Fabrication and characterization of Pluronic modified poly(hydroxybutyrate) fibers for potential wound dressing applications

• Poly(hydroxybutyrate) fibers were hydrophilized by blending with Pluronic F-108 (PHB-PF).
• Electrospun PHB-PF fibers demonstrated enhanced water wettability and swelling properties.
• PHB-PF fibers demonstrated higher stretchability and reduced brittleness.
• PHB-PF fibers facilitated enhanced and rapid hemostasis.
• Doxycycline loaded PHB-PF fibers demonstrated antibacterial activity and potential as a wound dressing.

Electrospun poly(hydroxybutyrate) (PHB) fiber meshes have shown some success in wound dressing applications, however, their use is limited by their high hydrophobicity and brittle nature. In this study we investigated the effect of hydrophilization of electrospun PHB fibers by blending with Pluronic F-108 (PF) for use as a wound dressing material. Blending of PHB with different concentrations of PF (0.5%PF-PHB and 1.0% PF-PHB) before electrospinning led to a significant increase in the water wettability and swelling properties of fibers as compared to pristine PHB fibers. Further, it was observed that though the tensile moduli of PF blended PHB fibers were relatively lower as compared to PHB fibers, they show higher resistance to failure measured in terms of strain to failure and energy to failure. Moreover, PF blending significantly improved the in vitro blood clotting rate on PHB fibers when compared to control PHB fibers. Furthermore, the fabricated fiber systems were found to be cytocompatible and supported adhesion of fibroblasts in vitro. Finally, it was demonstrated that the PF blended fiber systems were suitable for the encapsulation of an antibiotic (doxycycline) to render them with antibacterial properties. Taken together, this study demonstrates that PF blending can be used to significantly improve properties of PHB fibers for wound dressing applications.