The COVID-19 pandemic showed that more accessible and faster diagnostic platforms are crucial for the effective control of viral diseases, as they allow the rapid isolation of infected people, the choice of the most appropriate treatment and the knowledge of the geographical distribution of the disease to manage resources for the public health system in the most affected regions. In this project, capacitive electrochemical sensors will be developed to detect biomarkers of the Dengue virus and a virus responsible for a sexually transmitted disease (HPV-16 or HTLV-1), with the aim of overcoming the limitations of conventional diagnostic techniques and allowing the wide performance of tests even in regions without laboratory infrastructure. The detection proposal based on reagentless methods is advantageous because the sample preparation is simple and can be used in the initial phase of the disease, overcoming deficiencies associated to conventional molecular tests (RT-PCR). Impedimetric electrochemical biosensors have been widely explored for the diagnosis of diseases due to their high sensitivity and for providing fast results. However, some approaches to perform the analyzes represent a challenge for point-of-care application. Therefore, an electrochemical strategy free of redox probes in solution, without using redox probe reagent, based on the capacitance derived from the impedance will be employed in our viral detection platform. The peptides will be conjugated to ferrocene molecules, used as redox radicals, and self-assembled on printed circuit board (PCB) electrodes. Bioreceptor molecules will then be added to the monolayer and the detection platform will be tested in the field with clinical samples. All electronic circuits necessary for the acquisition of the sensor signal will be combined in a potentiostat of the size of a pen-drive to be connected to a smartphone where specific software will process the data and provide the result on the screen. We believe that our platform can be effective for the point-of-care diagnosis of viral infections, representing a fundamental tool for massive testing and control of epidemics.
News published in Agência FAPESP Newsletter about the scholarship: