Nanoscale Organization of Peptide Hydrogel Matrices: Topography, Cell Adhesion, and Nanomechanical Properties

• Grant number: 25/11824-1
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: August 01, 2025
• End date: July 31, 2028
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Emerson Rodrigo da Silva
• Grantee: Giovanna Jardim Vieira Pereira dos Santos
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated research grant: 22/03056-6 - Ultrastructural characterization of bioactive nanoscaffolds, AP.PNGP.PI

Abstract

Self-supporting matrices formed from the connection and entanglement of peptide fibers represent a class of materials with great potential in frontier areas such as nanomedicine and tissue engineering. The proper use of these systems requires a detailed knowledge of their ultrafine structure, on a nanoscopic scale, since it is on this size scale that most of the interactions occur, defining the macroscopic properties of these systems. Atomic force microscopy (AFM) is one of the most interesting tools for directly visualizing these structures and measuring the forces involved. It is a method that makes it possible to obtain three-dimensional maps of these interfaces, as well as to establish roughness parameters, force-distance curves, hardness and adhesion forces with great precision. This thesis will be based on the study of the nanoscopic structure of hydrogel matrices formulated from cell-penetrating peptides (CPPs). The peptide sequences analyzed here will consist of a combination of structuring segments already known in the literature covalently linked to bioactive segments with CPP characteristics. The origin of these CPPs will be based on viral proteomes, particularly of the new coronavirus. Once formulated, these matrices will be used to functionalize surfaces for subsequent analysis of adhesion with cells in culture medium. These substrates will be analyzed in great detail in terms of the organization of the fibrillar network at the interface and the interaction forces they promote. In the end, we expect to establish correlations between the structure of the materials and the cell adhesion capacities they demonstrate. (AU)