Electrospun Nanofibers For Tissue Engineering Research Articles

Nanoclay-Doped Electrospun Nanofibers for Tissue Engineering: Investigation on the Structural Modifications in Physiological Environment.

Clay minerals are nanomaterials that have recently been recognized as enabling excipients that can promote cell adhesion, proliferation, and differentiation. When nanoclays are loaded in a 3D polymeric nanostructure, the cell-substrate interaction is enhanced, and other bioactive properties are optimized. In this study, hectorite (HEC)- and montmorillonite (MMT)-doped polymeric scaffolds were explored for the treatment of deep and chronic skin lesions. Scaffolds were manufactured by means of electrospinning and then crosslinked by heating. Physicochemical analyses were correlated with in vitro biopharmaceutical characterization to predict the in vivo fate of the clay-doped scaffolds. The addition of MMT or HEC to the polymeric scaffold framework modifies the surface arrangement and, consequently, the potential of the scaffolds to interact with biological proteins. The presence of nanoclays alters the nanofiber morphology and size, and MMT doping increases wettability and protein adhesion. This has an impact on fibroblast behavior in a shorter time since scaffold stiffness facilitates cell adhesion and cell proliferation. MMT proved to perform better than HEC, and this could be related to its higher hydrophilicity and protein adhesion.

Production of fungal chitosan and fabrication of fungal chitosan/polycaprolactone electrospun nanofibers for tissue engineering.

The present study investigated that chitosan production of Rhizopus oryzae NRRL 1526 and Aspergillus niger ATCC 16404. Fungal chitosans were characterized by scanning electron microscopy (SEM)-energy dispersive X-ray analysis, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter and deacetylation degrees of fungal chitosans were determined. The percentage yield of Ro-chitosan and An-chitosan were determined as 18.6% and 12.5%, respectively. According to percentage of chitosan yield and the results of the characterization studies, chitosan that obtained from Rhizopus oryzae NRRL 1526 was selected for subsequent studies. Cytotoxicity of chitosan obtained from Rhizopus oryzae NRRL 1526 was determined by MTT assay on human dermal fibroblast cell line. Acording to results of the cytotoxicity test fungal chitosan was nontoxic on cells. The high cell viability was observed 375 μg/mL concentration at 24th, 48th h periods and at the 187.5μg/ml 72nd h periods on cells. The fungal chitosan obtained from Rhizopus oryzae NRRL 1526 was used to fabrication of electrospun nanofibers. Fungal chitosan based polymer solutions were prepared by adding different substances and different electrostatic spinning parameters were used to obtain most suitable nanofiber structure. Characterization studies of nanofibers were carried out by SEM, FTIR and X-ray diffraction. The most suitable nanofiber structure was determined as F4 formula. The nanofiber structure was evaluated to be thin, bead-free, uniform, flexible and easily remove from surface and taking the shape of the area. After the characterization analysis of fungal chitosan it was determined that the chitosan, which obtained from Rhizopus oryzae NRRL 1526 is actually chitosan polymer and this polymer is usable for pharmaceutical areas and biotechnological applications. The electrospun nanofiber that blends fungal chitosan and PCL polymers were fabricated successfully and that it can be used as fabrication wound dressing models. RESEARCH HIGHLIGHTS: Extraction of chitosan from Rhizopus oryzae NRRL 1526 and Aspergillus niger ATCC 16404 and characterization scanning electron microscopy-energy dispersive X-ray analysis, Fourier transform infrared spectroscopy, differential scanning calorimeter. Fabrication and characterization of the fungal chitosan/PCL electrospun nanofibers.

Electrospun Nanofibers for Tissue Engineering: Desired Properties

Electrospun nanofibers have gained great attention in the biomedical industry, especially in tissue engineering, because of their interesting properties that promote cell growth and tissue cicatrization or regeneration, where any biological tissue can be beneficiated by choosing the proper biomaterials. Hence, the objective of this perspective article is to give an insight into the desired properties of the electrospun nanofibers dedicated to the tissue engineering approach. A high tensile strength, flexibility, reduced permeability of water, high surface area, biocompatibility, and biodegradability are some of the properties recognized and discussed to be more important for tissue engineering applications. The purpose of these properties is to mimic the surrounding tissue or create the optimal condition for the targeted cell growth. Despite all the reported literature, it still is missing a complete screening of the above mentioned properties specific to their respective target tissues.

