Exploring the architecture of an analytical device for the determination of Enterococcus faecalis

• Grant number: 24/18902-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2024
• End date: November 30, 2025
• Field of knowledge: Interdisciplinary Subjects
• Principal Investigator: Augusto Etchegaray Júnior
• Grantee: Lucas Vinicius Vicentin da Silva
• Host Institution: Pró-Reitoria de Pesquisa, Pós-Graduação e Extensão. Pontifícia Universidade Católica de Campinas (PUC-CAMP). Campinas , SP, Brazil

Abstract

Developing methods to detect infectious diseases is crucial for a healthcare professional. Among the current methods is the selective identification of microorganisms that cause infection, such as bacteria, fungi, viruses, and parasites. In this project, we have focused on Enterococcus faecalis, a bacterium that causes dental pulp infection, endocarditis and urinary tract infections, especially in hospitalized patients. In dentistry, E. faecalis can delay and even interfere with endodontic treatment. Although detection methods for E. faecalis already exist, such as microbiological assays and DNA amplification, there is a lack of rapid methods based on biosensors that can be performed at the point of care, a dental care office or an outpatient clinic. Several architectures can be explored when preparing a biosensor, such as antibody and aptamer immobilization as recognition elements. This project aims to contribute by evaluating two specific arrangements for a device to detect E. faecalis based on the immobilization of polyclonal antibodies and an aptamer, also specific for E. faecalis on core-shell nanoparticles of zinc oxide coated with gold. This material will be deposited on disposable carbon-printed microelectrodes, and the interaction with samples containing diluted suspensions of E. faecalis will be evaluated through electrochemical experiments, using differential pulse voltammetry. It is expected that the antibodies and the aptamer will be successfully immobilized, that they will form a stable nanocomposite and that this will generate reproducible results. Finally, that E. faecalis can be determined with specificity and sensitivity as in other processes based on biosensors.