Bacterial nanocellulose membranes for codelivery of carvacrol and thymol: physico-chemical characterization and in vitro studies

Abstract Skin wounds represent a worldwide problem. Biopolymers have been attracting interest for healthcare products toward wound dressing. Among these biopolymers, bacterial nanocellulose membranes (BNC), with its tridimensional and branched nano- and microfibrillar structure, are attractive. Despite that, BNC present no antimicrobial activity. Thus, the incorporation of the monoterpenes Carvacrol (Car) and Thymol (Thy) - which present antimicrobial and healing properties - toward the improvement of skin wound healing, consists of an appealing approach. This research aimed to produce and characterize nanocellulose membranes containing carvacrol and/or thymol, and investigate their release behavior, cytotoxicity and antimicrobial properties. BNC/Car, BNC/Thy and BNC/Car-Thy membranes were produced at doses of 0.1 and 1.0 mg/cm 2 . The natural components incorporation into the nanocellulose did not interfere neither on ultra-structure nor on its physic characteristics. Release experiments showed a burst release between 2–4 h with sustained release till 24 h, reaching around 80% of the initial amount of the incorporated monoterpenes. Studies with fibroblast and keratinocytes indicated no cytotoxicity and that cells could proliferate over the BNC/Car-Thy membranes. Microbiological studies suggested some antimicrobial potential of the BNC doped with Car and Thy. This innovative biomaterial has the potential for health care products.