Desenvolvimento de Genossensores Eletroquímicos para a Detecção Simplificada do DNA do Vírus Zika

Abstract

Biosensors are innovative analytical devices that combine a biological recognition element with a transducer, allowing the sensitive and selective detection of various analytes. Among their applications, the detection of pathogens, such as the Zika virus, which represents a significant challenge to public health, stands out. The search for fast, accurate and accessible methods drives the development of new approaches based on biosensors, especially electrochemical genosensors.

This thesis is structured in three main chapters. The first chapter presents a literature review on advances in the detection of the Zika virus, addressing different methodologies, with a special focus on the use of biosensors for this purpose. The second chapter describes the development of an electrochemical genosensor for the rapid and simplified detection of Zika virus DNA, using safranin as a genomic intercalator on a platform modified with a cysteamine bilayer and carbon quantum dots. This approach aims to improve the sensitivity and specificity of detection, providing an efficient and accessible method. The biosensor demonstrated high sensitivity, detecting 4.2 pg mL-1, selectivity against other arboviruses (chikungunya and dengue), and good stability for at least 45 days.

Finally, the third chapter presents the development of a new electrochemical genosensor based on graphene oxide and safranin for the detection of the Zika virus. This strategy seeks to exploit the unique properties of graphene oxide to improve the electrochemical response. This sensor achieved a detection limit of 8.4 ng mL⁻¹. The genosensor maintained approximately 80% of the response after 60 days, demonstrating good stability.