Pure Polycaprolactone Research Articles

3D-printed polycaprolactone-magnetic nanoparticles composite multifunctional scaffolds for bone tissue regeneration and hyperthermia treatment

Cancer management after tumor resection is characterized by two critical needs: (i) rehabilitation of the resected tissue and (ii) preventing post-surgical tumor recurrence by destroying any residual tumors. The state of the art in literature is limited because it tackles these two major priorities individually, it achieves tissue regeneration via autologous grafting and prevents tumor recurrence through chemotherapy. In this paper, extrusion 3D printing has been employed to manufacture composite multi-functional scaffolds with polycaprolactone (PCL) as a polymeric matrix and magnetic nanoparticles (MNPs) in a 0 to 50 wt% ratio, that would aid in bone regeneration and cancer management via magnetic hyperthermia treatment. The fabricated scaffolds were evaluated for their mechanical, magnetic and thermal characteristics. The Young’s modulus of the scaffolds increased multi-fold with increasing concentration of MNPs added to PCL (26.88±9.02 MPa for pure PCL to 229.06±37.05 MPa for PCL/50 wt% MNP scaffolds). PCL/MNP scaffolds displayed a directly proportional correlation between MNP concentration and saturation magnetization. While the in vitro tests showed a statistically significant cell growth of human Mesenchymal Stem Cells (hMSCs) over 7 days for all MNP concentrations, only the 50% MNP scaffold showed an increase in temperature over 41oC when subjected to an alternating magnetic field making it suitable for the hyperthermia treatment. On application of alternating magnetic fields to PCL and PCL/50 wt% MNP scaffolds, there was an increase in hMSCs proliferation and decrease in Bone cancer cells proliferation, thus proving the potential to be used as a multi-functional scaffold for post-surgical bone cancer management.  

Composite Polycaprolactone/Gelatin Nanofiber Membrane Scaffolds for Mesothelial Cell Culture and Delivery in Mesothelium Repair.

To repair damaged mesothelium tissue, which lines internal organs and cavities, a tissue engineering approach with mesothelial cells seeded to a functional nanostructured scaffold is a promising approach. Therefore, this study explored the uses of electrospun nanofiber membrane scaffolds (NMSs) as scaffolds for mesothelial cell culture and transplantation. We fabricated a composite NMS through electrospinning by blending polycaprolactone (PCL) with gelatin. The addition of gelatin enhanced the membrane's hydrophilicity while maintaining its mechanical strength and promoted cell attachment. The in vitro study demonstrated enhanced adhesion of mesothelial cells to the scaffold with improved morphology and increased phenotypic expression of key marker proteins calretinin and E-cadherin in PCL/gelatin compared to pure PCL NMSs. In vivo studies in rats revealed that only cell-seeded PCL/gelatin NMS constructs fostered mesothelial healing. Implantation of these constructs leads to the regeneration of new mesothelium tissue. The neo-mesothelium is similar to native mesothelium from hematoxylin and eosin (H&E) and immunohistochemical staining. Taken together, the PCL/gelatin NMSs can be a promising scaffold for mesothelial cell attachment, proliferation, and differentiation, and the cell/scaffold construct can be used in therapeutic applications to reconstruct a mesothelium layer.

Assessing the Viability of Polycaprolactone Mesh in Bilateral Orbital Floor Reconstruction: Insights From Le Fort II Fracture Cases.

This study aims to evaluate the effectiveness of pure polycaprolactone (PCL) mesh in reconstructing complex bilateral orbital floor fractures associated with Le Fort II fractures. PCL mesh is traditionally viewed as less suitable for severe fractures due to its perceived weakness. This study challenges that perception by demonstrating the utility of PCL mesh in high-severity cases. Two patients with Le Fort II fractures and bilateral orbital floor fractures underwent orbital reconstruction using a 3D-printed PCL mesh. The mesh was molded and inserted through subciliary or transconjunctival incisions. Orbital volumes were analyzed preoperatively and postoperatively using CT scans and a 3D Analysis program. Both cases demonstrated significant correction of orbital volume differences postoperatively, leading to improved symmetry and successful reconstruction. For case 1, the preoperative orbital volume difference of 3.2cc was reduced to 1.1cc postoperatively. For case 2, the preoperative orbital volume difference of 1.18cc was reduced to 0.4cc postoperatively. The PCL mesh provided adequate structural support and facilitated effective tissue integration. Despite the radiolucency of the PCL mesh on CT scans, volumetric analysis confirmed stable and balanced orbital volumes. Pure PCL mesh is a viable alternative for orbital floor reconstruction in severe craniofacial fractures, offering a balance of structural support and biocompatibility. To validate these findings, further research with larger samples and long-term follow-up is recommended.

