Multi-drug delivery systems constructed from a basic polymeric scaold, and which have the ability to target a variety of biomedical applications, can streamline the development of nanomedicine to provide both environmental and economical relief. Herein, amphiphilic ABA-triblock copolymers are synthesized and assembled sequentially into micelles and nanogels as drug delivery systems following a thorough evaluation on advanced in vitro models to explore their potential for the treatment of cancer and bacterial infections. Short blocks of -methyl--allyloxycarbonyl-,-dioxan--one (MAC) are oli-gomerized from PEGk and thereafter functionalized with dihydroxyphenyla-lanine (dopa)-functional thiols using thiol-ene coupling (TEC) click chemistry. The copolymers self-assemble into well-defined micelles in aqueous solution and are further formulated into nanogels via UV-induced TEC. The resulting spherical micelles and nanogels are stable nanoparticles, with sizes ranging between  and  nm. The nanogels are found to be non-toxic to a panel of cell lines and mask the toxicity of the potent drugs until their release. The nanogels would be superior to micelles for the elimination of cancer cells supported by both D cell culture and a D spheroid model. The opposite conclusion could be drawn for bacteria inhibition.

For the stabilization of complex bone fractures, tissue adhesives are an attractive alternative to conventional implants, often consisting of metal plates and screws whose fixation may impose additional trauma on the already fractured bone. This study reports on the synthesis and evaluation of activated dopamine derivatives as primers for fiber-reinforced-adhesive patches in bone-fracture stabilization strategies. The performance of synthesized dopamine derivatives are evaluated with regard to the adhesive shear strength of formed bone patches, as well as cell viability and surface properties. Dopamine-derived primers with methacrylamide, allyl, and thiol functional groups were found to significantly increase the adhesive shear strength of adhesive patches. Furthermore, deprotonation of the primer solution was determined to be essential in order to achieve good adhesion. In conclusion, the primer solutions that were found to give the best adhesion were the once where dopa-thiol was used in combination with either dopamethacrylamide or dopa-allyl, resulting in shear bond strengths of 0.29 MPa.

Since extraction of the naturally occurring mussel-foot proteins is expensive and time-consuming, routes towards synthetic analogues are continuously being explored. Often, these methods involve several protection and deprotection steps, making the synthesis of synthetic analogues time-consuming and expensive as well. Herein, we show that UV-initiated thiol-ene coupling between a thiol-functional dopamine derivative and an allyl-functional aliphatic polycarbonate can be used as a fast and facile route to dopa-functional materials. Different thiol-to-allyl ratios and irradiation protocols were used and it was found that nearly 50% of the allyl groups could be functionalized with dopa within short reaction times, without the need of protecting the catechol. It is also demonstrated herein that the dopa-functional polymers can be used to form self-healing gels through complexation with Fe3+ ions at increased pH.

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.

Reaktioner mellan tioler och omättade kemiska föreningar utgör ett mångsidigt och effektivt redskap inom polymersyntes. I denna avhandling har begreppet tiol-en kemi varit centralt och kemin har använts för syntes av såväl väldefinierade hydrogeler som dopa-funktionella material. Dessa material har sedan utvärderats mot biomedicinska tillämpningar såsom hydrogeler, primers för fixering av benfrakturer, självläkande geler och kontrollerad läkemedelsleverans.

Tiol-en-kemi har i denna avhandling använts för att framställa väldefinierade hydrogeler som sedan utvärderats med avseende på hur strukturen påverkar egenskaper såsom svällningsgrad, styvhet och nedbrytningshastighet. Det visade sig att alla dessa egenskaper är relaterade till varandra och att lösare tvärbundna hydrogeler uppvisar högre svällning, lägre styvhet och högre nedbrytningshastigheter.

Marina musslor har en exceptionell förmåga att fästa mot olika ytor och på grund av detta har det visats en hel del intresse för dopa-funktionella material genom åren. På jakt efter en primer för att öka vidhäftningen hos benlim proponerades därför föreningar med dopafunktionella grupper. Det visade sig att dopaminderivat kunde förbättra vidhäftningen mot ben och det visade sig även att tillsats av natriumhydroxid var viktigt för att uppnå god vidhäftningsförmåga. Den starkaste vidhäftning uppnåddes när derivat med tiol och omättade bindningar användes i kombination.

Syntes av dopafunktionella material involverar ofta flera reaktionssteg och en förenklad syntesväg är därför att eftersträva. UV-initierad tiol-en-kemi undersöktes därför som en möjlig syntesväg för att framställa dopafunktionella polymerer. Polymererna visade sig ha självläkande egenskaper vid komplexbildning med järnjoner.

Slutligen användes denna syntesväg för att framställa blocksampolymerer. Dessa blocksampolymerer användes sedan för att bilda miceller med lovande resultat vid utvärdering för leverans av läkemedel mot bröstcancer.

The branched architectures of dendritic polymers display a large number of end groups, and dendrimers have been extensively evaluated as scaffolds in a large array of research fields, including biomedicine and nanotechnology. From the number of potential applications that require advanced crosslinked films, dendritic macromolecules are attractive as scaffolds that deliver on promising crosslinked three-dimensional (3D) networks. This review briefly covers a description of the family of functional dendritic polymers, ranging from dendrimers and dendrons to hyperbranched polymers and dendritic linear hybrids. The review also contains a detailed report on proposed chemistries for the exploitation of dendritic materials as scaffolds in the field of advanced networks.

In this work, photo-induced thiol-ene coupling (TEC) was used to produce well-defined poly(ethylene glycol) (PEG)-based hydrogels. PEGs of four different molecular weights (2k, 6k, 10k, and 20k) were functionalized with G1-allyl dendrons using anhydride chemistry to produce tetra-functional TEC crosslinkable PEGs. The tetra-functional PEGs were subsequently crosslinked with a tri-functional thiol in ethanol to form hydrogels. The synthesized hydrogels were characterized with respect to swelling behaviour, rheological properties and hydrolytic degradation. It was found that the molecular weight of the PEG chain greatly influences the final properties of the hydrogel, where a higher molecular weight of PEG gives an increased weight swelling ratio from 240% for PEG-2k hydrogels to 1400% for PEG-20k hydrogels, as well as decreased elastic moduli, with Young's moduli ranging from 106 MPa to 6 MPa, for PEG-2k and PEG-20k hydrogels, respectively. It was also found that the hydrolytic stability in alkaline conditions (pH 10) decreased when the molecular weight of PEG in the hydrogels increased.