Polycaprolactone Nanofibrous Mats Research Articles

Combination of mesenchymal stem cell sheet with poly-caprolactone nanofibrous mat and Gelfoam increased osteogenesis capacity in rat calvarial defect

Introduction: To date, different strategies have been used for co-transplantation of cell-loaded biomaterials for bone tissue regeneration. This study aimed to investigate the osteogenic properties of adipose-derived-mesenchymal stem cell (AD-MSC) sheets combined with nanofibrous poly-caprolactone (PCL) mat and Gelfoam in rats with calvarial bone defect. Methods: Calvarial critical-size defects were induced in male rats. Animals were classified into Control, Gelfoam, Gelfoam/PCL nanofiber, Gelfoam/AD-MSC sheet, and Gelfoam/PCL nanofiber/AD-MSC sheet groups. After 3 months, rats were sacrificed and the regeneration rate was evaluated. Results: Almost all groups showed bone regeneration properties, but the volume of newly formed bone was higher in groups that received Gelfoam/AD-MSC and Gelfoam/PCL nanofiber/AD-MSC sheets (P < 0.05). The application of Gelfoam/PCL nanofiber/AD-MSC sheets not only increased bone thickness, bone volume/total bone volume (BV/TV) ratio, strong Hounsfield Unit (HU), but also led to the formation of ossified connective tissue with wrinkled patterns. Conclusion: The current study indicated that the Gelfoam/PCL nanofiber/AD-MSC sheet provides a suitable platform for effective osteogenesis in calvarial bone defects.

In vitro and in vivo assessment of gallic acid-chitosan/polycaprolactone conjugate electrospun nanofibers for wound healing

The development of innovative multifunctional wound healing materials based on natural bioactives has attracted a great deal of attention in recent years due to their ability to potentiate the healing process and minimize the challenges linked with conventional wound dressings. The current study demonstrates the development and evaluation of a novel nanofibrous wound healing mat made of Gallic acid-chitosan conjugate (GAC) incorporated within a polycaprolactone (PCL) matrix using an electrospinning technique. The GAC conjugate was synthesized by green synthesis using a free radical polymerization reaction to improve the chitosan's free radical scavenging properties. FTIR, DSC, XRD, and UV spectral analysis characterized the formation of GAC conjugate. The red shift observed in the UV spectrum suggested alterations in electronic transitions resulting from the creation of covalent bonds between Chitosan (CA) and Gallic acid (GA). The appearance of broader and weaker peaks in DSC and the reduced crystallinity in XRD spectrum, signify structural modifications, thereby providing valuable insights into the interaction and structural changes occurring in the GAC conjugates.The SEM image revealed a porous flake-like structural network of GAC conjugate due to the reduced intermolecular hydrogen bonding between them. The functional layer of the nanofibrous mat was produced by electrospinning GAC conjugate with polycaprolactone (PCL) to provide mechanical integrity to the nanofibrous mat. The electrospun nanofibers were characterized using FTIR, DSC, and SEM and evaluated for cell cytotoxicity, angiogenesis, and in vivo wound healing potential in female Wistar rats. The FTIR spectra confirmed the presence of GAC conjugate in the nanofibers, validating the conjugation process. The results demonstrated the successful incorporation of GAC conjugate within the PCL nanofibrous mat, thereby confirming the improvement in the biological properties of the mats. The nanofibrous mat showed angiogenesis activity in the yolk sac membrane assay confirming the property of nanofibers to facilitate cellular adhesion, migration and promotion of angiogenesis with no cytotoxic effect on the viability of mouse stromal cells. On the sixteenth day of therapy, wounds dressed with GAC/PCL nanofibrous mat exhibited a significant improvement in the percent wound closure (94.43%) as compared to the control group (p < 0.05). These results supported the application of GAC/PCL as a novel biomaterial for wound dressing to accelerate the process of wound healing.