Transforming Commercial Polymers into Tough yet Switchable Adhesives by Trident Photoswitch Molecule Doping: Break Adhesion-Switchability Paradox.

Here, a trident molecule doping strategy is introduced to overcome both cohesion-adhesion trade-off and adhesion-switchability conflict, transforming commercial polymers into tough yet photo-switchable adhesives. The strategy involves initial rational design of new trident photoswitch molecules namely TAzo-3 featuring azobenzene and hydroxy-terminated alkyl chains involved rigid-soft tri-branch structure, and subsequent doping into commercial polycaprolactone (PCL) via simple blending. Unique design enables TAzo-3 as a versatile dopant, not only regulating the internal and external supramolecular interaction to balance cohesion and interface adhesion for tough bonding, but also affording marked photothermal effect to facilitate rapid adhesive melting for great photo-switchability. Thus, the optimal TAzo-3-doped PCL (TAzo-3@P) displays markedly-improved bonding performance on diverse substrates compared to linear azobenzene-doped PCL and pure PCL. Impressively, TAzo-3@P on polymethyl methacrylate (PMMA) attains large room-temperature adhesion strength of 6.7MPa - surpassing most reported adhesives and many commercial adhesives on PMMA, along with easy photo-induced detachment with remarkable switch ratio of 2.09×105. Besides, TAzo-3@P can also act as "permanent" adhesives for only adhesion, demonstrating excellent multi-reusability, anti-freezing and waterproof ability. Mechanism studies unveil that the switchable adhesion is closely linked with the dopant molecule structure while rigid-soft coupled trident structures and hydroxy-terminated alkyl chains are key factors.

Engineering an Extracellular Matrix Mimic Using Hemoglobin Protein Nanofibrils.

Extracellular matrix (ECM) is essential for tissue development, providing structural support and a microenvironment that is necessary for cells. As tissue engineering advances, there is a growing demand for ECM mimics. Polycaprolactone (PCL) is a commonly used synthetic polymer for ECM mimic materials. However, its biologically inactive surface limits its direct application in tissue engineering. Our study aimed to improve the biocompatibility of PCL by incorporating hemoglobin nanofibrils (HbFs) into PCL using an electrospinning technique. HbFs were formed from bovine hemoglobin (Hb) extracted from industrial byproducts and designed to offer PCL an improved cell adhesion property. The fabricated HbFs@PCL electrospun scaffold exhibits improved fibroblast adherence, proliferation, and deeper fibroblast infiltration into the scaffold compared with the pure PCL scaffold, indicating its potential to be an ECM mimic. This study represents the pioneering utilization of Hb-sourced nanofibrils in the electrospun PCL scaffolds for tissue engineering applications.

Fabrication of biocomposite materials with polycaprolactone and activated carbon extracted from agricultural waste

