Physico-mechanical Properties of Electrospun Poly(vinyl alcohol)/Alginate Fibers

摘要

Fibrous alginate wound dressings are popular due to its ability to absorb a large amount of wound exudates. However, these alginate fibers are fairly large, which limits their liquid absorption rate. To further enhance the dissolution properties of the current available alginate fibrous dressings, we electrospun nanofibers using blend solutions of polyvinyl alcohol (PVA)/alginate at various blend ratios, with the aims to (1) optimize PVA/alginate compositions for electrospinnability, and to (2) correlate their physico-mechanical properties and dissolution rates with fiber compositions. Our results suggested that the optimal electrospinning conditions for all PVA/alginate fibers include a flow rate of 10 μL/min, a voltage of approximately 14 kV, and a distance of 10 cm from the tip of the needle to the collector plate. Effects of PVA/alginate compositions on fiber distribution after one hour of electrospinning were evaluated by thickness profiles of the fiber mats. Thickness profiles of the PVA/alginate fiber mats showed no significant difference on the overall deposition size of the fiber mats. Using fibers containing 2 wt% of alginate, tensile properties showed an increase of average elastic moduli from 87.2 MPa to 116.8 MPa when increasing alginate compositions in PVA/alginate fibers from 90/10 to 80/20. The corresponding fiber formulations showed an increase of average tensile strength from 4.2 MPa to 5.1 MPa. The increases in fiber stiffness and tensile strength of the alginate-containing fibers were accompanied by the decrease of average elongation to failure of the fibers. In general, our study provides scientific understandings on the feasibility studies of electrospun alginate fibers for the potential use of wound dressing materials. More importantly, by blending alginate with PVA through electrospinning, we enable the possibilities of partitioning drugs in blend fibers with tailored dissolution rates for release kinetics that serve the purpose of controlled releases in advanced wound dressings.