Flavonoids, phenolics, and tannins loaded polycaprolactone nanofibers (NF) for wound dressing applications

Triphala is one of the commonly used ayurvedic formulations for gastrointestinal disorders. In Ayurveda, Triphala water has been used to wash wounds as an antimicrobial agent for wound healing. In this study, the wound healing property of Triphala was further enhanced by mixing equal proportions of medicinal plants like Acacia catechu, Glycyrrhiza glabra Azadirachta indica, and Coscinium fenestratum. The polyherbal extract was prepared from the new polyherbal formulation using a methanol-chloroform solvent mixture and analysed for its quality and quantity of phytochemicals. Then, the polyherbal extract at 1%, 3%, and 5% concentration was mixed with 10% polycaprolactone (PCL) polymer and converted into poly-herbal extract-loaded nanofibers using an electrospinning technique. The prepared nanofibers were characterized by FTIR, XRD, FESEM, contact angle, and water absorption. Further, the biological properties like antimicrobial activity and biocompatibility were also analysed. Finally, the in-vivo wound healing efficiency was studied using an animal model. The FTIR analysis reveals the presence of unique phytochemicals of plant extracts. Further, the FESEM confirms the presence of the drug on the surface of nanofibers. From the XRD, the reduction in crystallinity was observed due to herbal drug incorporation. Further, contact angle, water absorption also proved the absorbing ability of polyherbal-loaded nanofibers. The polycaprolactone-polyherbal (PCL-PHF) formulation of 3% and 5% loaded nanofibers shows faster wound healing compared to the control and standard. In addition, the polyherbal drug-loaded polycaprolactone shows faster granulation tissue formation and collagen synthesis compared to the standard group. The antioxidant property of the patch protects the wound from lipid peroxides and myeloperoxidase. Overall, the antimicrobial, antioxidant, and anti-inflammatory property of polyherbal extract aids in faster wound healing. This finding suggests that the polyherbal drug-loaded polycaprolactone nanofibrous mats could be used as an effective candidate for the treatment of open wounds.

Facile modification of polycaprolactone nanofibers with egg white protein

Synthetic polymers remain to be a major choice for scaffold fabrication due to their structural stability and mechanical strength. However, the lack of functional moieties limits their application for cell-based therapies which necessitate modification and functionalization. Blending synthetic polymers with natural components is a simple and effective way to achieve the desired biological properties for a scaffold. Herein, nanofibrous mats made of polycaprolactone (PCL) and egg white protein (EWP) blend were developed and further evaluated for use as a scaffold for tissue engineering applications. Homogeneous distribution of EWP was achieved throughout the nanofibrous mats, as shown by immunohistochemistry. ATR-FTIR analysis and contact angle measurements have further confirmed the presence of EWP on the surface of the samples. The swelling test showed that PCL/EWP nanofibers have higher water uptake than PCL nanofibrous mats. Also, EWP addition on the nanofibrous mats resulted in an increase in the tensile strength and Young’s modulus of the mats, indicating that the presence of protein can greatly enhance the mechanical properties of the mats. A significantly higher, more uniform, and dispersed cell spreading was observed on days 7 and 14 than that on neat PCL mats, demonstrating the importance of providing the required cues for cell homing by the availability of EWP. Hence, EWP is shown to be a simple and low-cost source for the functionalization of PCL nanofibrous mats. EWP is, therefore, a facile candidate to enhance cellular interactions of synthetic polymers for a wide range of tissue engineering applications.

Ecofriendly antimicrobial Acalypha indica leaf extract immobilized polycaprolactone nanofibrous mat for food package applications

A novel antimicrobial food package material was designed by immobilization of medicinal plant Acalypha indica leaf extract on the polycaprolactone (PCL) nanofibrous mats which prevent the food materials from microbial contamination. The morphology of prepared mats was characterized by scanning electron microscope (SEM) images. The loading of plant extract onto the PCL nanofibrous mats was confirmed by XRD spectrum. The porosity percentage of the prepared electrospun PCL nanofibrous mats has been found from SEM image using ImageJ software. The A. indica extract immobilized PCL nanofibrous mats were analyzed for its thermal stability and anti-bacterial activity. The immobilized nanofibrous mats were tested with food samples (carrot pieces) inoculated in bacterial culture in order to check for their microbial inhibitory effect and monitored its shelf life period. The results of the work declare that the A. indica leaf extract immobilized electrospun PCL nanofibrous mat act as an effective antimicrobial food package material. Practical applications Nowadays, the microbial attack on foods may lead to major health issues worldwide. Many efforts have been taken for preservation and inhibition of such microbial attack on foods. The results of the present work reveal that the package material prepared by immobilization of natural antimicrobial plant extract into polycaprolactone nanofibrous mats vanish the bad odor emerges from foods due to microbial attack and increase the food shelf life period as well as food quality. Therefore, the prepared immobilized nanofibrous mats will serve as a promising package material for foods.