In this study, activated carbon was extracted from a source of agricultural waste (wheat straw) through a chemical activation process and blended with polycaprolactone (PCL) to fabricate new biocomposite materials. Three distinct types of activated carbon, designated as C1, C2, and C3 were obtained by varying the ratio of the activation agent and wheat straw and different drying conditions. Through a comprehensive array of analytical techniques, including FTIR, XRD, BET, EDS, and FE-SEM, we determined the optimal experimental method for extracting activated carbon from wheat straw and identified the most effective type of activated carbon (C3). Based on these analyses, C3 exhibits the highest carbon content, the greatest specific surface area (386.47 m2/g), and the highest total pore volume (0.2596 cm3/g). By blending polycaprolactone with the optimal activated carbon (at concentrations of 1, 3, and 5 wt%), biocomposite samples were fabricated. The results of FTIR indicate that the biocomposite materials containing 1, 3, and 5 wt% of activated carbon exhibit no disturbing peaks. However, the sample PCL-C,1 wt%, shows significant increases in the intensity of observed peaks. XRD analyses of the fabricated biocomposite samples illustrate that the sample containing 1 wt% of activated carbon has a greater tendency for crystallization compared to the other samples. Morphological analysis of the biocomposites and the dispersion of carbon particles within them demonstrate the least amount of agglomeration in the sample with an activated carbon concentration of 1 wt%. Upon assessing the mechanical properties of biocomposites, the same sample (1 wt% of C3) demonstrates more favorable characteristics than the other samples. Furthermore, a contact angle test was conducted to gauge the biocomposite hydrophilicity, revealing a 7 degree increase in contact angle for the sample with an activated carbon concentration of 1 wt% compared to the pure PCL sample. Thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to examine the weight loss, degradation temperature, melting temperature, and glass transition temperature of the synthesized materials. These analyses indicate a marginal augmentation in both melting and glass transition temperatures for the sample with an activated carbon concentration of 1 wt%.

Fabrication and Characterization of Polycaprolactone-Baghdadite Nanofibers by Electrospinning Method for Tissue Engineering Applications.

This work investigates the essential constituents, production methods, and properties of polycaprolactone (PCL) and Baghdadite fibrous scaffolds. In this research, electrospinning was used to produce fiber ropes. In this study, the Baghdadite powder was synthesized using the sol-gel method and incorporated into PCL's polymeric matrix in formic acid and acetic acid solvents. The present work examined PCL-Baghdadite fibrous scaffolds at 1%, 3%, and 5 wt% for morphology, fiber diameter size, hydrophilicity, porosity, mechanical properties, degradability, and bioactivity. The introduction of Baghdadite nanopowder into pure PCL scaffolds reduced fiber diameter. The wetting angle decreased when Baghdadite nanopowder was added to fibrous scaffolds. Pure PCL reduced the wetting angle from 93.20° to 70.53°. Fibrous PCL scaffolds with Baghdadite nanopowder have better mechanical characteristics. The tensile strength of pure PCL fibers was determined at 2.08 ± 0.2 MPa, which was enhanced by up to 3 wt% by adding Baghdadite nanopowder. Fiber elasticity increased with tensile strength. Baghdadite at a 5% weight percentage reduced failure strain percentage. Fibers with more Baghdadite nanopowder biodegrade faster. Adding Baghdadite ceramic nanoparticles resulted in increased bioactivity and caused scaffolds to generate hydroxyapatite. The results show that Baghdadite PCL-3 wt% fibers have promising shape, diameter, and mechanical qualities. After 24 h, L-929 fibroblast cell viability was greater in the scaffold with 3% Baghdadite weight compared to the pure PCL. PCL-3 wt% Baghdadite fibers generated hydroxyapatite on the surface and degraded well. Based on the above findings, PCL fibers having 3 wt% of Baghdadite are the best sample for tissue engineering applications that heal flaws.

Mechanical, physical, and biological properties of polycaprolactone/ Mg-doped SrFe12O19 nanocomposite scaffolds for bone tissue engineering applications

