Solution blow spinning of highly deacetylated chitosan nanofiber scaffolds for dermal wound healing

Automatic in situ short-distance deposition of PLGA/PLLA composite nanofibrous membranes for personalized wound dressings

Improving the mechanical properties of wound dressings and achieving personalized automatic real-time in situ deposition are important for accelerating wound management and repair. In this study, we report a self-designed automatic in situ deposition device based on solution blow spinning (SBS) to prepare poly(lactic-co-glycolic acid) (PLGA) and poly-L-lactic acid (PLLA) composite (PLGA/PLLA) nanofibrous membranes for wound dressing at a short distance. Polymer solution and in situ deposition conditions, including air pressure, spinning distance, solvent extrusion rate, and spinning rate, were optimized using orthogonal experiments and characterized via dynamic mechanical analysis. The microscopic morphology and physical properties of the prepared PLGA/PLLA composite nanofibrous membranes show that their strength, adhesion, water vapor transmission rate (WVTR), water retention, water absorption, degradation, and other properties were sufficient for wound-dressing applications. To investigate the possibility of a biomedical wound-dressing material, tannic acid (TA) was incorporated into the PLGA/PLLA composite nanofibrous membranes. The resultant PLGA/PLLA/TA composite nanofibrous membranes exhibited good biocompatibility and exceptional antibacterial properties against both Escherichia coli and Staphylococcus aureus. A pilot animal study illustrated the potential of this in situ deposition of PLGA/PLLA/TA composite nanofibrous membranes across multiple applications in wound healing/repair by reducing wound scar tissue formation and fibroblast overactivation.

Evaluation of cytocompatibility and cell proliferation of electrospun chitosan/polyvinyl alcohol/montmorillonite clay scaffold with l929 cell lines in skin regeneration activity and in silico molecular docking studies

The present investigation describes the development of a novel Chitosan/Polyvinyl Alcohol/Montmorillonite Clay (CS/PVA/MMT) scaffold by adopting an electrospinning method, and their biocompatibility was evaluated in vitro with L929 fibroblast cell line to ascertain its use in wound healing applications. The fabricated scaffold was characterized using analytical techniques. FT-IR measurement exhibited the existence of relevant functional groups and XRD implies scaffolds' amorphous nature. The scaffold's morphology and pore diameter were assessed using TEM and SEM. The pore diameter of the as-prepared scaffold was approximately 125 nm. The antimicrobial assay of the scaffold was evaluated against selected pathogens which demonstrated higher antimicrobial efficacy. The scavenging activity tested using the DPPH assay showed remarkable scavenging capability. The wound healing properties were tested through the Cytotoxicity assay conducted on the L929 assay which proved the scaffold to be a suitable material for cell proliferation. Also, a Molecular docking investigation was carried out for CS/PVA/MMT ligand using human neutrophil elastase (HNE) 1H1B protein as a receptor in the CB-Dock server. Studies conducted in silico revealed strong interaction and high binding energy ratings of CS/PVA/MMT ligand with key residues of human neutrophil elastase (HNE) 1H1B proteins that help in tissue regeneration activity.

Tailorable mechanical and degradation properties of KCl-reticulated and BDDE-crosslinked PCL/chitosan/κ-carrageenan electrospun fibers for biomedical applications: Effect of the crosslinking-reticulation synergy

The development of intricated and interconnected porous mats is desired for many applications in biomedicine and other relevant fields. The mats that comprise the use of natural, bioactive, and biodegradable polymers are the focus of current research activities. In the present work, crosslinked fibers with improved characteristics were produced by incorporating 1,4-butanediol diglycidyl ether (BDDE) into a polymer formulation containing polycaprolactone (PCL), chitosan (CS), and κappa-carrageenan (κ-C). A slight variation of formic acid (FA)/acetic acid (AA) ratio used as a solvent system, significantly affected the characteristics of the produced fiber mats. Both polysaccharides and BDDE played a major role in tailoring mechanical properties when fibrous scaffolds were reticulated under KCl-mediated basic conditions for determined periods of time at 50 °C. In vitro biological assessment of the electrospun fiber mats revealed proliferation of MC3T3-E1 cells when incubated for 1 and 7 days. After staining the cells with 4',6-diamidino-2-phenylindole (DAPI)/rhodamine phalloidin an autofluorescence response was observed by fluorescence microscopy in the scaffold manufactured using a solvent with higher FA/AA ratio due to the formation of microfibers. The results demonstrated the potential of the BDDE-crosslinked PCL/CS/κ-C electrospun fibers as promising materials for biomedical applications that may include soft and bone tissue regeneration.

