## 5 Nanoformulations for Wound Healing
### Electrospun Nanofibers Loaded with Phytochemicals
potent drug carrier due to its hydrophilicity, swelling ability, biocompatibility, and potential to functionalize with other polymers. CS has been identified as one of the most promising biopolymers for medical devices and implants, tissue engineering, and drug delivery applications [80; 81; 82; 83; 84]. Baialein (BAC) is a herbal compound with both antioxidants and antimicrobial effects, originating from _Scutellaria bacialensis_ [PERSON]; to reinforce its activity, BAC-modified CS was molded into nanofibers via the electrospinning process and studied for its wound healing potency. From the results, the electrospun nanomats presented desirable antioxidant and antimicrobial properties, which improved the wound healing process. These nanomats can promote wound healing while meeting clinical standards due to their mechanical properties. Furthermore, the grafting process improves the solubility of CS, which is important for drug delivery applications [85]. Most frequently, CS is mixed with other polymers to present improved properties. Royal jelly, a honeybee secretion, exhibits various biological activities and important antibacterial and anti-inflammatory properties; therefore, [PERSON] et al. developed nanofibrous dressings based on PVA/CS impregnated with royal jelly. Nanofibers with sizes of around 200-300 nm demonstrated hydrophilicity and vapor permeability, significant parameters for wound healing. Furthermore, the royal-jelly-loaded nanofibers were able to halt the microbial growth of _Staphylococcus aureus_ and _Escherichia coli_. Given their improved antibacterial performance, these nanofibrous dressings have great potential in combating wound infections [86]. Similar wound dressings of PVA/CS were designed by electrospinning to inhibit infection and promote healing. The authors examined extracts from _Thymus vulgaris_ and _Zingiber officinal_ incorporated into a nanofibrous mat with a diameter size of around 380 nm. The fabricated dressings demonstrated a porous surface, enhanced wettability properties, and liquid absorption capacity. Moreover, the nanofibers exhibited antioxidant properties and increased antibacterial activity against _S. aureus_ and _E. coli_ strains, while promoting wound healing in bacteria-infected rats [87]. Electrospun bilayer nanofibers comprising a CS/PVA active layer and PCL inactive back layer were fabricated to analyze the potential of pomergnate flower extract delivery. Nanofibrous dressings with diameter sizes of around 400 nm exhibited liquid absorption characteristics, wound healing effects, and, most significantly, antimicrobial performance against strains of _S. aureus_ and _P. aeruginosa_. The extract-loaded nanofibers showed accelerated wound healing of almost 88%  
Figure 5: The fibrous morphology of wound dressings based on PLLA, PVA, and chitosan (CS), with and without _Hypericum perforatum_ L. (HP). SEM micrographs and diameters of PLLA/PVA/CS wound dressings without HP extract, with 2.5% HP extract, and with 5% HP extract. Reprinted under open access Creative Common CC BY License, MDPI (2023) [82]. within two weeks [88]. Alginic acid (ALG) and its derivatives are widely used for wound healing and anti-infective systems, since they have been found to be effective against microbial growth inhibition. Therefore, to enhance its physicochemical properties, ALG has been blended with various polymers. In a recent study, nanofibrous mats from PVA and ALG loaded with natural extracts from _Lawsonia intermis_ (_LI_) and _Scrophularia striata_ (_SS_) were studied for their wound healing potency. The biocompatible matrices exhibited antimicrobial activity, especially those with the extracts. Furthermore, in vivo studies demonstrated that the nanofibers promoted wound healing and tissue regeneration [89]. Chlorogenic acid is 5-caffeoylquinic acid, widely found in fruits, vegetables, and plants, exhibiting anti-inflammatory, antidiabetic, and wound healing properties, among others.