Nowadays, the utilization of 3D printing has become common in the construction of composite scaffolds. In this research, the co-precipitation method was applied to synthesize pure strontium hexaferrite oxide (SrFe12O19) and magnesium-doped strontium hexaferrite oxide nanoparticles (Mg–SrFe12O19). The synthesized SrFe12O19 nanoparticles had a spherical morphology with a mean size of 60 nm and magnetization (Ms) value of 54.38 emu/g. The Mg–SrFe12O19 also had a spherical morphology with a mean particle size of 46 nm and a magnetization value of 29.89 emu/g. The produced polycaprolactone composite scaffolds containing different amounts (0, 25, 50, and 75 wt%) of reinforcement were fabricated by the 3D robocasting printing method. Based on the results of the compression test, the 25 wt% addition of the pure SrFe12O19 nanoparticles to the polycaprolactone scaffold increased the compressive strength from 2.87 to 11.68 MPa compared to the 100 wt% pure polycaprolactone scaffold. Furthermore, the polycaprolactone nanocomposite scaffold containing 25 wt% Mg–SrFe12O19 also increased the compressive strength compared to the pure polycaprolactone scaffold to 12.94 MPa. Therefore, the 25 wt% reinforced scaffold was chosen as the optimal sample. The contact angles of the pure polycaprolactone SrFe12O19 and Mg– SrFe12O19 reinforced polycaprolactone scaffolds were 77.17, 68.53, and 35.58°, respectively. The values indicate the significant effect of doping magnesium on the wettability. The degradability of the 3D-printed scaffolds containing 25 wt% of the two different reinforcements was evaluated for 28 days immersing in phosphate-buffered saline (PBS) solution. The results revealed that the degradability was higher for the Mg–SrFe12O19 after 28 days compared to the composite scaffold reinforced by pure SrFe12O19 reinforcement. Moreover, it was shown that the bioactivity and cell adhesion of MG63 cells for the scaffolds reinforced by Mg–SrFe12O19 have increased in laboratory conditions. Based on the MTT test, it was observed that both of the scaffolds were non-toxic. The results obtained in this study, suggest that polycaprolactone nanocomposite scaffolds containing 25 wt% of Mg–SrFe12O19, made by the 3D robocasting printing method, are suitable for bone tissue engineering.

Enhancement of Mechanical Properties of PCL/PLA/DMSO2 Composites for Bone Tissue Engineering

Bone tissue engineering shows potential for regenerating or replacing damaged bone tissues by utilizing biomaterials renowned for their biocompatibility and structural support capabilities. Among these biomaterials, polycaprolactone (PCL) and polylactic acid (PLA) have gained attention due to their biodegradability and versatile applications. However, challenges such as low degradation rates and poor mechanical properties limit their effectiveness. Dimethyl sulfone (DMSO2) has emerged as a potential additive to address these limitations, offering benefits such as reduced viscosity, increased degradation time, and enhanced surface tension. In this study, we investigate tailored composites comprising PLA, PCL, and DMSO2 to enhance mechanical properties and hydrophilicity. Through material characterization and mechanical testing, we found that the addition of DMSO2 led to improvements in the yield strength, modulus, and hydrophilicity of the composites. PCL and DMSO2 10, 20, and 30 wt% were premixed, and 20 wt% PCL + 10, 20, and 30 wt% DMSO2 were mixed with PLA. Specifically, PLA/PCL/DMSO2 composites exhibited higher yield strengths and moduli compared to pure PLA, pure PCL, and PLA/PCL composites. Moreover, the hydrophilicity of the composites increased with DMSO2 concentration, facilitating cell attachment. Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of –COOH and –COH bands in PLA/PCL/DMSO2 composites, indicating chemical interactions between DMSO2 and the polymer matrix. Fractography analysis revealed enhanced interface adhesion in PLA/PCL/DMSO2 composites due to the hydrogen bonding. Overall, this study demonstrates the potential of PLA/PCL/DMSO2 composites in bone tissue engineering applications, offering improved mechanical properties and enhanced cell compatibility. The findings contribute to the advancement of biomaterials for additive manufacturing in tissue engineering and regenerative medicine.

Chitin Nanocomposites for Fused Filament Fabrication: Flexible Materials with Enhanced Interlayer Adhesion.

In this work, we present a series of nanocomposites for Fused filament fabrication (FFF) based on polycaprolactone (PCL) and chitin nanocrystals (ChNCs). The ChNCs were synthesized by acid hydrolysis using HCl or lactic acid (LA). The approach using LA, an organic acid, makes the ChNCs synthesis more sustainable and modifies their surface with lactate groups, increasing their compatibility with the PCL matrix. The ChNCs characterization by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy revealed that both ChNCs presented similar morphologies and crystallinity, while differential scanning calorimetry and thermogravimetric analysis proved that they can bear temperatures up to 210 °C without degrading, which allows their processing in the manufacturing of PCL composites by twin-screw extrusion. Therefore, PCL composites in the form of filaments containing 0.5-1.0 wt % ChNCs were produced and used as feedstock in FFF, and standard tensile and flexural specimens were printed at different temperatures, up to 170 °C, to assess the influence of the ChNCs in the mechanical properties of the material. The tensile testing results showed that the presence of ChNCs enhances the strength and ductility of the PCL matrix, increasing the elongation at break around 20-50%. Moreover, the vertically printed flexural specimens showed a very different bending behavior, such that the pure PCL specimens presented a brittle fracture at 7% strain, while the ChNCs composites were able to bend over themselves. Hence, this work proves that the presence of ChNCs aims to improve the interlayer adhesion of the objects manufactured by FFF due to their good adhesive properties, which is currently a concern for the scientific community and the industrial sector.

