Bilayer nanofibers loaded with Malva sylvestris extract for enhanced wound healing applications

Abstract

Addressing the challenges of wound care requires accurate dressing selection. The combination of collagen with nanofibers (NFs) enhances its properties, improving cellular recognition. Multi-layered nanofibrous systems, particularly those with Polycaprolactone (PCL), offer higher mechanical attributes and prolonged substance release. We fabricated four types of nanofibrous bilayer mats (NBMs) using electrospinning (EN), each composed of an active layer containing a mixture of PCL and collagen loaded with and without Malva sylvestris (MS) extract, and an inactive layer with only PCL. The resulting bilayers were neat PCL/PCL-Collagen (PCLC), PCL/PCLC-5% MS, PCL/PCLC-10% MS, and PCL/PCLC-15% MS. Morphological and mechanical properties, porosity, water vapor transmission rate (WVTR), swelling rates, drug release profiles, cytotoxicity, cell attachment, and cytoprotective effect of bilayers were evaluated. FE-SEM imaging revealed smooth and filamentous mats without any beads, with Fiber diameter average (FDA) ranging from 128 ± 41 nm to 140 ± 51 nm. WVTR values of the NFs were comparable to commercial dressings like Tegaderm, Bioclusive, and Op Site. The mats demonstrated significant liquid uptake capacity, indicating their potential to handle wound exudate. They exhibited prolonged extract release, ensuring a sustained supply. All mats showed excellent blood compatibility, with our MS-loaded NBMs displaying rapid blood clotting times, essential for effective wound closure. FE-SEM images confirmed robust cell adhesion and spreading on both loaded and unloaded mats. The study underscored the potent cytoprotective effects of MS extract, in both free and encapsulated forms. The dose-dependent increase in cell viability suggests its potential in mitigating oxidative stress-induced cellular damage. The MTT (4,5-dimethyl- 2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) assay revealed that encapsulating MS extract in bilayer NFs significantly improved cell viability at 48 and 72 h, surpassing free MS extract treatment.