Multilayer nanofibrous patch comprising chamomile loaded carboxyethyl chitosan/poly(vinyl alcohol) and polycaprolactone as a potential wound dressing.

Electrospun multilayer nanofibrous patches with a new design were developed using poly(ε-caprolactone) (PCL) and chamomile loaded carboxyethyl chitosan (CECS) and polyvinyl alcohol (PVA) in which chamomile extract was used as an antioxidant/antibacterial agent. To prepare an aqueous solution (water as solvent) from chitosan and PVA along with the herbal extract, chitosan was modified to CECS by Michael reaction and proved by 1H NMR and FTIR. Multilayer patches composed of a hydrophilic chamomile loaded CECS/PVA nanofibrous layer to be in contact with the wound and a hydrophobic PCL nanofibrous layer to provide the strength were electrospun. Hybrid nanofibers made of PCL and chamomile/CECS/PVA were electrospun as cohesion promoter between the hydrophilic and hydrophobic layers due to their different chemical nature and weak cohesion. SEM showed continuous, smooth, and bead-free nanofibers with excellent compatibility between polymers and chamomile. The mats exhibited satisfactory tensile strength (8.2-16.03 MPa), and antioxidant characteristics (6.60-38.01%). Furthermore, 15, 20, and 30 wt% chamomile loaded mats possessed high antibacterial efficiency, which enhanced with increasing chamomile content. The results demonstrated that chamomile sustained-release significantly controlled by Fickian-Diffusion mechanism. MTT assay revealed proper cell viability for all mats except one contained 30 wt% chamomile.