Enhanced Marine Biodegradation of Polycaprolactone through Incorporation of Mucus Bubble Powder from Violet Sea Snail as Protein Fillers.

Microplastics' spreading in the ocean is currently causing significant damage to organisms and ecosystems around the world. To address this oceanic issue, there is a current focus on marine degradable plastics. Polycaprolactone (PCL) is a marine degradable plastic that is attracting attention. To further improve the biodegradability of PCL, we selected a completely new protein that has not been used before as a functional filler to incorporate it into PCL, aiming to develop an environmentally friendly biocomposite material. This novel protein is derived from the mucus bubbles of the violet sea snail (VSS, Janthina globosa), which is a strong bio-derived material that is 100% degradable in the sea environment by microorganisms. Two types of PCL/bubble composites, PCL/b1 and PCL/b5, were prepared with mass ratios of PCL to bubble powder of 99:1 and 95:5, respectively. We investigated the thermal properties, mechanical properties, biodegradability, surface structure, and crystal structure of the developed PCL/bubble composites. The maximum biochemical oxygen demand (BOD) degradation for PCL/b5 reached 96%, 1.74 times that of pure PCL (≈55%), clearly indicating that the addition of protein fillers significantly enhanced the biodegradability of PCL. The surface morphology observation results through scanning electron microscopy (SEM) definitely confirmed the occurrence of degradation, and it was found that PCL/b5 underwent more significant degradation compared to pure PCL. The water contact angle measurement results exhibited that all sheets were hydrophobic (water contact angle > 90°) before the BOD test and showed the changes in surface structure after the BOD test due to the newly generated indentations on the surface, which led to an increase in surface toughness and, consequently, an increase in surface hydrophobility. A crystal structure analysis by wide-angle X-ray scattering (WAXS) discovered that the amorphous regions were decomposed first during the BOD test, and more amorphous regions were decomposed in PCL/b5 than in PCL, owing to the addition of the bubble protein fillers from the VSS. The differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA) results suggested that the addition of mucus bubble protein fillers had only a slight impact on the thermal properties of PCL. In terms of mechanical properties, compared to pure PCL, the mucus-bubble-filler-added composites PCL/b1 and PCL/b5 exhibited slightly decreased values. Although the biodegradability of PCL was significantly improved by adding the protein fillers from mucus bubbles of the VSS, enhancing the mechanical properties at the same time poses the next challenging issue.

Electrospun scaffolds based on a PCL/starch blend reinforced with CaO nanoparticles for bone tissue engineering

Electrospun nanocomposite scaffolds with improved bioactive and biological properties were fabricated from a blend of polycaprolactone (PCL) and starch, and then combined with 5 wt% of calcium oxide (CaO) nanoparticles sourced from eggshells. SEM analyses showed scaffolds with fibrillar morphology and a three-dimensional structure. The hydrophilicity of scaffolds was improved with starch and CaO nanoparticles, which was evidenced by enhanced water absorption (3500 %) for 7 days. In addition, PCL/Starch/CaO scaffolds exhibited major degradation, with a mass loss of approximately 60 % compared to PCL/Starch and PCL/CaO. The PCL/Starch/CaO scaffolds decreased in crystallinity as intermolecular interactions between the nanoparticles retarded the mobility of the polymeric chains, leading to a significant increase in Young's modulus (ca. 60 %) and a decrease in tensile strength and elongation at break, compared to neat PCL. SEM-EDS, FT-IR, and XRD analyses indicated that PCL/Starch/CaO scaffolds presented a higher biomineralization capacity due to the ability to form hydroxyapatite (HA) in their surface after 28 days. The PCL/Starch/CaO scaffolds showed attractive biological performance, allowing cell adhesion and viability of M3T3-E1 preosteoblastic cells. In vivo analysis using a subdermal dorsal model in Wistar rats showed superior biocompatibility and improved resorption process compared to a pure PCL matrix. This biological analysis suggested that the PCL/Starch/CaO electrospun mats are suitable scaffolds for guiding the regeneration of bone tissue.

