Effects induced by synthetic food dyes in 2D and 3D bioinspired membrane systems

• Grant number: 25/00337-2
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: August 01, 2025
• End date: July 31, 2030
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Carlos José Leopoldo Constantino
• Grantee: Carlos Junior Amorim Lessa
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

This Direct Doctorate (DD) project proposes the development of bioinspired 2D and 3D systems of intestinal barrier cell membranes to study the impact of synthetic food dyes Allura Red AC (AR - anionic), Brilliant Blue (BB - zwitterionic), and Rhodamine B (RdB - cationic), focusing on the inflammation mechanisms involved. The research aims to deepen the study developed by the candidate during their undergraduate research (FAPESP 2023/00291-7), refining bioinspired systems of the intestinal barrier and developing studies using in vitro models. The fundamental bioinspired system addressed in this project consists of lipid bilayers structured as giant unilamellar vesicles (GUVs - 3D system) formed from ternary mixtures of POPC/POPE/SM in a 3/1/1 mol% ratio, ensuring similarity in terms of chemical composition, size, and fluidity to intestinal tract cells. Additionally, GUVs with a quaternary mixture of POPC/POPE/SM/DPPS in a 2/1/1/1 mol% ratio will be investigated, as serine lipids, represented by DPPS, contribute to the regulation of the intestinal inflammatory environment. Dye exposure will be carried out via microinjection, and their effects on GUV morphology will be monitored using confocal fluorescence microscopy. The lipid-dye interaction at the molecular level will be determined via vibrational spectroscopy, both for GUVs using micro-Raman scattering and for lipid monolayers (Langmuir films - 2D system) through polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS). Additionally, artificial parallel membrane permeability assays (PAMPA - 2D system) and phospholipid vesicle-based permeation assays (PVPA - 2D system) will be developed to evaluate dye permeability in bioinspired membranes of intestinal barrier cells. Finally, the project will include 2D cell cultures for toxicity and immunoassay tests, to be conducted during a research internship (BEPE) at the University of Southern Denmark, Odense, Denmark, under the supervision of Professor Jonathan Brewer, who leads one of Europe's reference microscopy centers. This DD proposal is linked to the Thematic Project FAPESP 2018/22214-6, in which the advisor is the principal investigator, and to the PQ-1B grant from CNPq. It will also be co-supervised by Dr. Gilia Cristine Marques Ruiz, a FAPESP postdoctoral researcher specializing in membrane mimetic systems. (AU)