A FTIR and SEM study of PS radiation grafted fluoropolymers: influence of the nature of the ionizing radiation on the film structure

International audienc

Elaboration of modelized surfaces with well defined microtopochemistry-localization of adsorbed proteins

Using microphotolithographic techniques, we have been able to devise silica surfaces bearing two types of microdomains with an average width of 40\u3bcm. One of the microdomain types was silanized in order to make them hydrophobic. Fourier transform-infrared (FTIR) and Auger electron spectroscopies (AES) were used to check the presence of the expected chemical groups on the modified silica surface. Silica and silanized surface morphology was studied using Scanning Force Microscopy (SFM). Wetting properties were investigated. Protein adsorption studies were performed using diluted human decalcified plasma. Attention was focused on the topographic distribution of the adsorbed molecules in order to establish a correlation between the protein behaviour and the specific chemistry of each type of microdomain. Copyright (C) 2000 Elsevier Science B.V

Synthesis of biomaterials by swift heavy ion grafting: Preliminary results of haemocompatibility

International audienc

Impact of RGD Nanopatterns Grafted onto Titanium on Osteoblastic Cell Adhesion

This work reports on the synthesis of titanium bone implants functionalized with nanoparticles (NPs) containing Arg-Gly-Asp-Cys peptide (RGDC) and shows the adhesion behavior of cells seeded on these materials. RGDC peptides were first: conjugated to a norbornenyl-poly(ethylene oxide) macromonomer (Nb-PEO). Then, functional NPs with a size of similar to 300 nm and constituted of polynorbornene core surrounded by poly(ethylene oxide) shell were prepared by ring-opening metathesis polymerization in dispersed medium. The grafting density of these NPs on the titanium surface is up to 2 NPs.mu m(-2) (80 pmol of RGDC per cm(-2) of NP surface). Cell adhesion was evaluated using preosteoblast cells (MC3T3-E1). Results of cells cultured for 24 h showed that materials grafted with NPs functionalized with RGDC peptides enhance specific cell adhesion and can create filopodia-like among NP sites by stressing the cells

Peptide immobilization on polyethylene terephthalate surfaces to study specific endothelial cell adhesion, spreading and migration.

To control specific endothelial cell (EC) functions, cell adhesive RGDS, EC specific REDV and YIGSR peptides, and angiogenic SVVYGLR sequences were covalently immobilized onto polyethylene terephthalate (PET) surfaces for the purpose of cell culture. X-ray photoelectron spectroscopy, atomic force microscopy, fluorescence microscopy and contact angle measurement were employed for characterization of surface modifications. The peptide density on PET surfaces was evaluated by fluorescence microscopy. The surfaces immobilized with peptides were exposed to human umbilical vein endothelial cells to study their specific effects onto EC functions. The results showed that the surface functionalized by these peptides enhanced the EC adhesion, spreading and migration as compared with native PET surfaces. Specifically, the RGDS peptides induced more cell adhesion than other peptides. The YIGSR and SVVYGLR sequences induced more cell spreading and cell migration, represented by intense focal adhesion at the leading edges of cell spreading and migration. The bi-functionalization of RGDS and SVVYGLR peptides (MIX) combined the advantages of both peptides and induced significant EC adhesion, spreading and migration. Our study indicates that the surface functionalization by peptides specific for ECs, especially the combination of RGDS with SVVYGLR or YIGSR peptides, has potential applications in promoting endothelialization of vascular prostheses and for construction of vascularized tissues in tissue engineering