed wide linearity, good sensitivity (Slope=13.8% IpR/ml.ng-1) and distribution of data with a correlation coefficient (R) of 0.997. A lower Limit of Detection (LOD) was found to be 0.33 ng.ml-1 which encourages the applicability of the sensor.

Thus, a PANI based new electrochemical immunosensor has been developed which has the potential to be further modified for the development of cost effective, point of care dengue diagnostic kit.