DEVELOPMENT OF A GENOSENSOR BASED ON SILVER NANOPARTICLE ENCAPSULATED IN Pi-CONJUGATED POLYMER FOR MONITORING OF miRNA IN PATHOGENIC CELLS

• Grant number: 25/06396-0
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: October 01, 2025
• End date: March 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: Marcos Fernando de Souza Teixeira
• Grantee: Miquéias de Lima Portugal
• Supervisor: Felismina Teixeira Coelho Moreira
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil
• Institution abroad: Instituto Superior de Engenharia do Porto (ISEP), Portugal
• Associated to the scholarship: 24/08769-6 - DEVELOPMENT OF A GENOSENSOR BASED ON SILVER NANOPARTICLE ENCAPSULATED IN Pi-CONJUGATED POLYMER FOR MONITORING OF miRNA IN PATHOGENIC CELLS, BP.MS

Abstract

The investigation of the correlation between non-coding RNA (miRNA) and the progression ofinfectious and neoplastic processes has led the scientific effort to minimize the limitations on thedetection of specific miRNA as biomarkers, and, consequently the mechanism studiesfor monitoringpathologies and efficiency of disease treatment. The objective of the present research project willbe the development of a device based on a nanocomposite of silver nanoparticles (AgNPs)encapsulated in Bismarck Brown Y (poly(azo-BBY)) azopolymer for the impedimetric sensing of theglobal level of miRNA-122 in pathogenic cells. The sensorial platform must be constructed byelectropolymerization in a single step in situ in a solution containing the azo-BBY monomer andsilver nitrate in an acidic medium of HNO3 0.10 on the surface of the interdigitalized gold electrode.The gensensor biorecognition will be elaborated by the immobilization of a thiolated DNA probe(ssDNA) on the device surface that it is going to be revested by the blended azopolymer-AgNPs. Inthe following process, the platform will be analyzed by sweep electron microscopy (SEM) and atomicforce microscopy (AFM), to study the nanocomposite morphology. Applying electrochemicalimpedance spectroscopy (EIS) will allow us to investigate the interfacial phenomena of thenanocomposite, enabling a more detailed analysis of the electrochemical characteristics andproperties of the material. The genosensor response mechanism will be based on changes in thesystem impedance values due to the interaction of the miRNA-122 analyte in a phosphate buffersolution at physiological pH with the thiolated ssDNA probe, immobilized on the pi-conjugatedsensitive network of the azopolymer-AgNPs nanomaterial. Subsequently, the final stage of theproject aims to apply the chemiresistor platform in quantitative monitoring of the global level ofmiRNA-122 in HPV pathogenic cells by in vitro assay. At this stage, the research project will bedeveloped in the physiology research group (GPFis) - UNESP, under the supervision of Prof. Dr.Patrícia M. Seraphim, who has extensive experience in studies with biological application. As aninternational collaboration, biological electron transfer reactions, redox signaling mechanisms andtheir interfacial interactions with the sensory platform will be studied in the laboratorycoordinated/directed by Prof. Dr. Felismina Teixeira Coelho Moreira from the Institute of Superior Engineering of Porto, Porto (Portugal)(Portugal). (AU)