High efficiency biomimetic electrospun fibers for use in regenerative medicine and drug delivery: A review

Regenerative medicine is a very promising field for the reconstruction of diseased or defective tissues. Biocompatible materials play an important role in making the synthetic extracellular matrix (ECM) environments as three-dimensional (3D) scaffolds for tissue regeneration. These scaffolds should be able to imitate some aspects of the extracellular matrix. Therefore, electrospun-based fibers that can mimic the main elements of the natural matrix are an inspired strategy for restoring tissue response. Nanofibers are effectively helpful for various medical, tissue engineering, and drug delivery applications due to their high surface area. In this regard, to achieve greater efficiency of nanofibers, their surface is functionalized with different strategies to continuously release various factors in drug delivery and increase cellular response in tissue engineering. This paper contains a comprehensive overview of the application of biomimetic electrospun nanofibers in tissue engineering and drug delivery. The article also focuses on the production, benefits, and applications of various biomimetic fibers that can be used in tissue engineering and drug delivery. In addition, the different techniques used to modify the surface of nanofibers in tissue engineering and drug delivery are briefly discussed.

Electroactive electrospun nanofibers for tissue engineering

The ability of electrospun nanofibers to mimic the structure and composition of certain components of the extracellular matrix (ECM) has been widely used in the construction of tissue regeneration scaffolds. As the biophysical cues of the ECM, bioelectric communication mediated by endogenous electrical fields and currents also plays an important role in the repair and regeneration of defected tissues. To this end, it is compelling to develop electroactive electrospun nanofibers for tissue engineering. Here, we briefly summarize the commonly developed electroactive electrospun nanofibers and their progress in tissue engineering, especially for heart repair, nerve injury treatment, wound healing, skeletal muscle and bone regeneration. We also discuss their potential applications as biosensors and drug delivery platforms. Afterwards, we specifically focus on the future direction of the design and functionalization of electroactive electrospun nanofibers for tissue engineering. At last, we propose several promising strategies to make the scaffolds more intelligent, portable, monitorable, and safe.

Applications of Electrospinning for Tissue Engineering in Otolaryngology.

In tissue engineering, biomaterials create a 3D scaffold for cell-to-cell adhesion, proliferation and tissue formation. Because of their similarity to extracellular matrix and architectural adaptability, nanofibers are of particular interest in tissue engineering. Electrospinning is a well-documented technique for nanofiber production for tissue engineering scaffolds. Here we present literature on the applications of electrospinning in the field of otolaryngology. A PubMed database search was performed to isolate articles published about applications of electrospun nanofibers for tissue engineering in otolaryngology. Study design, size, material tested, site of application within the head and neck, and outcomes were obtained for each study. Almost all data on electrospinning in otolaryngology was published in the last 6 years (84%), highlighting its novelty. A total of 25 pre-clinical studies were identified: 9 in vitro studies, 5 in vivo animal studies, and 11 combination studies. Sites of application included: tracheal reconstruction (n = 16), tympanic membrane repair (n = 3), cranial nerve regeneration (n = 3), mastoid osteogenesis (n = 1) and ear/nose chondrogenesis (n = 2). Tissue engineering is a burgeoning field, with recent innovative applications in the field of otolaryngology. Electrospun nanofibers specifically have relevant applications in the field of otolaryngology, due in part to their similarity to native extracellular matrix, with emerging areas of interest being tympanic membrane repair, cranial nerve regeneration and tracheal reconstruction.

Resorbable polymer electrospun nanofibers: History, shapes and application for tissue engineering

Resorbable polymer electrospun nanofiber-based materials/devices have high surface-to-volume ratio and often have a porous structure with excellent pore interconnectivity, which are suitable for growth and development of different types of cells. Due to the huge advantages of both resorbable polymers and electrospun nanofibers, resorbable polymer electrospun nanofibers (RPENs) have been widely applied in the field of tissue engineering. In this paper, we will mainly introduce RPENs for tissue engineering. Firstly, the electrospinning technique and electrospun nanofiber architectures are briefly introduced. Secondly, the application of RPENs in the field of tissue engineering is mainly reviewed. Finally, the advantages and disadvantages of RPENs for tissue engineering are discussed. This review will provide a comprehensive guide to apply resorbable polymer electrospun nanofibers for tissue engineering.

Electrospun Nanofibers for Tissue Engineering with Drug Loading and Release.

