Degradable hybrid polymers for tissue engineeringPart of:
There are high demands on scaffold materials applied in the field of tissue engineering. For example, the medical field of bone regeneration requests a particular combination of properties like degradability, resorbability of degradation products by the human body, biocompatibility and a suitable Young’s modulus. Furthermore, the design of the produced scaffolds is very important as the cultivated cells need to invade and grow and thus give new bone regeneration. Individual shaping for a patient as well as establishing structures for nutrient and oxygen supply within the scaffold are basic requirements.
In order to conform to all these aspects a degradable and bioresorbable organic-inorganic hybrid polymer was developed. Due to the integration of hydrolytic and/or enzymatic cleavable groups in the organic part of the hybrid material, degradation is enabled. The organic curing of the inorganic pre-crosslinked resin is achieved by a Thiol-ene reaction with a crosslinking agent containing further cleavable groups. The radical Thiol-ene curing reaction can be initiated photochemically and therefore provides the opportunity to process the material in a 3D printer (DLP principle) and allows an individual multiform shaping. Since the material is assembled in a modular way modifications can be introduced simply. Hence the Young’s modulus already covers a range of 8 – 2100 MPa and can be adapted to a big variety of human tissue. The degradation rate depends on the hydrophilic properties of the underlying chemical structure. Therefore, various hybrid polymer systems show a mass loss within 16 weeks between 6 – 100 wt.% in a carbonate buffer solution. It was possible to observe the expected degradation products by 1H-NMR measurements.