O ciclo semanal de seminários do CCMC recomeçou nesta manhã, com a apresentação do trabalho que vem sendo realizado pelo Dr. Rodney Marcelo do Nascimento, pós-doc do Grupo de Pesquisa, o qual tem a supervisão do Professor Antonio Carlos Hernandes.
A pesquisa de Rodney consta no resumo abaixo, contendo os temas expostos no seminário apresentado nesta manhã.
WETTING PROPERTIES OF NATURAL RUBBER-CALCIUM PHOSPHATE SURFACES
To act as a mechanical barrier and induce bioactivity, the understanding of the surfaces properties of membranes is a required to the biomaterial-bone interface remains stable until complete tissue regeneration. In this work, natural rubber (NR) obtained from Hevea brasiliensis tree composed of poly-isoprene rubber-matrix with Hevein proteins (Hev. b1 and Hev. b3) particles was processed to obtain thin film and sustainable membranes. Calcium phosphate (CaP) micro grains with multi-crystalline phases, including Ca5P8 (47.8 wt. %), CaCO3(36.3 wt.%), Ca(PO4)3OH (9.5 wt.%) and Ca (6.3 wt.%), obtained by sol-gel, were incorporated in the polymeric matrix to produce a functionalized surface. The structural and vibrational characterization by confocal spectrum-microscopies probing shows the CaP particles trapped by proteins. As first finding of the surface effects: the morphology was changed. Sequentially, different wettability aspects were studied in detail to establish a relation between roughness, free energy and the contact line dynamics. The wettability effects were observed under different dynamic mode by monitoring the evolution of contact radius and the contact angle as function of time R(t), q(t). Induced pinning effects at contact line were found by two experimental ways and attributed to decreasing heterogeneity wetting. A modeling using micro-patterned surfaces was introduced to investigate the phases fractions f1, f2 and similar behavior of R(t) and q(t) were observed to NR and NR-CaP. The induced pinning by NR-CaP trapped on surfaces is discussed in terms of soft matter, taking account the possible consequences in the dynamic of bio fluids on surfaces as a first stage of tissue regeneration.
*Os seminários do CCMC são abertos a todos os seus membros e também a pesquisadores externos ao grupo, e ocorrem, semanalmente às quintas feiras, na Sala 14, Prédio Administrativo do IFSC/USP, das 10h às 11h.