Final Report Summary - POLY-INTER-FACES (Micro- and Nanostructured Polysaccharide Interfaces)
To reach the project`s objectives silylated polysaccharide derivatives were produced and characterized in detail with respect to their chemical composition, solubility and processability. These silylation reactions allowed the processing and blending of polysaccharide derivatives which are otherwise not miscible. Besides others it included the silylation of chitosan, hydroxyethyl cellulose and cellulose that could then be formed into blend films or electrospun into micro- or nano-fibers and particles. Cleavage of silyl protecting groups after material processing led to the formation of polysaccharide blends with characteristic surface properties and tailored interaction with biomolecules.
It was for instance found that films containing uncharged highly hydrated cellulose, dispersed in a matrix of hydrophobic cellulose derivatives (e.g. cellulose acetate, ethyl cellulose), exhibits very low unspecific adsorption of serum albumin under physiological conditions. By decreasing the amount of cellulose in this matrix, adsorption of albumin could be strongly influenced. In contrast it was found that the plasma protein fibrinogen, which plays a key role in blood coagulation, strongly binds to cellulose acetate surfaces but not to other micro-structured hydrophobic/hydrophilic polysaccharide blends, a fact that is of significant importance for the biomedical application of the investigated materials. Protein binding to surfaces could also be influenced by deposition of cationic charges on the aforementioned materials.
The project`s final aim was the exploitation and utilization of the tailored materials` properties. These applications included the use as a biosensor platform for the fluorescence based detection of DNA, owing to the low unspecific adhesion of this biomolecule and the specific immobilization of probes by polymer adsorption. Alternative applications targeted the use of the materials as substrates for the growth of living cells in tissue engineering, an emerging topic in medicine. The project`s results also included the development of coatings for functional wound dressings which contain anti-inflammatory substances that can be released in a controlled manner to possibly heal chronic wounds. As a results the project`s impact strongly contributed to the sustainable use of natural resources, the understanding of basic phenomena at the interface and the application of the materials in the biomedical field. The project idea and results address a large variety of target groups namely the bio-based industry as a producer of raw-materials and products, the bio-medical sector and households as consumers of point-of care diagnostic devices, and medical wound dressing materials. It is expected that some of the developed materials and applications can be developed further, brought to the market and lead to innovation, growth, job opportunities and advances in health care.