Coaxial electrospinning of composite mats comprised of core/shell poly(methyl methacrylate)/silk fibroin fibers for tissue engineering applications

A Review on Advances and Challenges in Core-Shell Scaffolds for Bone Tissue Engineering: Design, Fabrication, and Clinical Translation

This review explores core-shell scaffolds in bone tissue engineering, highlighting their osteoconductive and osteoinductive properties critical for bone growth and regeneration. Key design factors include material selection, porosity, mechanical strength, biodegradation kinetics, and bioactivity. Electrospun core-shell nanofibrous scaffolds demonstrate potential in delivering therapeutic agents and enhancing bone regeneration. Critical characterization techniques include structural, surface, chemical composition, mechanical, and degradation analyses. Scaling up production poses challenges, addressed by innovative electrospinning techniques. Future research focuses on regulatory and commercial considerations, while exploring advanced materials and fabrication methods to optimize scaffold performance for improved clinical outcomes.

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.

Improvement of Osteogenic Differentiation of Mouse Pre-Osteoblastic MC3T3-E1 Cells on Core-Shell Polylactic Acid/Chitosan Electrospun Scaffolds for Bone Defect Repair

Electrospun hybrid scaffolds composed of synthetic and natural polymers have gained increasing interest in tissue engineering applications over the last decade. In this work, scaffolds composed of polylactic acid electrospun fibers, either treated (P-PLA) or non-treated (PLA) with air-plasma, were coated with high molecular weight chitosan to create a core-shell microfibrous structure. The effective thickness control of the chitosan layer was confirmed by gravimetric, spectroscopic (FTIR-ATR) and morphological (SEM) investigations. The chitosan coating increased the fiber diameter of the microfibrous scaffolds while the tensile mechanical tests, conducted in dry and wet environments, showed a reinforcing action of the coating layer on the scaffolds, in particular when deposited on P-PLA samples. The stability of the Chi coating on both PLA and P-PLA substrates was confirmed by gravimetric analysis, while their mineralization capacity was evaluated though scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) after immersing the scaffolds in simulated body fluids (SBF) at 37 °C for 1 week. Sample biocompatibility was investigated through cell viability assay and SEM analysis on mouse pre-osteoblastic MC3T3-E1 cells grown on scaffolds at different times (1, 7, 14 and 21 days). Finally, Alizarin Red assay and qPCR analysis suggested that the combination of plasma treatment and chitosan coating on PLA electrospun scaffolds influences the osteoblastic differentiation of MC3T3-E1 cells, thus demonstrating the great potential of P-PLA/chitosan hybrid scaffolds for bone tissue engineering applications.

Progress in advanced electrospun membranes for CO2 capture: Feedstock, design, and trend

The emission of large amounts of carbon dioxide has caused serious environmental problems and hindered the construction of a green and low-carbon society. Efficient carbon dioxide capture has become an important means to slow down global climate warming and achieve effective utilization of carbon dioxide. Membranes synthesized by electrospinning technology are becoming promising carbon capture materials due to their unique characteristics. This review describes the features of membranes prepared from available raw materials and presents their application performances in carbon capture. The preparation methods of various types of membrane materials with excellent capture performance are summarized, and the effects of electrospinning parameters on electrospun fibers are systematically analyzed. Furthermore, recommendations and expectations for further development of electrospun membranes for carbon capture applications are given. These works provide important references for an in-depth understanding of the development status of electrospun membranes in the field of carbon capture and for expanding future research.

