Banca de DEFESA: PAULO CÉSAR FRANÇA DA CÂMARA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : PAULO CÉSAR FRANÇA DA CÂMARA
DATE: 02/02/2021
TIME: 13:00
LOCAL: Remotamente pelo Google Meet
TITLE:

Obtaining biomaterials using tannin derivatives and glycosaminoglycans for applications in tissue engineering and regenerative medicine

KEY WORDS:

Polyelectrolyte multilayers, Glycosaminoglycans, Tannins, Biomaterials, Stem cells.

PAGES: 100
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Polímeros e Colóides
SUMMARY:

Develop stable polysaccharide structures with biochemical and biomechanical properties used by extracellular matrix (ECM) is one of the goals of tissue engineering and regenerative medicine. Improve the biocompatibility of conventional materials through surface modification has been shown to be an effective way to enhance their biological response. In addition, biomaterials used in medical devices need to be compatible with various biological environments, not activating the patient's immune system, leading to rejection and failure of these materials. We report a new class of surface coatings for the purpose of enhancing biocompatibility and cellular response using multilayer self-assembled polyelectrolytes (PEMs) with a derivative of cationic tannins and glycosaminoglycans (chondroitin sulfate or heparin) because they exhibit similar chemical structures to found in ECM. The construction of polyelectrolyte multilayers was monitored by Fourier Transform Surface Plasmon Resonance (FT-SPR). The surface properties were assessed by X-ray Excited Photoelectron Spectroscopy (XPS), Atomic Force Spectroscopy (AFM) and contact angle measurements. The response of human adipose-derived stem cells (ADSCs) was evaluated in vitro through cytocompatibility assays, adhesion and proliferation of the cells using fluorescence microscopy. For the hemocompatibility assays, the adsorption of serum protein, adhesion and platelet activation, as well as whole blood coagulation assays was monitored by XPS, scanning electron microscopy (SEM) and visible ultraviolet (UV-vis) spectroscopy. The interactions of ADSCs with these new biomaterial surfaces demonstrate that these surface coatings exhibit good cytocompatibility and that they promote cell attachment and proliferation. Blood tests point to the high potential of developing hemocompatible materials through tannin derivatives. Particularities in the chemical structure of tanfloc were signaled as crucial in the control of blood protein adsorption, such as fibrinogen, creating an antiplatelet effect on the surface of the materials. The association between biomaterial components and cells and key bioactive molecules in biological processes important in the reconstruction of large tissue losses highlights the great potential of materials. These characteristics are very desirable for biocompatible coatings for applications such as tissue engineering scaffolds and medical devices.

 

BANKING MEMBERS:
Externo ao Programa - 2220417 - CARLOS AUGUSTO GALVAO BARBOZA
Externa à Instituição - DENISE FREITAS SIQUEIRA PETRI - USP
Interno - 1198847 - JOSE LUIS CARDOZO FONSECA
Externa ao Programa - 2212519 - JULIANA DE SOUZA NUNES
Externo à Instituição - PAULO NORONHA LISBOA FILHO - UNESP
Presidente - 1149440 - ROSANGELA DE CARVALHO BALABAN