Deposition penetration depth and sticking probability in plasma polymerization of cyclopropylamine

Understanding the role of substrate geometry is vital for a successful optimization of low-pressure plasma polymerization on non-planar substrates used in bioapplications, such as porous materials or well plates. We investigated the altered transport of film-forming species and properties of the coatings for a cyclopropylamine and argon discharge using a combined analysis of the plasma polymer deposition on flat Si pieces, culture wells, microtrenches, a macrocavity, porous hydroxyapatite scaffolds and electrospun polycaprolactone nanofibrous mats. The aspect ratio of the well structures impacted mainly the deposition rate, whereas the film chemistry was affected only moderately. A large deposition penetration depth into the porous media indicated a relatively low sticking probability of film-forming species. A detailed analysis of microtrench step coverage and macrocavity deposition disproved the model of film-forming species with a single overall sticking probability. At least two populations with two different sticking probabilities were required to fit the experimental data. A majority of the film-forming species (76%) has a large sticking probability of 0.20±0.01, while still a significant part (24%) has a relatively small sticking probability of 0.0015±0.0002. The presented methodology is widely applicable for understanding the details of plasma-surface interaction and successful applications of plasma polymerization onto complex substrates.

Plasma treatment effects on bulk properties of polycaprolactone nanofibrous mats fabricated by uncommon AC electrospinning: A comparative study

The prominent success of polycaprolactone (PCL) electrospun nanofibrous mats (ENM) has expanded the use of PCL over other polymers for tissue engineering applications. However, the major challenge in the design of a nanofibrous scaffold is to modify its surface properties while preserving its bulk properties. Therefore, the first part of the study is focused on the fabrication of PCL-ENMs by alternating-current electrospinning using the following solvent systems: formic acid, formic acid/acetic acid (1/1) and formic acid/acetic acid/acetone (1/1/1). While the second part is focused on an nm-thick surface chemical modification via medium pressure argon and nitrogen plasma treatment, and the third part is dedicated to investigating the morphology, wettability, surface functional groups, crystallite size, crystallinity, crystallization, and melting temperature of plasma-treated nanofibers. Samples were characterized using scanning electron microscopy (SEM), water contact angle analysis (WCA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and differential scanning calorimetry (DSC). WCA and SEM results showed that plasma treatments significantly improve the wettability of the PCL ENMs without compromising their surface morphology. XPS analysis revealed that argon and nitrogen gases are responsible for a substantial increase in polar oxygen and nitrogen functional groups respectively. Out of the six plasma-treated PCL ENMs understudy, the argon plasma-treated sample showed superior hydrophilicity (from 136° to ~35°) followed by nitrogen plasma treatment (from 136° to ~42°). It was also found from XRD that the crystallite size was not significantly affected by the conducted plasma treatments. Moreover, the degree of crystallinity was also not altered by the plasma treatments, as was observed by DSC and FTIR. The conducted experiments showed that the surface properties of the PCL ENMs could be positively affected while maintaining their beneficial bulk properties thereby making these plasma-modified ENMs excellent candidates in multiple biomedical and tissue engineering applications.

Effect of three different amines on the surface properties of electrospun polycaprolactone mats

The adequacy of biomaterials is essential to generate scaffolds suitable for tissue engineering studies. The electrospinning technique is a resourceful, quick and cheap way to obtain polycaprolactone (PCL) scaffolds with an architecture with porosity and adequate properties to ensure the survival of cells. However, some obstacles need to be overcome, such as the hydrophilicity of this polymer. In this study, we produced electrospun PCL nanofibrous mats and submitted them to aminolysis with three different diamines in order to generate hydrophilic cell-friendly scaffolds. The nanofibrous mats were characterized by their morphology, thermal and mechanical properties and, lastly, seeded with Human Adipose-Derived Stem Cells (hADSC) to observe the influence of the introduced amino groups in the polymeric matrix. The obtained results suggest a successful insertion of amino groups in the polymeric matrix, without being too detrimental to its morphology and intrinsic properties. Furthermore, the aminolyzed mats displayed a qualitative increase of cells attached to the nanofibrous mats.