Electrospun nanofibers applications in caries lesions: prevention, treatment and regeneration

Dental caries is a multifactorial disease primarily mediated by biofilm formation, resulting in a net loss of mineral content and degradation of organic matrix in dental hard tissues. Caries lesions of varying depths can result in demineralization of the superficial enamel, the formation of deep cavities extending into the dentin, and even pulp infection. Electrospun nanofibers (ESNs) exhibit an expansive specific surface area and a porous structure, closely mimicking the unique architecture of the natural extracellular matrix (ECM). This unique topography caters to the transport of small molecules and facilitates localized therapeutic drug delivery, offering great potential in regulating cell behavior, and thereby attracting interest in ESNs' applications in the treatment of caries lesions and the reconditioning of the affected dental tissues. Thus, this review aims to consolidate the recent developments in ESNs' applications for caries lesions. This review begins with an introduction to the electrospinning technique and provides a comprehensive overview of the biological properties and modification methods of ESNs, followed by an introduction outlining the basic pathological processes, classification and treatment requirements of caries lesions. Finally, the review offers a detailed examination of the research progress on the ESNs' application in caries lesions and concludes by addressing the limitations.

Silk fibroin-derived electrospun materials for biomedical applications: A review

Electrospinning is a versatile technique for fabricating polymeric fibers with diameters ranging from micro- to nanoscale, exhibiting multiple morphologies and arrangements. By combining silk fibroin (SF) with synthetic and/or natural polymers, electrospun materials with outstanding biological, chemical, electrical, physical, mechanical, and optical properties can be achieved, fulfilling the evolving biomedical demands. This review highlights the remarkable versatility of SF-derived electrospun materials, specifically focusing on their application in tissue regeneration (including cartilage, cornea, nerves, blood vessels, bones, and skin), disease treatment (such as cancer and diabetes), and the development of controlled drug delivery systems. Additionally, we explore the potential future trends in utilizing these nanofibrous materials for creating intelligent biomaterials, incorporating biosensors and wearable sensors for monitoring human health, and also discuss the bottlenecks for its widespread use. This comprehensive overview illuminates the significant impact and exciting prospects of SF-derived electrospun materials in advancing biomedical research and applications.

Three-Dimensional Bioprinting of Biocompatible Photosensitive Polymers for Tissue Engineering Application

Three-dimensional (3D) bioprinting, or additive manufacturing, is a rapid fabrication technique with the foremost objective of creating biomimetic tissue and organ replacements in hopes of restoring normal tissue function and structure. Generating the engineered organs with an infrastructure that is similar to that of the real organs can be beneficial to simulate the functional organs that work inside our bodies. Photopolymerization-based 3D bioprinting, or photocuring, has emerged as a promising method in engineering biomimetic tissues due to its simplicity, and noninvasive and spatially controllable approach. In this review, we investigated types of 3D printers, mainstream materials, photoinitiators, phototoxicity, and selected tissue engineering applications of 3D photopolymerization bioprinting.

Advances in antimicrobial hydrogels for dental tissue engineering: regenerative strategies for endodontics and periodontics

Dental tissue infections have been affecting millions of patients globally leading to pain, severe tissue damage, or even tooth loss. Commercial sterilizers may not be adequate to prevent frequent dental infections. Antimicrobial hydrogels have been introduced as an effective therapeutic strategy for endodontics and periodontics since they have the capability of imitating the native extracellular matrix of soft tissues. Hydrogel networks are considered excellent drug delivery platforms due to their high-water retention capacity. In this regard, drugs or nanoparticles can be incorporated into the hydrogels to endow antimicrobial properties as well as to improve their regenerative potential, once biocompatibility criteria are met avoiding high dosages. Herein, novel antimicrobial hydrogel formulations were discussed for the first time in the scope of endodontics and periodontics. Such hydrogels seem outstanding candidates especially when designed not only as simple volume fillers but also as smart biomaterials with condition-specific adaptability within the dynamic microenvironment of the defect site. Multifunctional hydrogels play a pivotal role against infections, inflammation, oxidative stress, etc. along the way of dental regeneration. Modern techniques (e.g., 3D and 4D-printing) hold promise to develop the next generation of antimicrobial hydrogels together with their limitations such as infeasibility of implantation.

