Nanocoatings containing sulfated polysaccharides prepared by Layer-by-Layer as models to study cell-materials interactions

The understanding of both cell-extracellular matrix (ECM) and cell-materials interactions is crucial for the success of implantable biomaterials including tissue engineering devices. ECM is rich in sulfated and aminated glycosaminoglycans and proteoglycans. The development of synthetic models containing those chemical groups is thus of major interest. Thin coatings of polysaccharides with controlled sulphur and nitrogen content were developed by Layer-by-Layer assembly. In particular, the multilayers were prepared by assembling chitosan with κ-, ι- and λ-carrageenan (increasing sulphur content). The nanostructured multilayers where characterized by quartz crystal microbalance with dissipation (QCM-D), atomic force microscopy (AFM), scanning electron microscopy (SEM), water contact angle, x-ray photoelectron spectroscopy (XPS) and used as models to study the effect of the sulfonic groups over the behaviour of osteoblast-like cells. The biomimetic coatings increased ALP activity and proliferation comparing with unmodified polycaprolactone surfaces. Biomineralization on ι-carrageenan coatings was significantly higher than with other coatings, suggesting that the sulfonic groups may interact positively with molecules involved in the osteoblastic activity as it occurs in the natural ECM. The developed nanocoatings can constitute an interesting model to understand the biological influence of the sulfonic and amine groups existing on the surface of biomaterials.