Development of Cissus quadrangularis-Loaded POSS-Reinforced Chitosan-Based Bilayer Sponges for Wound Healing Applications: Drug Release and In Vitro Bioactivity

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 and in vitro bioactivity 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 vitro bioactivity 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 vitro studies 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.

Anticancer efficacy of lupeol incorporated electrospun Polycaprolactone/gelatin nanocomposite nanofibrous mats

Despite the anticancer effect of lupeol (Lup), low aqueous solubility can make its therapeutic usage difficult. However, polycaprolactone/Gelatin (PCL-GEL) nanofibers scaffold eliminates this problem. This study has been conducted to recognize PCL-GEL-Lup nanofibers effect on cancer cell lines. PCL-GEL solution was prepared at different ratios (8 wt% and 4 wt%) for achieving optimal nanofibers. PCL-GEL-Lup nanofibers were provided via electrospinning technique. The surface morphology of nanofibers was examined using FESEM. Functional groups were investigated by a Fourier Transform Infrared spectroscopy. Lupeol released from nanofibers was detected by a UV-Visible spectroscopy. The drug release profile confirmed the sustained release of about 80% achieved within 40 h. IC₅₀of lupeol against ACHN and HSC-3 cell lines are 52.57 and 66.10μg ml^-1respectively. The study results from aid an understanding of the fabrication of a scaffold with an optimum dose of bioactive lupeol in 6 wt% with bead free uniform diameter that is capable of binding the drug efficiently. The enhanced cytotoxicity activity by effective diffusion and elution to the target achieved in this study help to develop a nanofiber in the ongoing battle against cancer.

Synthesis, characterization, and antimicrobial properties of novel dual drug loaded electrospun mat for wound dressing applications

Wound healing properties of some herbs have been known for decades. Recently, electrospun mats have been used as a wound dressing material due to the high surface area of fiber and ease of incorporation of drug into the fiber matrix. In this aspect, the incorporation of herbal extracts in electrospun matrix could provide synergistic effect for wound healing. In the present work, extracts from Cissus quadrangularis (CQ) and Galinsoga parviflora Cav (GP) were loaded into the PVA solution in different proportions. These solutions were used to produce nanofibrous mat in electrospinning and the characteristics of the mat were analyzed. The morphology of the fiber was analyzed using scanning electron microscope (SEM), the presence of functional groups was identified using Fourier transform infrared spectroscopy (FTIR). The result of drug release shows that the GP extract loaded PVA nanofibrous mat has sustained drug release of 28% after 8 h of incubation compared to CQ loaded PVA nanofibrous mat. This trend follows as the concentration of GP increases in the mixture. The antimicrobial efficiency of the prepared mat was evaluated against both Gram-negative bacteria E. coli and Gram-positive bacteria S. aureus. The prepared nanofibrous mat has shown excellent antibacterial activity, cell viability, hemocompatibility, and sufficient tensile properties which indicates that it could be a promising biomaterial for wound dressing application.