Potential wound dressings from electrospun medicated poly(butylene-adipate-co-terephthalate)/poly-(ε-caprolactone) microfibers

Wound dressings are alternatives for the treatment of burn injuries because they facilitate the recovery of the wounded area, and they still allow the incorporation of bioactive agents in their structure for further release in specific regions of the body. This work evaluated the potential application of monoaxial electrospun poly(butylene-adipate-co-terephthalate) (PBAT)/poly-(ε-caprolactone) (PCL)-based microfibers, loaded with silver sulfadiazine (SS), as a wound dressing device. The fibers were characterized by Infrared Fourier Transform (FTIR), X-Ray Diffraction (X-RD), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TG/DTG), mechanical properties, Scanning Electron Microscopy (SEM), wettability, controlled release, and antimicrobial activity. SEM results indicated the production of fibers with high bead content, especially for the fibers containing 20% of SS (PBAT/PCL-20). The diameter of the fibers ranged from (3.113 ± 0.4320) µm (PBAT/PCL-0) to (0.5910 ± 0.1380) µm (PBAT/PCL-10), and both SS concentrations led to beads of ~7 µm of diameter. XRD and DSC results confirmed that the bead formation was a concentration-dependent factor, due to the higher heterogeneous nucleation, and it increased the crystallinity of the fibers from 31.23% (PBAT/PCL-0) to 48.07% (PBAT/PCL-20). Antimicrobial assays confirmed that the efficiency of these fibers against Escherichia coli and Staphylococcus aureus depended on the drug concentration. The release assays indicated a biphasic release, characterized by an initial fast release followed by a controlled and sustained release, lasting for over 4 days. This type of release is attractive for wound treatment because it promotes initial pain relief, and the following controlled step sustains the treatment for longer periods, enhancing the healing of the wounded area.