Evaluation of the factors influencing the resultant diameter of the electrospun gelatin/sodium alginate nanofibers via Box–Behnken design

Electrospinning and electrospun polysaccharide-based nanofiber membranes: A review

The electrospinning technology has set off a tide and given rise to the attention of a widespread range of research territories, benefiting from the enhancement of nanofibers which made a spurt of progress. Nanofibers, continuously produced via electrospinning technology, have greater specific surface area and higher porosity and play a non-substitutable key role in many fields. Combined with the degradability and compatibility of the natural structure characteristics of polysaccharides, electrospun polysaccharide nanofiber membranes gradually infiltrate into the life field to help filter air contamination particles and water pollutants, treat wounds, keep food fresh, monitor electronic equipment, etc., thus improving the life quality. Compared with the evaluation of polysaccharide-based nanofiber membranes in a specific field, this paper comprehensively summarized the existing electrospinning technology and focused on the latest research progress about the application of polysaccharide-based nanofiber in different fields, represented by starch, chitosan, and cellulose. Finally, the benefits and defects of electrospun are discussed in brief, and the prospects for broadening the application of polysaccharide nanofiber membranes are presented for the glorious expectation dedicated to the progress of the eras.

Development of Verapamil Hydrochloride-loaded Biopolymer-based Composite Electrospun Nanofibrous Mats: In vivo Evaluation of Enhanced Burn Wound Healing without Scar Formation

Introduction

Researchers aim for new heights in wound healing to produce wound dressings with unique features. Natural, synthetic, biodegradable, and biocompatible polymers especially in the nanoscale are being employed to support and provide efficient wound management. Economical and environmentally friendly sustainable wound management alternatives are becoming an urgent issue to meet future needs. Nanofibrous mats possess unique properties for ideal wound healing. They mimic the physical structure of the natural extracellular matrix (ECM), promote hemostasis, and gas permeation. Their interconnected nanoporosity prevents wound dehydration and microbial infiltration.

Purpose

To prepare and evaluate a novel verapamil HCl-loaded environmentally friendly composite, with biopolymer-based electrospun nanofibers suitable for application as wound dressings providing adequate wound healing with no scar formation.

Methods

Composite nanofibers were prepared by electrospinning of a blend of the natural biocompatible polymers, sodium alginate (SA) or zein (Z) together with polyvinyl alcohol (PVA). Composite nanofibers were characterized in terms of morphology, diameter, drug entrapment efficiency, and release. In vivo study of the therapeutic efficacy of verapamil HCl-loaded nanofibers on a Sprague Dawley rat model with dermal burn wound was investigated in terms of percent wound closure, and presence of scars.

Results

Combining PVA with SA or Z improved the electrospinnability and properties of the developed nanofibers. Verapamil HCl-loaded composite nanofibers showed good pharmaceutical attributes favorable for wound healing including, fiber diameter ∼150 nm, high entrapment efficiency (∼80-100%) and biphasic controlled drug release for 24 h. In vivo study demonstrated promising potentials for wound healing without scaring.

Conclusion

The developed nanofibrous mats combined the beneficial properties of the biopolymers and verapamil HCl to provide an increased functionality by exploiting the unique advantages of nanofibers in wound healing at a small dose proved to be insufficient in case of the conventional dosage form.

Fabrication and characterization of electrospun biopolyester/gelatin nanofibers

Poly(ω-pentadecalactone-co-ε-caprolactone) copolymer (PDL-CL) is an enzymatically synthesized aliphatic biopolyester, which has been participated in a nanofibrous structure for the first time. Electrospinning of this synthetic polymer by blending with a natural polymer such as gelatin (Gel) could provide new characteristics that are significant for biomedical applications, such as drug delivery, wound healing, and tissue engineering. In the present study, PDL-CL/Gel nanofibrous membranes were successfully produced and characterized. The average diameter of nanofibers was 305.0 ± 45.5 nm that may be beneficial in applications mentioned above. In order to increase hydrolytic resistance, cross-linking with glutaraldehyde vapor was applied. Cross-linking for 2 h was enough to obtain a nanofibrous membrane that was able to resist in pH 7.4 phosphate buffered saline for 30 days. In addition, contact angle measurement results had shown that, cross-linked nanofibrous membrane had good wettability, which is a required specification to be applied in biomedical field. Hence, this study provides an overview on fabrication of fine PDL-CL/Gel nanofibers, which may have potential to be used in biomedical area.