Advances in Biomedical Applications of Solution Blow Spinning

In recent years, Solution Blow Spinning (SBS) has emerged as a new technology for the production of polymeric, nanocomposite, and ceramic materials in the form of nano and microfibers, with similar features to those achieved by other procedures. The advantages of SBS over other spinning methods are the fast generation of fibers and the simplicity of the experimental setup that opens up the possibility of their on-site production. While producing a large number of nanofibers in a short time is a crucial factor in large-scale manufacturing, in situ generation, for example, in the form of sprayable, multifunctional dressings, capable of releasing embedded active agents on wounded tissue, or their use in operating rooms to prevent hemostasis during surgical interventions, open a wide range of possibilities. The interest in this spinning technology is evident from the growing number of patents issued and articles published over the last few years. Our focus in this review is on the biomedicine-oriented applications of SBS for the production of nanofibers based on the collection of the most relevant scientific papers published to date. Drug delivery, 3D culturing, regenerative medicine, and fabrication of biosensors are some of the areas in which SBS has been explored, most frequently at the proof-of-concept level. The promising results obtained demonstrate the potential of this technology in the biomedical and pharmaceutical fields.

Novel Scaffold Based on Chitosan Hydrogels/Phthalated Cashew Gum for Supporting Human Dental Pulp Stem Cells

Hydrogels are structures that have value for application in the area of tissue engineering because they mimic the extracellular matrix. Naturally obtained polysaccharides, such as chitosan (CH) and cashew gum, are materials with the ability to form polymeric networks due to their physicochemical properties. This research aimed to develop a scaffold based on chitosan and phthalated cashew tree gum and test it as a support for the growth of human mesenchymal stem cells. In this study, phthalation in cashew gum (PCG) was performed by using a solvent-free route. PCG-CH scaffold was developed by polyelectrolyte complexation, and its ability to support adherent stem cell growth was evaluated. The scaffold showed a high swelling rate. The pore sizes of the scaffold were analyzed by scanning electron microscopy. Human dental pulp stem cells (hDPSCs) were isolated, expanded, and characterized for their potential to differentiate into mesenchymal lineages and for their immunophenotypic profile. Isolated mesenchymal stem cells presented fibroblastoid morphology, plastic adhesion capacity, and differentiation in osteogenic, adipogenic, and chondrogenic lineages. Mesenchymal stem cells were cultured in scaffolds to assess cell adhesion and growth. The cells seeded on the scaffold showed typical morphology, attachment, and adequate distribution inside the matrix pores. Thus, cells seeded in the scaffold may improve the osteoinductive and osteoconductive properties of these biomaterials.

Fabrication of Bio-Based Film Comprising Metal Oxide Nanoparticles Loaded Chitosan for Wound Dressing Applications

In the current work, chitosan (CS)-metal oxide nanohybrid (MONH) composites are prepared via combining CS with MONH made of vanadium oxide (V₂O₅), ytterbium trioxide (Yb₂O₃), and graphene oxide (GO) to generate promising wound dressing materials using the film-casting method. The developed nanohybrid@CS was examined using techniques such as Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX), and thermogravimetric analysis (TGA). For Yb₂O₃@CS, the surface morphology was shown to be a rough and porous surface with pores that ranged in size from 3.0 to 5.0 µm. For CS with Yb₂O₃, Yb₂O₃/V₂O₅@CS, and Yb₂O₃/V₂O₅/GO@CS, the contact angles were 72.5°, 68.2°, and 46.5°, respectively. When the nanohybrid@CS was in its hydrophilic phase, which is good for absorbing moisture and drugs, there was a notable decrease in angles that tended to rise. Additionally, the inclusion of MONH allowed the cell viability to be confirmed with an IC₅₀ of 1997.2 g/mL and the cell growth to reach 111.3% at a concentration of 7.9 g/mL.