Electrospinning technologies have been applied in the field of tissue engineering as materials, with nanoscale-structures and high porosity, can be easily prepared via this method to bio-mimic the natural extracellular matrix (ECM). Tissue engineering aims to fabricate functional biomaterials for the repairment and regeneration of defective tissue. In addition to the structural simulation for accelerating the repair process and achieving a high-quality regeneration, the combination of biomaterials and bioactive molecules is required for an ideal tissue-engineering scaffold. Due to the diversity in materials and method selection for electrospinning, a great flexibility in drug delivery systems can be achieved. Various drugs including antibiotic agents, vitamins, peptides, and proteins can be incorporated into electrospun scaffolds using different electrospinning techniques and drug-loading methods. This is a review of recent research on electrospun nanofibrous scaffolds for tissue-engineering applications, the development of preparation methods, and the delivery of various bioactive molecules. These studies are based on the fabrication of electrospun biomaterials for the repair of blood vessels, nerve tissues, cartilage, bone defects, and the treatment of aneurysms and skin wounds, as well as their applications related to oral mucosa and dental fields. In these studies, due to the optimal selection of drugs and loading methods based on electrospinning, in vitro and in vivo experiments demonstrated that these scaffolds exhibited desirable effects for the repair and treatment of damaged tissue and, thus, have excellent potential for clinical application.

Electrospun PCL/GO-g-PEG structures: Processing-morphology-properties relationships

Polycaprolactone (PCL) biocomposite nanofiber scaffolds with different concentrations of graphene oxide (GO) and GO surface grafted with poly(ethylene glycol) (GO-g-PEG) were prepared by electrospinning. Morphological, mechanical as well as wettability characterizations of electrospun nanofibers were carried out. Results showed that the average diameter of PLA/GO electrospun nanofibers decreased upon increasing the filler content. Differently, the diameter increased while using GO-g-PEG. Both nanofillers enhanced the electrospun PCL hydrophilicity even if PCL/GO-g-PEG samples exhibited improved wettability. The Young moduli of the composite nanofiber mats were improved by adding GO, and it was further enhanced when GO was surface grafted with PEG, in particular at low concentrations. This suggests the improved dispersion of GO-g-PEG due to the surface grafting with PEG. Furthermore, in order to assess the potential applications of the electrospun nanofibers in tissue engineering, MC3T3-E1 cells were cultured on PCL and PCL/GO-g-PEG scaffolds, thus providing preliminary and comparative proliferation rate assays.

Ozone Gas as a Benign Sterilization Treatment for PLGA Nanofiber Scaffolds.

The use of electrospun nanofibers for tissue engineering and regenerative medicine applications is a growing trend as they provide improved support for cell proliferation and survival due, in part, to their morphology mimicking that of the extracellular matrix. Sterilization is a critical step in the fabrication process of implantable biomaterial scaffolds for clinical use, but many of the existing methods used to date can negatively affect scaffold properties and performance. Poly(lactic-co-glycolic acid) (PLGA) has been widely used as a biodegradable polymer for 3D scaffolds and can be significantly affected by current sterilization techniques. The aim of this study was to investigate pulsed ozone gas as an alternative method for sterilizing PLGA nanofibers. The morphology, mechanical properties, physicochemical properties, and response of cells to PLGA nanofiber scaffolds were assessed following different degrees of ozone gas sterilization. This treatment killed Geobacillus stearothermophilus spores, the most common biological indicator used for validation of sterilization processes. In addition, the method preserved all of the characteristics of nonsterilized PLGA nanofibers at all degrees of sterilization tested. These findings suggest that ozone gas can be applied as an alternative method for sterilizing electrospun PLGA nanofiber scaffolds without detrimental effects.

3D scaffold prepared by electrospun nanofibers for tissue engineering

3D scaffold prepared by electrospun nanofibers for tissue engineering

Fabrication and Characterization of PCL/GE-Based Electrospun Nanofibers for Tissue Engineering and Drug Delivery Application

Tissue engineering (TE) provides an alternative option to solve limitation of organ and tissue transplantation issues. Fabrication of scaffold is a major challenge because it needs to provide a suitable medium for cell growing and drug delivery which enhances cell transplantation efficiency. The porosity, biodegradability and biocompatibility are the important properties in fabricating a scaffold. Our previous work had found that electrospinning of Polycarprolactone (PCL)/ Gelatin (GE)-based nanofibers in 14% w/v polymer solution in 18kV showed the best results in morphology, average diameters, average pore size and hydrophilicity. Hence, in this project, we are interested to study the relationship between weight ratio of PCL and GE in the same concentration (14%) to the morphology, degradation rate and porosity of nanofibers. Experimental results showed that PCL with 1.2g and GE with 0.2g was able to produce better nanofibers. The sample was then further deployed in drug (tetracycline hydrochloride) loading and it was successfully loaded proven by Energy Dispersive X-Ray (EDX) Spectrum. These nanofibers are predicted to be potentially useful for drug delivery and TE application.

