Advanced Electrochemical Genosensor for Zika Virus Detection in Biological Samples Based on Cysteamine-Graphene Quantum Dots Bilayer

Abstract

This paper describes a novel electrochemical genosensor designed for rapid and simplified detection of Zika virus DNA, using the biological dye safranin as a biomolecular intercalator. The genosensor uses a gold-printed circuit board as electrode, modified with a bilayer formed by cysteamine and graphene quantum dots to immobilize oligonucleotide probes specifically designed for the detection of the Zika virus. The genosensor construction was monitored by scanning electron microscopy (SEM), dynamic force microscope (DFM), and Fourier transform infrared (FTIR). Electrochemical detection was carried out based on differential pulse voltammetry, monitoring the peak current of the DNA intercalator (safranin). The genosensor demonstrated high sensitivity, detecting 1.2 pg mL−1, selectivity against other arboviruses (chikungunya and dengue) and good stability for at least 45 days. These parameters indicate potential for use of this genosensor in medical diagnostic testing for Zika virus, aiming at early screening of patients, especially in epidemic situations.