A simple electrochemical genosensor based on polythiophene acetic acid film for detection of Schistosoma mansoni

Schistosoma mansoni infection and other neglected diseases pose significant challenges in diagnosis and treatment, particularly in resource-constrained regions. Despite being useful, traditional techniques lack sensitivity, offering frequent false-positive results, highlighting the emergence of innovative tools such as genosensors as a promising solution to this dilemma. In this work, we developed a simple electrochemical biosensor platform based on electropolymerized films of polythiophene acetic acid (PTAA) and a specific DNA probe for the detection of S. mansoni. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and atomic force microscopy (AFM) were used to assess the assembly process of the genosensor, as well as to evaluate biodetection assays. The developed biosensor was found to be effective in detecting the target analyte in pure and complex samples such as cerebrospinal fluid, urine, and plasma from infected patients at different concentrations. CV and EIS were extremely useful in the evaluation of the detection process based on the electron kinetics and charge transfer resistance (R_CT) in the interface of the biosensor, where the hybridization with the target single-stranded S. mansoni DNA resulted in the variation of these parameters. The genosensor exhibited high sensitivity and selectivity, with a limit of detection of 0.451 pg.μL⁻¹. As genosensors continue to evolve, they promise to revolutionize the field of neglected disease management, providing hope for improved healthcare outcomes worldwide.