Radially patterned polycaprolactone nanofibers as an active wound dressing agent.

BackgroundThe objectives of this study were to design polycaprolactone nanofibers with a radial pattern using a modified electrospinning method and to evaluate the effect of radial nanofiber deposition on mechanical and biological properties compared to non-patterned samples.MethodsRadially patterned polycaprolactone nanofibers were prepared with a modified electrospinning method and compared with randomly deposited nanofibers. The surface morphology of samples was observed under scanning electron microscopy (SEM). The tensile properties of nanofibrous mats were measured using a tabletop uniaxial testing machine. Fluorescence-stained human bone marrow stem cells were placed along the perimeter of the radially patterned and randomly deposited. Their migration toward the center was observed on days 1, 4, and 7, and quantitatively measured using ImageJ software.ResultsOverall, there were no statistically significant differences in mechanical properties between the two types of polycaprolactone nanofibrous mats. SEM images of the obtained samples suggested that the directionality of the nanofibers was toward the central area, regardless of where the nanofibers were located throughout the entire sample. Florescence images showed stronger fluorescence inside the circle in radially aligned nanofibers, with significant differences on days 4 and 7, indicating that migration was quicker along radially aligned nanofibers than along randomly deposited nanofibers.ConclusionsIn this study, we successfully used modified electrospinning to fabricate radially aligned nanofibers with similar mechanical properties to those of conventional randomly aligned nanofibers. In addition, we observed faster migration along radially aligned nanofibers than along randomly deposited nanofibers. Collectively, the radially aligned nanofibers may have the potential for tissue regeneration in combination with stem cells.

Incorporation of Silver Sulfadiazine into An Electrospun Composite of Polycaprolactone as An Antibacterial Scaffold for Wound Healing in Rats.

Objective Fabrication of an antibiotic-loaded scaffold with controlled release properties for wound dressing is one of tissue engineering challenges. The aim of this study was to evaluate the wound-healing effectiveness of 500-µm thick polycaprolactone (PCL) nanofibrous mat containing silver sulfadiazine (SSD) as an antibacterial agent. Materials and Methods In this experimental study, an electrospun membrane of PCL nanofibrous mat containing 0.3% weight SSD with 500 µm thickness, was prepared. Morphological and thermomechanical characteristics of nanofibers were evaluated. Drug content and drug release properties as well as the surface hydrophobicity of the nanofibrous membrane were determined. Antimicrobial properties and cellular viability of the scaffold were also examined. A full thickness wound of 400 mm2 was created in rats, to evaluate the wound-healing effects of PCL/SSD blend in comparison with PCL and vaseline gas used as the control group. Results SSD at a concentration of 0.3% improved physicochemical properties of PCL. This concentration of SSD did not inhibit the attachment of human dermal fibroblasts (HDFs) to nanofibers in vitro, but showed antibacterial activity against Gram-positive Staphylococcus aureus (ST) and Gram-negative Pseudomonas aeruginosa (PS). Overall, results showed that SSD improves characteristics of PCL nanofibrous film and improves wound-healing process in one-week earlier compared to control. ConclusionCytotoxicity of SSD in fabricated nanofibrous mat is a critical challenge in designing an effective wound dressing that neutralizes cellular toxicity and improves antimicrobial activity. The PCL/SSD nanofibrous membrane with 500- µm thickness and 0.3% (w/v) SSD showed applicable characteristics as a wound dressing and it accelerated wound healing process in vivo.