Antimicrobial Activities of Polyethylene Terephthalate-Waste-Derived Nanofibrous Membranes Decorated with Green Synthesized Ag Nanoparticles

Thermoplastic polymers are one of the synthetic materials produced with high tonnage in the world and are so omnipresent in industries and everyday life. One of the most important polymeric wastes is polyethylene terephthalate (PET), and the disposal of used PET bottles is an unsolved environmental problem, and many efforts have been made to find practical solutions to solve it. In this present work, nanofibrous membranes were produced from waste PET bottles using the electrospinning process. The surface of membranes was modified using NaOH and then decorated with green synthesized Ag nanoparticles (10 ± 2 nm) using an in situ chemical reduction method. The morphology, size, and diameter of the Ag nanoparticles decorating the nanofibers were characterized through transmission electron microscopy (TEM), a field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV-visible spectroscopy techniques. Finally, the antimicrobial activity of the nanofibrous membranes was tested against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus using disc diffusion and colony-forming count methods. The growth of bacteria was not affected by the pure nanofibrous membranes, while the Ag-decorated samples showed inhibition zones of 17 ± 1, 16 ± 1, and 14 ± 1 mm for Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus, respectively. The planktonic culture results of Pseudomonas aeruginosa showed that the membranes had a relatively low inhibitory effect on its growth. The obtained results showed that Pseudomonas aeruginosa has a relatively low ability to form biofilms on the nanostructured membranes too. A good agreement was observed between the data of biofilm formation and the planktonic cultures of bacteria. The plastic-waste-derived PET/Ag nanocomposite membranes can be used for wound dressings, air filters, and water purification applications.

Combining Polymer and Cyclodextrin Strategy for Drug Release of Sulfadiazine from Electrospun Fibers

This study reports the fabrication of polymeric matrices through electrospinning using polymethyl methacrylate (PMMA) and poly(lactic-co-glycolic acid) (PLGA), biocompatible polymers commonly used in medical systems. These polymers were combined with an antibacterial drug, sulfadiazine sodium salt (SDS) or its supramolecular system formed with hydroxypropyl-β-cyclodextrin (HPβ/CD) at 1:1 molar ratio, aiming to assemble a transdermal drug delivery system. The formation of fibers was confirmed by scanning electron microscopy (SEM), and the fibers' surface properties were analyzed using contact angle and water vapor permeability techniques. Drug release tests and cell viability assays were performed to evaluate the potential toxicity of the material. SEM images demonstrated that the obtained fibers had nanoscale- and micrometer-scale diameters in PLGA and PMMA systems, respectively. The contact angle analyses indicated that, even in the presence of hydrophilic molecules (SDS and HPβCD), PMMA fibers exhibited hydrophobic characteristics, while PLGA fibers exhibited hydrophilic surface properties. These data were also confirmed by water vapor permeability analysis. The drug release profiles demonstrated a greater release of SDS in the PLGA system. Moreover, the presence of HPβCD improved the drug release in both polymeric systems and the cell viability in the PMMA SDS/HPβCD system. In terms of antibacterial activity, all membranes yielded positive outcomes; nevertheless, the PLGA SDS/HPβCD membrane exhibited the most remarkable results, with the lowest microbial load values. Additionally, the pseudo wound healing analysis demonstrated that the PLGA SDS/HPβCD fiber exhibited results similar to the control group. Consequently, these findings exemplify the substantial potential of the obtained materials for use in wound healing applications.

Injectable methacrylated gelatin/thiolated pectin hydrogels carrying melatonin/tideglusib-loaded core/shell PMMA/silk fibroin electrospun fibers for vital pulp regeneration

