Thiol-Ene CHemistry and Dopa-Functional Materials towards Biomedical Applications

Sammanfattning: Thiol-ene chemistry is versatile and efficient and can be used as a powerful tool in polymer synthesis. In this thesis, the concept of thiol-ene chemistry has been central, where it has been explored as a tool for the synthesis of well-defined hydrogels and dopa-functional materials towards biomedical applications; such as hydrogels, primers for adhesive fixation of bone fractures, self-healing gels, and micelles for drug-delivery.Using thiol-ene chemistry, well-defined hydrogels were realized in order to study how the structure influences properties such as swelling, stiffness and hydrolytic degradation. It was found that all these characteristics are related to each other, as a more loosely crosslinked hydrogel experiences higher swelling, lower stiffness and higher degradation rates.Dopa-functional materials have gained a lot of interest throughout the years due to the remarkable adhesive properties they possess in wet environments. In the pursuit of new primers towards thiol-ene functional crosslinked bone adhesives, compounds with dopa moieties were proposed. Primers derived from dopamine were found to enhance the adhesion towards bone, and it was concluded that addition of NaOH was essential to achieve good adhesion. The strongest adhesion was achieved when thiol and ene-functional primers were used in combination. Most synthetic routes to dopa-functional polymers involve several protection and deprotection steps and a more simplistic synthetic route is therefore desired. The possibility of using UV-initiated thiol-ene chemistry to produce dopa-functional polymers was therefore investigated. The resulting polymers were shown to exhibit self-healing properties upon complexation with Fe3+ ions.Finally, the developed synthetic route was used to produce dopa and allyl-functional triblock-co-polymers. These triblock-co-polymers were then used to form micelles and evaluated as drug-delivery vehicles for the cancer-drug doxorubicin. The micelles were found to have high drug-loading capacities and slow release profiles and showed promising results when evaluated against breast-cancer cells.