Evaluation of PCL/GE-Based Electrospun Nanofibers for Tissue Engineering and Drug Delivery Application

Scaffold provides a suitable medium for cell growing and drug delivery while enhancing the cell transplantation efficiency. In this project, nanofibrous scaffolds were fabricated through electrospinning of Polycaprolactone (PCL) and Gelatin (GE). Processing parameters and solution parameters were optimized to achieve the desired properties of PCL/GE nanofibers. Scanning Electron Microscopy (SEM), water contact angle and Attenuated Total Reflectance–Fourier Transformed Infrared Spectroscopy (ATR-FTIR) were implemented to characterize the fabricated nanofibers. It was found that 14% w/v PCL/GE shows the best fibers’ diameter, pore size, contact angle and less bead formation. This sample is suitable to be further investigated for the application of tissue engineering (TE) and drug delivery system (DDS).

Polycaprolactone(PCL)/Gelati(Ge)-Based Electrospun Nanofibers for Tissue Engineering and Drug Delivery Application

Recent development of tissue engineering has been emphasized on tissue regeneration and repairing in order to solve the limitation of organ and tissue transplantation issues. Biomaterial scaffold, which plays an important role in this development, not only provides a promising alternative in order to improve the efficiency of cell transplantation in tissue engineering but also to deliver cells with growth factors and drugs into injured tissue to increase the survival of cell via drug delivery system. In this study, nanofibers were fabricated through blending of a synthetic polymer polycaprolactone (PCL) and a natural polymer Gelatin (Ge) using electrospinning technique. Processing parameters were optimized to determine the most suitable properties of PCL/Ge nanofibers. The surface morphology of PCL/Ge nanofibers were then characterized using Scanning Electron Microscopy (SEM). Six samples of nanofibers from different amount of gelatin mixed with 10% PCL (w/v) were successfully fabricated. Experimental results showed that 18kV of high voltage provided more homogenous and less beaded nanofibers. Meanwhile, the 0.8g of Ge in 10% PCL (w/v) was set as the maximum concentration while 0.2g of Ge in 10% PCL (w/v) was set as the minimum concentration to reduce the bead formation.

Electrospun Nanofibers for Tissue Engineering

Electrospun Nanofibers for Tissue Engineering

Current approaches to electrospun nanofibers for tissue engineering

The ultimate goal of tissue engineering is to replace damaged tissues by applying engineering technology and the principles of life sciences. To successfully engineer a desirable tissue, three main elements of cells, scaffolds and growth factors need to be harmonized. Biomaterial-based scaffolds serve as a critical platform both to support cell adhesion and to deliver growth factors. Various methods of fabricating scaffolds have been investigated. One recently developed method that is growing in popularity is called electrospinning. Electrospinning is known for its capacity to make fibrous and porous structures that are similar to natural extracellular matrix (ECM). Other advantages to electrospinning include its ability to create relatively large surface to volume ratios, its ability to control fiber size from micro- to nano-scales and its versatility in material choice. Although early work with electrospun fibers has shown promise in the regeneration of certain types of tissues, further modification of their chemical, biological and mechanical properties would permit future advancements. In this paper, current approaches to the development of modular electrospun fibers as scaffolds for tissue engineering are discussed. Their chemical and physical characteristics can be tuned for the regeneration of specific target tissues by co-spinning of multiple materials and by post-modification of the surface of electrospun fibers. In addition, topology or structure can also be controlled to elicit specific responses from cells and tissues. The selection of proper polymers, suitable surface modification techniques and the control of the dimension and arrangement of the fibrous structure of electrospun fibers can offer versatility and tissue specificity, and therefore provide a blueprint for specific tissue engineering applications.

Review Paper: A Review of the Cellular Response on Electrospun Nanofibers for Tissue Engineering

Electrospinning has been employed extensively in tissue engineering to generate nanofibrous scaffolds from either natural or synthetic biodegradable polymers to simulate the cellular microenvironment. Electrospinning rapidly produces fibers of the nanolength scale and the process offers many opportunities to tailor the physical, chemical, and biological properties of a material for specific applications and cellular environments. There is growing evidence that nanofibers amplify certain biological responses such as contact guidance and differentiation, however this has not been fully exploited in tissue engineering. This review addresses the cellular interactions with electrospun scaffolds, with particular focus on neural, bone, cartilage, and vascular tissue regeneration. Some aspects of scaffold design, including architectural properties, surface functionalization and materials selection are also addressed.