Functionalization of polymer fibers with heparan sulfate as a representative of the extracellular matrixPart of:
The application of polymer fibers consisting of poly-ε-caprolactone (PCL) and polyglycolide (PGA) has already been widely studied in the field of biomedical sciences. Both polymers have been used for example as basic material for drug delivery systems or 3D-scaffolds in tissue engineering. They allow an efficient modification of their physical, chemical and mechanical properties by copolymerization or blending with many other polymers as well as by surface functionalization. Moreover they have shown a good biocompatibility and are biodegradable. The aim of this work is to modify the surface of fibers made from PCL/PGA copolymers in order to test their applicability as components in scaffolds for tissue regeneration. For this purpose, the biodegradable fibers were coated with heparan sulfate as a representative of extracellular matrix components; heparan sulfate is also an anticoagulant and could enhance wound healing after implantation. It is well-known in clinical applications and is, for example, used in the eyedrops Cacicol® to regenerate and heal the cornea.
In this work the polymer fibers are functionalized with aminogroups via aminolysis using ethylenediamine. Afterwards heparan sulfate is linked covalently to the functionalized fibers using coupling and stabilizing agents. Toluidine blue was used in a colorimetric assay to validate the presence of heparan sulfate on the fibers. Furthermore, cell culture investigations with fibroblasts showed a good cytocompatibility.
This work was supported by the Cluster of Excellence Hearing4all.
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