Poly(vinyl alcohol)/Pullulan Composite Hydrogels as a Potential Platform for Wound Dressing Applications

Area of Science:

• Materials Science
• Biomedical Engineering
• Polymer Chemistry

Background:

• Hydrogels are effective wound dressings due to their high fluid retention and ability to create a moist healing environment.
• Poly(vinyl alcohol) (PVA) and pullulan (PULL) are biocompatible polymers suitable for hydrogel formation.

Purpose of the Study:

• To investigate the properties of physical hydrogels formed from PVA and PULL mixtures.
• To evaluate the impact of Laponite clay addition on PVA/PULL hydrogel characteristics.
• To assess the potential of these hydrogels for controlled drug delivery in wound healing applications.

Main Methods:

• PVA/PULL hydrogels were prepared using the freezing/thawing method in various weight ratios.
• Hybrid hydrogels were synthesized by incorporating 0.5% Laponite RD.
• Characterization included scanning electron microscopy (SEM), viscoelastic property analysis, swelling studies, and in vitro drug release of neomycin sulfate.

Main Results:

• SEM confirmed the porous inner structure of the hydrogels.
• Hydrogel composition significantly influenced viscoelastic properties and network strength.
• Swelling followed a quasi-Fickian diffusion mechanism under physiological conditions (37 °C, pH 7.4).
• Drug release kinetics were best described by the Peppas-Sahlin model for polymer hydrogels and the Korsmeyer-Peppas model for hybrid polymer/clay hydrogels.

Conclusions:

• PVA/PULL hydrogels, particularly those containing 40-60% PULL without clay, exhibit suitable properties for wound dressing applications.
• These hydrogels demonstrate potential for the controlled release of therapeutic agents at wound sites under physiological conditions.
• The addition of Laponite clay modifies drug release mechanisms, suggesting tailored applications.