Dhahri M.,University of Monastir |
Abed A.,French Institute of Health and Medical Research |
Mansour M.B.,University of Monastir |
Gueguen V.,French Institute of Health and Medical Research |
And 5 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2011
The aim of the present study was to achieve the immobilization of dermatan sulfate (DS) on polyethylene terephthalate (PET) surfaces and to evaluate its biocompatibility. DS obtained from the skin of Scyliorhinus canicula shark was immobilized via carbodiimide on knitted PET fabrics, modified with carboxyl groups. PET-DS characterization was performed by SEM, ATR-FTIR and contact angle measurements. Biocompatibility was evaluated by investigating plasma protein adsorption and endothelial cell proliferation, as well as by subcutaneous implantations in rats. The results indicated that DS immobilization on PET was achieved at ∼8 μg/cm2. ATR-FTIR evidenced the presence of sulfate groups on the PET surface. In turn, contact angle measurements indicated an increase in the surface wettability. DS immobilization increased albumin adsorption on the PET surface, whereas it decreased that of fibrinogen. In vitro cell culture revealed that endothelial cell proliferation was also enhanced on PET-DS. Histological results after 15 days of subcutaneous implantation showed a better integration of PET-DS samples in comparison to those of nonmodified PET. In summary, DS was successfully grafted onto the surface of PET, providing it new physicochemical characteristics and biological properties for PET, thus enhancing its biointegration. © 2011 Wiley Periodicals, Inc.
El Oudiani A.,Unite de Recherches Textiles |
El Oudiani A.,University of Monastir |
Chaabouni Y.,Unite de Recherches Textiles |
Chaabouni Y.,University of Monastir |
And 4 more authors.
Journal of the Textile Institute | Year: 2012
This study investigates the change in crystalline structure of Agave americana L. fibers during alkali process at different NaOH concentrations. X-ray diffraction spectroscopy was used to determine the crystallinity, the crystal size, and the unit cell dimensions of the treated Agave samples. The X-ray diffractograms of both untreated (0% NaOH) and alkali-treated samples show a pattern quite similar to the four peaks characteristic of native cellulose (cellulose I). The intensity of the (0 0 2) crystallographic plane increased significantly by alkali treatment of Agave fiber. When treated with 2% wt/v NaOH, the polymorphic transformation of cellulose I to cellulose II occurs as indicated by the appearance of the diffraction at 2θ = 20.5° resulting from the (101 -) lattice plane of cellulose II. The unit cell parameters of Agave americana L. fibers vary with NaOH concentration which results from the formation of different alkali celluloses during the mercerization process. As far as mechanical properties are concerned, treatments with low alkali concentrations produce fibers that are stronger than the untreated fibers, whereas treatments with high concentrations (>2% wt/v) result in weaker fibers. © 2012 Copyright The Textile Institute.