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 H 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.