Electrospun pectin/modified copper-based metal-organic framework (MOF) nanofibers as a drug delivery system

Pectin has been regarded as a drug carrier accelerating the healing process due to its bioactivities, abundance and lower cost of resources. However, a big challenge related to its practical application is its poor mechanical strength. In this study the modified Cu-based MOF containing Folic acid was synthesized and incorporated in the suitable pectin electrospun nanofibers which not only improved the copper ions release behavior but also made the fiber mat stronger, antibacterial and induce angiogenesis, fibroblast migration, and proliferation due to loaded copper ions and folic acid. The nanofibers composing of 75% pectin and 4000 kDa -PEO were chosen after morphological and mechanical characterization. Finally, the effect of MOF incorporation on the nanocomposite samples was characterized in terms of morphological, physiochemical and biological properties. The nanofibrous mats were evaluated by tensile testing, antibacterial and cytotoxicity. The release behavior of copper ions and folic acid was controlled and their burst release alleviated reducing cytotoxicity in vitro. It was found that the Young's moduli of the pectin nanofibers were improved to 19.13 MPa by the addition of Cu-based MOFs. Moreover, nanocomposite pectin nanofibers were found to be antibacterial and biocompatible. These results demonstrate that MOF-contained pectin nanofibers are promising for biomedical applications.

Electrospun Alginate Nanofibers Toward Various Applications: A Review

Alginate has been a material of choice for a spectrum of applications, ranging from metal adsorption to wound dressing. Electrospinning has added a new dimension to polymeric materials, including alginate, which can be processed to their nanosize levels in order to afford unique nanostructured materials with fascinating properties. The resulting nanostructured materials often feature high porosity, stability, permeability, and a large surface-to-volume ratio. In the present review, recent trends on electrospun alginate nanofibers from over the past 10 years toward advanced applications are discussed. The application of electrospun alginate nanofibers in various fields such as bioremediation, scaffolds for skin tissue engineering, drug delivery, and sensors are also elucidated.

Wet electrospun alginate/gelatin hydrogel nanofibers for 3D cell culture

Convergence of biological and biofabrication approaches is necessary to progress new biomaterials promoting three-dimensional (3D) cell growth and maturation towards tissue regeneration and integration. Here, we have developed a novel approach to fabricate 3D macroporous, alginate/gelatin hydrogel nanofibers (Alg/GelF-MA), which provide superior cell adhesion, motility, proliferation and maturation. The electrospinning process greatly depends on the ionic strength and viscoelastic behavior of the solution. The polyelectrolyte nature of alginate favors intramolecular bundles over intermolecular entanglement, which hinders its electrospinnability. Electrospinning of alginate was achieved by the aid of a supporting polymer, polyethylene oxide and a surfactant, Pluronic®F127. Furthermore, the Ca²⁺-mediated coagulation process of alginate was realized in situ during wet electrospinning, where the rapid physical crosslink-ability of alginate was applied in conjunction with the jet entrance into the wet electrospinning collector, a coagulation bath. Consequently, the rapid formation of Ca²⁺-alginate complex stabilized the nanofiber morphology. The low surface tension of the non-solvent ethanol used in the bath prevented fibers from dense packing, thus allowing the generation of 3D macroporous structure favoring cell motility. The subsequent UV-mediated chemical crosslinking further stabilized the gelatin content in the Alg/GelF-MA hydrogel nanofibers. It is demonstrated that the Alg/GelF-MA nanofibers with low cytotoxicity (below 10%) supported an over 8-fold proliferation of mesenchymal stem cells over 5 weeks and supported the maturation of human iPSC-derived ventricular cardiomyocytes, which significantly outperform the cell encapsulated bulk GelF-MA hydrogel. The work provides an insight for rational design and development of 3D cell culture matrix for advancement of stem cell therapy and tissue regeneration.

Application of response surface methodology to tailor the surface chemistry of electrospun chitosan-poly(ethylene oxide) fibers

Chitosan is a promising biocompatible polymer for regenerative engineering applications, but its processing remains challenging due to limited solubility and rigid crystalline structure. This work represents the development of electrospun chitosan/poly(ethylene oxide) blend nanofibrous membranes by means of a numerical analysis in order to identify and tailor the main influencing parameters with respect to accessible surface nitrogen functionalities which are of importance for the biological activity as well as for further functionalization. Depending on the solution composition, both gradient fibers and homogenous blended fiber structures could be obtained with surface nitrogen concentrations varying between 0 and 6.4%. Response surface methodology (RSM) revealed chitosan/poly(ethylene oxide) ratio and chitosan molecular weight as the main influencing factors with respect to accessible nitrogen surface atoms and respective concentrations. The model showed good adequacy hence providing a tool to tailor the surface properties of chitosan/poly(ethylene oxide) blends by addressing the amount of accessible chitosan.