Sustainable biomaterials for tissue engineering: electrospun polycaprolactone fibers enriched with freshwater snail calcium carbonate and waste human hair keratin

AbstractThis study focuses on developing a sustainable and biocompatible polycaprolactone (PCL)‐based scaffold for bone tissue engineering through electrospinning, utilizing calcium carbonate (CaCO3) from Pomacea canaliculata shells and keratin from human hair, known for stimulating bone regeneration. The isolated CaCO3 has been identified to demonstrate two polymorphs, vaterite and calcite, as determined by X‐ray diffraction. The isolation of keratin from human hair was confirmed through sodium dodecyl sulfate polyacrylamide gel electrophoresis and Fourier transform infrared spectroscopy analysis, revealing the presence of α‐keratin structures around 45–50 kDa and β‐keratin structures around 55–60 kDa. According to scanning electron microscope observations, the addition of keratin to PCL fibers reduced their diameter from 457 ± 345 to 371 ± 103 nm. Further addition of calcium carbonate led to a mean diameter of 258 ± 76 nm. The melting temperature of PCL fibers containing keratin and CaCO3 was determined to be 76.17 °C via differential scanning calorimetry, while thermogravimetric analysis, conducted at temperatures up to 600 °C, revealed a remaining ash content of 9.59%. Calcium phosphate accumulation was observed to initiate on PCL fibers containing keratin and CaCO3 following a 7‐day exposure to simulated body fluid. The fibers exhibit cytocompatibility, showing no toxicity while supporting the growth and proliferation of Saos‐2 osteosarcoma cells. The results suggest that the innovative incorporation of keratin and CaCO3 into PCL nanofibers could serve as a bioactive matrix compared to pure PCL matrices, thereby offering enhanced potential for bone tissue engineering applications. © 2024 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

3D-Printed Polycaprolactone-Based Containing Calcium Zirconium Silicate: Bioactive Scaffold for Accelerating Bone Regeneration.

There is an essential clinical need to develop rapid process scaffolds to repair bone defects. The current research presented the development of calcium zirconium silicate/polycaprolactone for bone tissue engineering utilising melt extrusion-based 3D printing. Calcium zirconium silicate (CZS) nanoparticles were added to polycaprolactone (PCL) porous scaffolds to enhance their biological and mechanical properties, while the resulting properties were studied extensively. No significant difference was found in the melting point of the samples, while the crystallisation temperature points of the samples containing bioceramic increased from 36.1 to 40.2 °C. Thermal degradation commenced around 350 °C for all materials. According to our results, increasing the CZS content from 0 to 40 wt.% (PC40) in porous scaffolds (porosity about 55-62%) improved the compressive strength from 2.8 to 10.9 MPa. Furthermore, apatite formation ability in SBF solution increased significantly by enhancing the CZS percentage. According to MTT test results, the viability of MG63 cells improved remarkably (~29%) in PC40 compared to pure PCL. These findings suggest that a 3D-printed PCL/CZS composite scaffold can be fabricated successfully and shows great potential as an implantable material for bone tissue engineering applications.

Effect of filler orientation on mechanical and thermal properties of microwave absorbent 3D printed polycaprolactone/carbonyl iron particle composites

A thorough investigation was conducted in the present work on the mechanical and thermal characteristics of polycaprolactone/carbonyl iron particle composites. For composite fabrication, 3D printing technique was utilized. The fabricated composites were categorized as oriented, non-oriented and polycaprolactone samples based on orientation and concentration of filler particle. To evaluate the effect of orientation of carbonyl iron particle, two orientation directions, viz. parallel orientation, and perpendicular orientation with respect to loading direction were tried. The sample with parallel orientation exhibited the highest tensile strength followed by 90° orientation and pure polycaprolactone samples respectively. Oriented composites exhibited elevated dynamic modulus in comparison to the composites without orientation. The oriented composites demonstrated stiffness and tensile strength in the order of 13.66 ± 0.94 MPa and 3.79 ± 0.26 MPa respectively. The proposed methodology in the present study can be used to align carbonyl iron fillers in polymer matrix to tailor the mechanical, viscoelastic, and degradation properties.

