# Electrospinning of Chitosan for Antibacterial Applications--Current Trends
## 7 Application Fields of Electrospun Chitosan Nanofibers and Chitosan Derivatives
### Biomedicine
#### 7.4.1 Wound Dressings
Electrospun scaffolds with several layers have also been developed for wound healing. The sophisticated structure of the first layer of PCL or PCL/cellulose acetate provided mechanical support, while the second layer of the chitosan/PEO blend came into direct touch with the wound surface. These scaffolds were biocompatible with fibroblast cells, had 80% porosity, strong vaporpermeability, and could expand by up to 370% without losing mechanical or structural features, making them ideal as resorbable dressings for thick exudative wounds [197]. The wound treatment and antibacterial performance of chitosan nanofibers can be improved by infusing inorganic nanoparticles within the fibers. The incorporation of metallic nanoparticles is also useful for the function of various medical textiles. Biosensors and drug carriers are examples of textiles used for diagnostic or therapeutic applications, where the metals included in nanofiber scaffolds can produce electric or magnetic fields essential for the functionality of wearable smart textiles or the direction of cell migration. As a matter of fact, hyperthermia therapy is only possible when the material can be heated, which can be achieved by loading chitosan nanofibers with magnetic nanoparticles, such as Fe\({}_{3}\)O\({}_{4}\)[198]. Since the addition of bactericidal agents can substantially improve the antibacterial capacity of nanofibrous scaffolds, silver nanoparticles (AgNPs) on chitosan/PEO membranes showed substantial efficacy against _E. coli_[199]. Chitosan/gelatin nanofibers containing AgNPs also produced positive results [200]. Nanofibers used for passive antibacterial wound healing were prepared by encapsulation of delaminated Ti\({}_{3}\)C\({}_{2}\)T\({}_{z}\) (MXene) flakes within chitosan nanofibers via electrospinning. Antibacterial experiments on biocompatible crosslinked Ti\({}_{3}\)C\({}_{2}\)T\({}_{z}\)/chitosan composite fibers against _S. aureus_ and _E. coli_ reduced the bacterial colonization by 62% and 95%, respectively, after 4 h, revealing the electrospun Ti3C2 Tz/chitosan nanofibers as viable non-toxic candidate materials for wound healing applications [201]. Burns are among the most frequent and serious injuries that may cause skin function damage. The protective properties of the skin are lost in high-degree burn injuries, causing heat-induced skin degradation and the formation of scarring. The scar area is a wet, alkaline, protein-rich, non-vascular environment devoid of immune cells. As a result, it is thought to be an ideal habitat for the development of bacteria, resulting in infections that spread on the wound surface. Although topical antibiotic therapy with medicines does not sterilize wounds, it does decrease the number of germs in the tight tissue underneath the scar to a level where the host immune system can manage them [201]. Debridement is one of the therapy options for scar removal. To minimize moisture loss, prevent microbial infection, and improve wound healing, the skin's surface must be covered with an appropriate membrane after surgical excision of infected tissue. Nanofibrous films are one of the most effective wound dressing options. A number of antibacterial potential films were electrospun, including pure PVA, chitosan/PVA, and drug-loaded chitosan/PVA at different concentrations. [PERSON] et al. [202] examined the capacity to prevent microbial penetration of the different nanofiber materials by using an open test tube containing nutritional broth without any covering material as the positive control, while another tube, which was closed with a densely packed cotton ball, served as negative control. The positive control tube's intense turbidity showed that the nutrient broth medium was appropriate for microbial growth, whereas the negative control tube's absence of turbidity indicated that sterile conditions were maintained throughout the experiment. Microorganisms penetrating through the film into the test tube induced microbial growth and increased the turbidity of the medium throughout the tests.