Desenvolvimento de um genossensor e validação de testes moleculares para identificação e diferenciação de espécies patogênicas de Candida spp.

Abstract

The diagnosis of invasive fungal infections caused by species of the Candida genus remains a significant challenge in clinical practice, especially in hospital settings. It is estimated that there are approximately 6.5 million invasive infections, with 3.8 million people dying from invasive fungal diseases (IFDs) each year. Candidemias represent one of the most common causesof fungal infections in humans, with Candida albicans being the most prevalent species, responsible for 40% of the global rate of systemic infections. Although modern methods such MALDI-TOF mass spectrometry, VITEK na Polymerase Chain Reaction (PCR) have increased diagnostic accuracy and sensitivity, a important gap remains

regarding the efficiency, cost and availability of faster, more accessible, and real- time approaches applicable in clinical practice. Early detection is essential for the

implementation of effective antifungal therapies, contributing to a reduction in morbidity and length of hospital stay. The objective of this work is to developa genossensor and validate molecular tests to identify and differentiation of Candida albicans, Candida tropicalis, and Candida parapsilosis, with high sensitivity and specificity, rapid results, and low cost. This work proposed na electrochemical biosensor using a glassy carbono modified with iron oxide nanoparticles, carbono nanotubes, and DNA probes (ECV/NTCPM/Fe2O3/DNA)

for detection and differentiaton of the Candida species studied here. The FeNP- CNT-DNA electrode showed significant current results in the presence of C.

albicans, confirming the viability of the biosensor for electrochemical deteccion of the patogen and pathogen and the continued development of the genosensor. Furthermore, it was that the conventional PCR technique stood out in comparasion to the MALDI-TOF and VITEK methods due to its intermediate cost and excellent sensitivity and specifity for detecting Candida spp., especially because it was the only technique that managed to identify the largest number of co-infections in the samples examined, an essential fator for more assertive terapeutic mangement in the search for a cure for patients.