Comparison of the Release of Aloe vera Extracts from Poly(Vinyl Alcohol) Electrospun Fibers and Hydrogel Films for Wound Healing Applications

摘要

Aloe vera extracts, consisting of active compounds that decrease pain and inflammation and stimulate skin growth and repair, are selected as a drug model in this work. Polyvinyl alcohol (PVA) was used as base material. Release profiles of aloe vera extracts from PVA electrospun fibers were compared to those from PVA hydrogel films prepared by freezing/thawing method. This method provided a physical crosslinked polymer. The concentration of PVA solution used for electrospinning and hydrogel preparation was 10% wt with different contents of aloe vera extracts (0, 30, 50, 70 and 90% w/w). The properties of electrospun fibers and hydrogel films were evaluated in terms of morphology, chemical structure, swelling behavior and release profiles. The morphological properties of electrospun fibers and hydrogel film were observed by SEM. Electrospun fibers were smoothly round, high surface area, and non-woven, while hydrogel film possessed rough surface and was covered with porous. Fourier transform infrared spectroscopic measurement exhibited the existence of relevant functional groups of both PVA and aloe vera extracts. The results showed relevant functional groups of aloe vera extracts in both electrospun fibers and hydrogel film. The release of aloe vera extracts from both electrospun fibers and hydrogel film was evaluated in acetate buffer pH 5.5 at 25 °C and was monitored by UV-vis spectroscopy. It was revealed that as the content of aloe vera increased, the amount of aloe vera extracts released from electrospun fibers decreased. This result contrasts with the release of aloe vera from hydrogel film that increased when the content of aloe vera increased. It was also noticed that the amount of aloe vera extracts released from electrospun fibers was more than that from hydrogel films during 600 minutes. The results also showed that the releasing rate of aloe vera from electrospun fibers was faster than that from hydrogel films. This is probably because electrospun fibers had much higher surface area than that of hydrogel film thus, the release was faster.