Polycaprolactone-Based Composite Electrospun Nanofibers as Hybrid Biomaterial Systems Containing Hydroxyl- or Carboxylic Acid-Functionalized Multiwall Carbon Nanotubes

Composite electrospun nanofibers based on polycaprolactone (PCL) have shown promise in various biomedical applications due to their unique properties. This study investigates the effects of incorporating hydroxyl (–OH)- or carboxylic acid (–COOH)-functionalized multiwall carbon nanotubes (MWCNTs) into PCL matrices. Two types of functionalized additives, MWCNT-OH and MWCNT-COOH, were used at different concentrations (0.06 and 0.12 wt%). Various characterization techniques including FTIR, XRD, AFM, SEM, water contact angle analysis, and tensile strength testing were employed to evaluate changes in nanofiber morphology, crystallinity, surface topography, wettability, and mechanical properties. In addition, in vitro cytotoxicity assays were conducted using HUVECs and L929 fibroblasts over 1-, 3-, and 5-day intervals. This study represents a novel examination of (–OH)- and (–COOH)-functionalized MWCNTs as additives in electrospun PCL biopolymer matrices. The findings indicate that incorporating small amounts of (–OH)- or (–COOH)-functionalized MWCNTs enhances the physicochemical characteristics of PCL nanofibers, making them more suitable for biomedical applications. While both types of functionalized MWCNT additives improved properties compared to pure PCL nanofibers, (–COOH)-functionalized MWCNT-incorporated nanofibers exhibited the most favorable features. In conclusion, this research highlights the potential of tailored PCL-based composite nanofibers containing functionalized MWCNTs as advanced biomaterial systems for biomedical applications, contributing to the development of innovative biomaterials for diverse biomedical contexts.

Effect of Mg incorporation on the properties of PCL/Mg composites for potential tissue engineering applications

Polycaprolactone (PCL) is a biocompatible polymer readily moldable into various shapes and designs. However, its low mechanical strength and slow biodegradation restrict its use in tissue engineering. Magnesium (Mg), a biocompatible metal with excellent osteoconductivity and biodegradability, is a promising choice for tissue engineering applications. This study investigates the influence of Mg incorporation on the properties of PCL/Mg composites, aiming to evaluate their suitability for 3D-printable (3DP) tissue engineering applications. We synthesized a series of PCL/Mg composites with varying Mg concentrations and characterized their mechanical, thermal, and degradation properties. According to microscopic analysis of the composite films, the Mg particles are dispersed consistently throughout all the compositions. The findings demonstrated that adding Mg influenced PCL’s mechanical and thermal properties. The mechanical test results showed that the tensile strength of 15% Mg composite filaments improved by around 10% compared to the neat PCL filaments. However, the elastic modulus decreased by around 50% for the same composition. The thermal study revealed a significant reduction in the degradation temperature from above 400°C for pure PCL to around 300°C for PCL/Mg composite having 15% Mg. Additionally, the weight loss during in vitro degradation showed that the presence of Mg had significantly increased the degradation rate of composite samples. Also, Mg incorporation influences cell adhesion, with better attachment observed for 10% Mg 3DP samples. Overall, PCL/Mg composites offer a solution to overcome the limitation of low thermo-mechanical properties typically associated with the PCL.

