Antimicrobially active gelatin/[Mg-Al-CO3]-LDH composite films based on clove essential oil for skin wound healing

Abstract

In this study, gelatin, a biocompatible, collagen-derived protein, was combined with clove essential oil (CEO) and hydrotalcite ([Mg-Al-CO3]-LDH) nanoplates (D ∼ 100 nm) as an attempt to develop new antimicrobial wound dressings. CEO-loaded gelatin films covering different hydrotalcite contents (0.5–5.0 wt.%) were obtained by solution casting and characterized by light microscopy, FTIR and UV–vis spectroscopies, tensile and optical tests, water contact angle (WCA) determinations, and disc diffusion assays. CEO formed emulsified morphologies with gelatin over the entire hydrotalcite content range. Hydrotalcite contents larger than 2.5 wt.% were key for retain CEO in the gelatin matrix, which ensured antimicrobial activity for the films against Staphylococcus aureus and Escherichia coli. The UV barrier and mechanical properties of gelatin were significantly increased by CEO and further sustained upon hydrotalcite addition. All the composite films were regarded as hydrophilic materials (WCA < 75°), which was a preliminary requirement for their in vivo biocompatibility. The films were nontoxic towards HeLa cells, with cell viabilities above 70 %, as determined by MTT assay. These outcomes point out a simple way of using hydrotalcite to produce functional, biocompatible composites based on gelatin and clove essential oil for cutaneous wound healing and other biomedical applications.