Vancomycin-loaded SF/CS/PEO nanofibers containing ZnO and TiO2 for controlled drug delivery and hemostatic applications

Uncontrolled hemorrhage resulting from traumatic injuries is a primary reason for mortality and is often accompanied by a risk of wound infection. Therefore, the development of wound dressings that can simultaneously provide rapid hemostasis and effective antimicrobial activity is crucial. In this study, silk fibroin (SF), chitosan (CS), and poly(ethylene oxide) (PEO) electrospun nanofibers were prepared and loaded with vancomycin (VAN). To further enhance hemostatic and antimicrobial performance, zinc oxide (ZnO) or titanium dioxide (TiO₂) nanoparticles were individually incorporated into the VAN-loaded nanofibrous matrix. To the best of our knowledge, this is the first report demonstrating the combined effects of VAN and ZnO or TiO₂ within an SF/CS/PEO nanofibrous matrix, achieving hemostatic activity, antibacterial efficacy, and controlled drug release in a single platform. The nanofibers were stabilized by cross-linking with glutaraldehyde vapor and then characterized in terms of morphology, drug-polymer and polymer-polymer interactions, thermal stability, drug loading efficiency, and drug release properties. Biocompatibility, antimicrobial activity, hemocompatibility, and blood clotting time were evaluated in vitro . In addition, the hemostatic performance of the nanofibers was evaluated using a Sprague-Dawley rat tail amputation model. All nanofibers exhibited uniform, bead-free morphologies and high VAN loading efficiencies (92-98%), and sustained drug release profiles were observed for up to 168 h following an initial burst release. In vitro results showed that all nanofibers had potent antibacterial activity against Gram-positive bacteria, negligible cytotoxicity toward human dermal fibroblasts, and had hemolysis levels below the acceptable safety threshold. In an in vitro blood clotting study, VAN-loaded nanofibers containing ZnO nanoparticles demonstrated the fastest hemostatic activity, reducing coagulation time to approximately 4.5 min, while the other nanofibers also showed a notable improvement over the control group, reducing coagulation time to approximately 5.0-5.4 min. In an in vivo hemostatic study, nanofibers, particularly those loaded with VAN and containing ZnO, significantly reduced bleeding amount and exhibited hemostatic performance comparable to that of the commercial HemCon® product. These findings demonstrate that VAN-loaded and ZnO- or TiO₂-containing SF/CS/PEO electrospun nanofibers represent a promising multifunctional wound dressing for the management of traumatic bleeding, offering rapid hemostasis, infection prevention, and sustained therapeutic delivery.