Use of injectable hydrogels attract attention in the regeneration of dental pulp due to their ability to fill non-uniform voids such as pulp cavities. Here, gelatin methacrylate/thiolated pectin hydrogels (GelMA/PecTH) carrying electrospun core/shell fibers of melatonin (Mel)-polymethylmethacrylate (PMMA)/Tideglusib (Td)-silk fibroin (SF) were designed as an injectable hydrogel for vital pulp regeneration, through prolonged release of Td and Mel to induce proliferation and odontoblastic differentiation of dental pulp stem cells (DPSC). H NMR and FTIR confirmed methacrylation of Gel and thiolation of Pec. Addition of PMMA/SF increased degradation and water retention capacities of GelMA/PecTH. Rheological analyses and syringe tests proved the injectability of the hydrogel systems. Release studies indicated that Td and Mel were released from the fibers inside the hydrogels sequentially due to their specific locations. This release pattern from the hydrogels resulted in DPSC proliferation and odontogenic differentiation in vitro. Gene expression studies showed that the upregulation of DMP1, DSPP, and Axin-2 genes was promoted by GelMA/PecTH carrying PMMA/SF loaded with Mel (50 µg/mL) and Td (200 nM), respectively. Our results suggest that this hydrogel system holds promise for use in the regeneration of pulp tissue.

A Molecular View on Biomaterials and Dental Stem Cells Interactions: Literature Review

Biomaterials and stem cells are essential components in the field of regenerative medicine. Various biomaterials have been designed that have appropriate biochemical and biophysical characteristics to mimic the microenvironment of an extracellular matrix. Dental stem cells (DT-MSCs) represent a novel source for the development of autologous therapies due to their easy availability. Although research on biomaterials and DT-MSCs has progressed, there are still challenges in the characteristics of biomaterials and the molecular mechanisms involved in regulating the behavior of DT-MSCs. In this review, the characteristics of biomaterials are summarized, and their classification according to their source, bioactivity, and different biological effects on the expansion and differentiation of DT-MSCs is summarized. Finally, advances in research on the interaction of biomaterials and the molecular components involved (mechanosensors and mechanotransduction) in DT-MSCs during their proliferation and differentiation are analyzed. Understanding the molecular dynamics of DT-MSCs and biomaterials can contribute to research in regenerative medicine and the development of autologous stem cell therapies.

Preparation of Needleless Electrospinning Polyvinyl Alcohol/Water-Soluble Chitosan Nanofibrous Membranes: Antibacterial Property and Filter Efficiency

Electrospinning is an efficient method of producing nanofibers out of polymers that shows a great potential for the filtration territory. Featuring water-soluble chitosan (WS-CS), a low-pollution process and a self-made needleless machine, PVA/WS-CS nanofibrous membranes were prepared and evaluated for nanofiber diameter, bacteriostatic property, filtration efficiency, pressure drop, and quality factor. Test results indicate that the minimal fiber diameter was 216.58 ± 58.15 nm. Regardless of the WS-CS concentration, all of the PVA/WS-CS nanofibrous membranes attained a high porosity and a high water vapor transmission rate (WVTR), with a pore size of 12.06–22.48 nm. Moreover, the membranes also exhibit bacteriostatic efficacy against Staphylococcus aureus, an optimal quality factor of 0.0825 Pa⁻¹, and a filtration efficiency as high as 97.0%, that is 72.5% higher than that of common masks.

Novel Trends into the Development of Natural Hydroxyapatite-Based Polymeric Composites for Bone Tissue Engineering

In recent years, the number of people needing bone replacements for the treatment of defects caused by chronic diseases or accidents has continuously increased. To solve these problems, tissue engineering has gained significant attention in the biomedical field, by focusing on the development of suitable materials that improve osseointegration and biologic activity. In this direction, the development of an ideal material that provides good osseointegration, increased antimicrobial activity and preserves good mechanical properties has been the main challenge. Currently, bone tissue engineering focuses on the development of materials with tailorable properties, by combining polymers and ceramics to meet the necessary complex requirements. This study presents the main polymers applied in tissue engineering, considering their advantages and drawbacks. Considering the potential disadvantages of polymers, improving the applicability of the material and the combination with a ceramic material is the optimum pathway to increase the mechanical stability and mineralization process. Thus, ceramic materials obtained from natural sources (e.g., hydroxyapatite) are preferred to improve bioactivity, due to their similarity to the native hydroxyapatite found in the composition of human bone.