Encapsulation and release of Zafirlukast from electrospun polyisobutylene-based thermoplastic elastomeric fiber mat

Electrospun fiber mats from poly(alloocimene-b-isobutylene-b-alloocimene) thermoplastic elastomer

“…XPS detected only carbon signals and traces of oxygen on the surface of the fibers ( Figure S4 in Supporting Information). This agreed with earlier findings [13] therefore we concluded that the PEG was fully embedded into the fibers. Soaking in water for 2 days extracted the PEG from the AIBA/PEG fibers, similarly to that shown for Arbomatrix/PEG [4].…”

“…Cell viability was identical in the presence and in the absence of the mat. This is consistent with the bioinertness shown for PIB-based TPEs [13].…”

“…The static WCA was 121_ ± 3_, while the dynamic WCA were 133_ ± 2_ (advancing) and 27_ ± 5_ (receding), signifying the segregation of the polar PEG to the surface ( Figure S6). Comparable results were shown for Arbomatrix/PEG 9 fibers previously [13]. It was shown for PIB-based TPEs that surface rearrangement could take place in an aqueous environment [19], due to chain mobility of the rubbery matrix.…”

“…Figure 1 shows a representative SEM image of the electrospun fiber mat. The fibers assumed a dumbbell-shaped cross-section, as was reported earlier for Arbomatrix [12,13]. Reneker et al [18] explained that the dumbbell-shape can form when the diametrically opposite parts of the polymer skin forming during electrospinning come into contact, yielding two small parallel tubes connected by a "bar".…”

“…The ratio of Arbomatrix to PEG was chosen to be 80/20 wt/wt based on scouting experiments. We successfully encapsulated a model drug, Zafirlukast, into the fibers, and demonstrated greater than 90% release [13]. Although electrospinning can produce ultrafine fibers, the mean fiber size for Zafirlukast-loaded Arbomatrix/PEG fibers was larger (4.197 (±0.580) mm).…”