Novel biofunctional polyester nanofibers

Abstract

In recent years, nanofibers have gained much attention in different scientific fields due to their potential applications. Increased interest arise due to their promising properties such as high surface-to-volume ratio, high encapsulation efficiency, high loading capacity and physical resemblance to the 3D structure of extracellular matrix. As health applications, nanofibers can be used in drug delivery systems, wound healing materials, tissue engineering and enzyme immobilization. Nanofibers can made via electrospinning, phase separation and self-assembly. Electrospinning is widely used because of its easiness and effectiveness. Obtained nanofibers can be functionalized with ‘clickable’ functional groups to suit the intended goal. This thesis focused on obtaining azide containing clickable biofunctionalizable nanofibers. In this study, a novel azide containing carbonate monomer was synthesized to obtain copolymers that were used as a precursor for electrospinning. Lactide was chosen because of its biodegradability and good mechanical properties during electrospinning. Azide containing carbonate monomer was used for functionalization of the nanofibers. Initially, efficient functionalization of nanofibers was probed using a dibenzocyclooctyne (DIBO) containing a fluorescent dye. It was deduced that the extent of functionalization of nanofibers could be tuned by amount of azide groups in the copolymers. DIBO-containing biotin was attached to the azide containing nanofibers via azide-alkyne click chemistry. Thereafter, extravidin was immobilized onto biotin functionalized nanofibers due to the high affinity of extravidin for biotin. Importantly, metal or metal-based complexes weren’t used in this work for neither polymerization nor functionalization because of the potential toxicity of metals to the cells.