Characterization of polyherbal-incorporated polycaprolactone nanofibrous mat for biomedical applications

The polyherbal-loaded polycaprolactone nanofibrous mat was prepared by electrospinning technique, and physical and chemical characteristics of nanofibrous mats were studied using scanning electron microscopy, x-ray diffraction, thermogravimetric analyzer, and Fourier transform infrared spectroscopy. The presence of various phytochemicals in the crude monoherbal and polyherbal extracts was analyzed. The antimicrobial activity and biocompatibility of the polyherbal-loaded nanofibrous mats were studied. The drug release pattern of the polyherbal-loaded nanofibrous mats was studied at different time intervals. The 5% drug-loaded nanofibrous mat shows higher sustainable drug release rate than 1% and 3% drug-loaded nanofibrous mats. The cell viability was found to be 98.91%, 98.77%, 98.5%, and 98.22% for polycaprolactone and 1%, 3%, and 5% for polyherbal-loaded nanofibrous mats, respectively.

Incorporation of rectorite into porous polycaprolactone/TiO2 nanofibrous mats for enhancing photocatalysis properties towards organic dye pollution

TiO 2 , as a kind of traditional photocatalytic material, has been widely used in wastewater treatments due to its cost-efficiency, high stability and low toxicity. However, it could hardly be reused and might lead to secondary pollution. In the study, porous electrospun polycaprolactone (PCL) fibrous mats were used as carriers for the capacity and dispersion of TiO 2 . The porous PCL mats could provide large contact area for high photocatalytic efficiency of TiO 2 . Besides, the addition of rectorite (REC) could reduce the diameters of fibers and enlarge the specific surface area, which might be beneficial to photocatalysis . More importantly, REC played an important role in improving the function of porous PCL/TiO 2 mats, which contributed to a high rate of photocatalytic degradation. The results indicated that porous PCL/TiO 2 /REC mats could serve as potentially excellent photocatalysts in the degradation of organic dyes. • Porous polycaprolactone nanofibrous mats were used as carriers for the capacity and dispersion of TiO 2 . • The mats exhibited well dispersion of TiO 2 and larger surface areas with the introduction of rectorite. • The rectorite-induced stabilization of the anatase phase could enhance the photocatalytic activity.

Tailoring Biodegradation of Fine Grained AZ31 Alloy Implants by Nanofibrous Coatings

Fine grained AZ31 magnesium alloy treated with HNO3 was coated with electrospun polycaprolactone (PCL) nanofibres. Entire surface of the alloy was found to be coated with non-woven PCL nanofibrous mat with an average fiber diameter of 400 nm. The effect of coating on biodegradation and biomineralization of the samples were studied by immersion test conducted in supersaturated simulated body fluid (SBF 5×). The immersion test showed that the PCL coating reduced degradation rate. The surface of the immersed samples analyzed using scanning electron microscope (SEM) fitted with X-ray energy dispersive spectroscopy (EDS) confirmed that the PCL coating protects the surface from chloride ion attack and avoid pitting corrosion. Moreover the coated samples also had calcium phosphate (CaP) phases adhering on the surface which are essential for bone implant applications. Hence, nanofibrous PCL coating on fine grained AZ31 may be tried for degradable metallic implant applications to have a controlled degradation rate and enhancement of bioactivity.

Modification of Polycaprolactone Nanofibrous Mat by Laminin Protein and Its Cellular Study

Modification of Polycaprolactone Nanofibrous Mat by Laminin Protein and Its Cellular Study

Electrospun Nanofibrous Polymer Coated Magnesium Alloy for Biodegradable Implant Applications

In the present study, AZ31 magnesium alloy sheets were chemically treated and then coated with polycaprolactone (PCL) nanofibers by electrospinning technique to fabricate biodegradable magnesium based implants. PCL nanofibrous mat of average fiber thickness 110nm covered the entire substrate after coating. Wettability studies carried by contact angle measurements indicated improved hydrophilicity for chemically treated AZ31 due to the formation of magnesium hydroxide and moderate hydrophobicity for polymer coated AZ31. Bio-mineralization and degradation studies conducted in super saturated simulated body fluids clearly showed improved corrosion resistance for both the chemically treated and polymer coated AZ31 compared with annealed AZ31. Among all the samples, nano-fiber coated AZ31 has shown excellent corrosion resistance.