Novel polycaprolactone-based biomimetic grafts enriched with graphene oxide and cerium oxide: Exploring improved osteogenic potential

In bone tissue engineering, the development of advanced biomaterials is crucial to address the challenges associated with the treatment and regeneration of bone defects. This study presents a novel polymeric nanocomposite consisting of Polycaprolactone (PCL) integrated with graphene oxide (GO) and cerium oxide (CeO2) nanoparticles, aiming to comprehensively explore its multifaceted potential for bone tissue engineering applications. The physicochemical properties of the composite films were analyzed. Biodegradation studies showed superior degradability to pure PCL due to added hydrophilic features and increased nanofiller-induced surface porosity. The remarkable improvement in mechanical stability is attributed to the uniform dispersion of nanofillers. Assessments of surface wettability, demonstrate a noteworthy shift towards heightened hydrophilicity, rendering a more conducive environment for biomolecules. The hybrid polymer nanocomposite exhibits remarkable hemocompatibility, antibacterial properties, antioxidant activity, and excels in facilitating apatite deposition and promoting osteogenic differentiation. Biomineralization investigations and ARS assay underscore the nanocomposite's exceptional ability to promote apatite deposition, a pivotal mineral in bone formation, owing to the altered surface properties introduced by the nanofillers. The ALP findings imply that the PCL-GO-CeO2 nanocomposite actively supports and accelerates the process of osteogenic differentiation in MSCs, indicating its potential utility in bone tissue engineering. Additionally, cell culture studies conducted on HOS and rBMSC cell lines validate the nanocomposite's excellent cell viability, attachment, and proliferation, affirming its biocompatibility and potential for bone tissue engineering. Collectively, these findings establish PCL-GO-CeO2 nanocomposite as a favourable option for enhancing bone regeneration.

Novel Bioresorbable Drug-Eluting Mesh Scaffold for Therapy of Muscle Injury.

A novel bioresorbable drug-eluting polycaprolactone (PCL) mesh scaffold was developed, utilizing a solvent-cast additive manufacturing technique, to promote therapy of muscle injury. The degradation rate and mechanical properties strength of the PCL mesh were characterized after immersion in a buffer solution for different times. The in vitro release characteristics of vancomycin, ceftazidime, and lidocaine from the prepared mesh were evaluated using a high-performance liquid chromatography (HPLC) assay. In addition, the in vivo efficacy of PCL meshes for the repair of muscle injury was investigated on a rat model with histological examinations. It was found that the additively manufactured PCL meshes degraded by 13% after submission in buffered solution for four months. All PCL meshes with different pore sizes exhibited greater strength than rat muscle and survived through 10,000 cyclic loadings. Furthermore, the meshes could offer a sustained release of antibiotics and analgesics for more than 3 days in vitro. The results of this study suggest that drug-loaded PCL mesh exhibits superior ability to pure PCL mesh in terms of effectively promoting muscle repair in rat models. The histological assay also showed adequate biocompatibility of the resorbable meshes. The additively manufactured biodegradable drug-eluting meshes may be adopted in the future in humans for the therapy of muscle injuries.

3D-printed polycaprolactone/tricalcium silicate scaffolds modified with decellularized bone ECM-oxidized alginate for bone tissue engineering

The treatment of large craniofacial bone defects requires more advanced and effective strategies than bone grafts since such defects are challenging and cannot heal without intervention. In this regard, 3D printing offers promising solutions through the fabrication of scaffolds with the required shape, porosity, and various biomaterials suitable for specific tissues. In this study, 3D-printed polycaprolactone (PCL)-based scaffolds containing up to 30 % tricalcium silicate (TCS) were fabricated and then modified by incorporation of decellularized bone matrix- oxidized sodium alginate (DBM-OA). The results showed that the addition of 20 % TCS increased compressive modulus by 4.5-fold, yield strength by 12-fold, and toughness by 15-fold compared to pure PCL. In addition, the samples containing TCS revealed the formation of crystalline phases with a Ca/P ratio near that of hydroxyapatite (1.67). Cellular experiment results demonstrated that TCS have improved the biocompatibility of PCL-based scaffolds. On day 7, the scaffolds modified with DBM and 20 % TCS exhibited 8-fold enhancement of ALP activity of placenta-derived mesenchymal stem/stromal cells (P-MSCs) compared to pure PCL scaffolds. The present study's results suggest that the incorporation of TCS and DBM-OA into the PCL-based scaffold improves its mechanical behavior, bioactivity, biocompatibility, and promotes mineralization and early osteogenic activity.