Nowadays, antibiotic-loaded biomaterials have been widely
used
in wound healing applications. However, the use of natural extracts
has come into prominence as an alternative to these antimicrobial
agents in the recent period. Among natural sources,Cissus quadrangularis(CQ) herbal extract is used
for treatment of bone and skin diseases in ayurvedic medicine due
to its antibacterial and anti-inflammatory effects. In this study,
chitosan-based bilayer wound dressings were fabricated with electrospinning
and freeze-drying techniques. CQ extract-loaded chitosan nanofibers
were coated on chitosan/POSS nanocomposite sponges using an electrospinning
method. The bilayer sponge is designed to treat exudate wounds while
mimicking the layered structure of skin tissue. Bilayer wound dressings
were investigated with regard to the morphology and physical and mechanical
properties. In addition, CQ release from bilayer wound dressings andin vitrobioactivity studies were performed to determine
the effect of POSS nanoparticles and CQ extract loading on NIH/3T3
and HS2 cells. The morphology of nanofibers was investigated with
SEM analysis. Physical characteristics of bilayer wound dressings
were determined with FT-IR analysis, swelling study, open porosity
determination, and mechanical test. The antimicrobial activity of
CQ extract released from bilayer sponges was investigated with a disc
diffusion method. Bilayer wound dressings’in vitrobioactivity was examined using cytotoxicity determination, wound
healing assay, proliferation, and the secretion of biomarkers for
skin tissue regeneration. The nanofiber layer diameter was obtained
in the range of 77.9–97.4 nm. The water vapor permeability
of the bilayer dressing was obtained as 4021 to 4609 g/m2day, as it is in the ideal range for wound repair. The release of
the CQ extract over 4 days reached 78–80% cumulative release.
The release media were found to be antibacterial against Gram-negative
and Gram-positive bacteria.In vitrostudies showed
that both CQ extract and POSS incorporation induced cell proliferation
as well as wound healing activity and collagen deposition. As a result,
CQ-loaded bilayer CHI-POSS nanocomposites were found as a potential
candidate for wound healing applications.