LAUSR

Hydrophobically modified guar gum (HMG) was prepared by microwave-assisted polycondensation of naturally abundant guar gum (GG) and dimer acid (DA) following green chemistry principles. HMG was blended with polyvinyl alcohol (PVA) along with gentamicin sulphate (a hydrophilic antibacterial drug) or amoxicillin (a hydrophobic antifungal drug) to obtain drug-loaded films. The two films were characterized by FTIR spectroscopy, X-ray diffraction analysis and scanning electron microscopy. Water absorbency, drying time (water holding time) and vertical wicking time were also determined. The results suggest that the drug-loaded films, HMGA with amoxicillin and HMGG with gentamicin sulphate, could retain moisture for 5–7 h and easily absorb wound exudates. Drug release data were analysed using first-order, Higuchi, Hixson–Crowell and Korsmeyer–Peppas kinetic models and reveal that the HMG-based films exhibit good drug delivery efficiency for hydrophobic as well as hydrophilic drugs. The results of agar diffusion method indicate the two films to exhibit significant resistance toward bacterial (Staphylococcus aureus and Escherichia coli) and fungal (Candida albicans) growth. In vivo wound healing studies on Wistar albino rats show almost full wound closure within 15 days. These results demonstrate the HMG-based drug-loaded films to be promising candidates to serve as biodegradable wound dressing.