title: Physico-chemical and thermodynamic aspects of fibroblastic attachment on RGDS-modified chitosan membranes.
abstract: In the present study, the cell attachment/spreading behaviour of L929 mouse fibroblasts on chitosan membranes was evaluated by using physico-chemical properties. For this purpose chitosan membranes were prepared and then photochemically modified with the cell adhesive peptide RGDS (Arg-Gly-Asp-Ser). The physico-chemical properties of unmodified (CHI) and RGDS-modified chitosan (CHI-RGDS) membranes were evaluated by calculating surface free energy (gamma(sv)) and interfacial free energy (gamma(sw)) values using captive bubble contact angle measurements and harmonic mean equation. The cell attachment experiments were performed both in 10% FBS containing and serum-free media with CHI and CHI-RGDS membranes. Eventually, it was not possible to predict a direct relationship between the change in physico-chemical properties and L929 cell attachment behaviour. The experimental results obtained from cell attachment agree with the theoretical prediction for the free energy of adhesion except for the cell attachment on CHI membrane in serum-free medium. Although a negative interfacial free energy of adhesion was calculated for CHI membrane in serum-free medium (DeltaF(adh)=-2.19 ergs/cm(2)), the cell attachment was poor (approximately 70%) compared to CHI-RGDS (approximately 90%) and none of the cells were spread on CHI surface to gain a fibroblastic morphology. Negative energy of adhesion was calculated for CHI and CHI-RGDS in 10% FBS medium, in which approximately 100% of cells were attached on the membranes correlating with the thermodynamic approach. It can be suggested that, adsorption of serum proteins strongly affected the cell attachment meanwhile the presence of biosignal RGDS molecules triggered the cell spreading in serum medium.
authors: Hacettepe University, Chemical Engineering Department, 06800 Beytepe, Ankara, Turkey.
authors: Ayşe Gönen
authors: AG
authors: Karakeçili
authors: Menemşe
authors: M
authors: Gümüşderelioğlu
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D048271:Chitosan / Q000737:chemistry* / Q000378:metabolism*; D016895:Culture Media, Serum-Free; D005347:Fibroblasts / Q000166:cytology*; D008567:Membranes, Artificial; D051379:Mice; D008855:Microscopy, Electron, Scanning; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013816:Thermodynamics
chemical_list: D016895:Culture Media, Serum-Free; D008567:Membranes, Artificial; D009842:Oligopeptides; D048271:Chitosan; C046617:arginyl-glycyl-aspartyl-serine