| AVS 54th International Symposium | |
| Biomaterial Interfaces | Thursday Sessions |
| Session BI-ThP |
| Session: | Biomaterial Interfaces Poster Session |
| Presenter: | G. Ceccone, EC-JRC-IHCP, Italy |
| Authors: | G. Ceccone, EC-JRC-IHCP, Italy D. Gilliland, EC-JRC-IHCP, Italy I. Liakos, EC-JRC-IHCP, Italy F. Rossi, EC-JRC-IHCP, Italy M. Morra, Nobil-Bio-Ricerche, Italy C. Cassinelli, Nobil-Bio-Ricerche, Italy G. Cascardo, Nobil-Bio-Ricerche, Italy C. Della Volpe, University of Trento, Italy R. Verhoef, University of Wageningen, The Netherlands H. Schols, University of Wageningen, The Netherlands |
| Correspondent: | Click to Email |
The exploitation of the bio-active properties of polysaccharides covalently linked to materials surfaces is a rapidly growing area of biomaterials surface science. Recent findings on bioactivity of plant carbohydrate polymers are spurring an activity of biomolecular scouting and suggest that pectic polysaccharides are promising flexible molecules for novel bioactive surfaces. In this work we have investigated the properties of surface linked pectic rhamnogalacturonans(RG-I) fractions(MHRs) obtained by commercial enzyme preparations of homogenized vegetable tissue. MHRs were covalently linked to different substrates, namely polystyrene(PS), Titanium(Ti) and polycarbonates(PC) surfaces aminated by glow discharge plasma and analysed by XPS, ToF-SIMS, AFM, and contact angle measurement. Cell adhesion experiments using L-929 fibroblasts and Aortic Smooth Muscle cells(SMC) were performed to evaluate the effect of the MHRs nature on cell adhesion. Moreover, cells growth and specific alkaline phosphatase (ALP) activity of osteoblast-like SaOS2 cells were also measured. Surface analyses of different samples indicate that coupling of MHRs polysaccharides was successful for all substrates. XPS analysis of plasma amminated PS shows significant amount of N (13at%) related to the presence of amino groups. After MHRs coupling, strong increase of O/C ratio is detected, whilst nitrogen signal is still present indicating that the thickness of MHR layer is below the XPS sampling depth(<10nm).ToF-SIMS analysis supports the XPS data: amminated surfaces present CxHyN peaks expected in allylamine-like films, whilst large fragments peaks (m/z>250amu) are observed both on parent and on surface-coupled polysaccharides.AFM force-separation curves show that immobilization of MHRs significantly affects the interfacial forces with the absence of any attractive interaction until repulsive contact is reached. Results of cells experiments reveal that the structure of the immobilized MHRs (long vs short hair) has great influence on adhesion, morphology and cells enzymatic activity. In particular the long-haired MHRs are found less adhesive. Interestingly, specific ALP activity of the modified surfaces is upregulated respect to that of the control, suggesting that MHRs coated surfaces present interfacial properties suitable for osteoblast differentiation.
*This work is carried out within the EU STREP Project # 517036 (PECTICOAT).