Improved Cell Adhesion Research Articles

Enhanced Osteogenesis in 2D and 3D Culture Systems Using RGD Peptide and α-TCP Phase Transition within Alginate-Based Hydrogel.

Cell-laden hydrogels have been extensively investigated in various tissue engineering fields bytheir potential capacity to deposit numerous types of cells in a specific area. They are largely used in soft-tissue engineering applications because of their low mechanical strength. In addition, sodium alginate is well-known for its encapsulation, loading capacity and for being easily controllable; however, it lacks cell-binding ligands and hence the ability to adhere cells. In this study, it is aimed to enhance osteogenesis in cells encapsulated in alginate and improve its mechanical properties by introducing a synthetic peptide and calcium phosphate phase transition. To increase cell-hydrogel interactions and increasing cell viability, an RGD peptide is added to a photocrosslinkable methacrylate-modified alginate, and alpha-tricalcium phosphate (α-TCP) is added to the hydrogel to increase its mechanical strength via phase transition. Cell proliferation, growth, and differentiation are assessed in both 2D and 3D cell cultures. The addition of α-TCP significantly improved the mechanical properties of the hydrogel. Moreover, the RGD peptide and α-TCP showed a synergistic effect with significantly improved cell adhesion and osteogenesis in both 2D and 3D cell cultures. Therefore, the functional hydrogel developed in this study can potentially be used for bone tissue regeneration.

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.

Effects of Physically Adsorbed and Chemically Immobilized RGD on Cell Adhesion to a Hydroxyapatite Surface

The strategies used to associate peptide arginylglycylaspartic acid (RGD) with calcium phosphate grafts to enhance cell–biomaterial interactions have been controversial in the literature. Several works have demonstrated that RGD-functionalized hydroxyapatite (HA) surfaces improve cell adhesion, whereas others claim that RGD-loaded HA has an inhibitory effect when serum is present in the biological medium. To investigate such contradictory results, we associated RGD with the HA surface using physical adsorption and chemical bonding methods and evaluated the cell adhesion and spreading in pre-osteoblasts culture with and without fetal bovine serum (FBS). The effect of functionalization methods on the physicochemical characteristics of both surfaces was analyzed using multiscale techniques. Adsorption assays of serum allowed us to estimate the impact of the association method on the HA surface’s reactivity. Physically adsorbed RGD did not increase the number of adhered cells due to the weak interactions between the peptide and the surface. Although chemical binding stabilizes RGD on the HA, the functionalization procedure covered the surface with molecules such as (3-aminopropyl)triethoxysilane (APTEs) and carbodiimide, changing the surface’s chemical activity. Serum protein adsorption decreased by 90%, revealing a significant reduction in the surface interactions with molecules of the biological medium. The present study’s findings showed that the RGD’s physical association with HA did not improve cell adhesion and that this phenomenon is highly dependent on the presence of serum proteins.

Surface-Conjugated Galactose on Electrospun Polycaprolactone Nanofibers: An Innovative Scaffold for Uterine Tissue Engineering.

The uterus, a vital organ in the female reproductive system, nurtures and supports developing embryos until maturity. This study focuses on addressing uterine related problems by creating a nanofibrous scaffold to regenerate uterine myometrial tissue, closely resembling the native extracellular matrix (ECM) for enhanced efficacy. To achieve this, we utilized polycaprolactone (PCL) as a biomaterial and employed an electrospinning technique to generate PCL nanofibers in both random and aligned orientations. Due to the inherent hydrophobic nature of PCL nanofibers, a two-step wet chemistry surface modification technique is used, involving the conjugation of galactose onto them. Galactose, a lectin-binding sugar, was chosen to enhance the scaffold's hydrophilicity, thereby improving cell adhesion and fostering l-selectin-based interactions between the scaffold and uterine cells. These interactions, in turn, activated uterine fibroblasts, leading to ECM remodeling. The optimized electrospinning process successfully generated random and aligned nanofibers. Subsequent surface modification was carried out, and the modified scaffold was subjected to various physicochemical characterization, such as the ninhydrin assay, enzyme-linked lectin assay techniques that revealed successful galactose conjugation, and mechanical characterization to assess any changes in material bulk properties resulting from the modification. The tensile strength of random galactose-modified PCL fibers reached 0.041 ± 0.01 MPa, outperforming random unmodified PCL fibers (0.026 ± 0.01 MPa), aligned unmodified PCL fibers (0.011 ± 0.001 MPa), and aligned modified PCL fibers (0.016 ± 0.002 MPa). Cytocompatibility studies with human uterine fibroblast cells showed enhanced viability and proliferation on the modified scaffolds. Initial pilot studies were attempted in the current study involving subcutaneous implantation in the dorsal area of Wistar rats to assess biocompatibility and tissue response before proceeding to intrauterine implantation indicated that the modification did not induce adverse inflammation in vivo. In conclusion, our study introduces a surface-modified PCL nanofibrous material for myometrial tissue engineering, offering promise in addressing myometrial damage and advancing uterine health and reproductive well-being.

The effects of droplet stabilization by surfactants and nanoparticles on leakage, cross-talk, droplet stability, and cell adhesion.

Partially fluorinated nanoparticles (FNPs) have been proposed as a promising alternative for stabilising aqueous droplets in fluorinated oils. The exceptional energetic stability of FNPs at the droplet interface holds the potential for minimising leakage, enhancing stability, and promoting improved cell adhesion. However, their lower diffusion coefficient compared to surfactants presents challenges in achieving rapid droplet stabilisation, which is important in microfluidics applications. While several studies have focused on some of these aspects, a comprehensive study and direct comparison with conventional fluorosurfactants is still missing. In this manuscript, we undertake an examination and comparison of four crucial facets of both FNP- and surfactant-stabilised droplets: leakage of compounds, emulsion stability, droplet formation dynamics and cell adhesion. Contrary to what has previously been claimed, our findings demonstrate that FNPs only reduce leakage and cross-talk in very specific cases (e.g., resorufin), failing to provide enhanced compartmentalisation for highly hydrophobic dyes (e.g., rhodamine dyes). On the other hand, FNP-stabilised droplets indeed exhibit greater long-term stability compared to their surfactant-stabilised counterparts. Regarding the size of droplets generated via a diversity of microfluidic methods, no significant differences were observed between FNP-stabilised and surfactant-stabilised droplets. Finally, the previously reported improvements in cell adhesion and spreading on FNP-stabilised interfaces is limited to flat oil/water (o/w) interfaces and could not be observed within droplets. These comprehensive analyses shed light on the nuanced performance of FNPs and commercial fluorosurfactants as stabilising agents for aqueous droplets in fluorinated oils, contributing valuable insights for choosing the correct formulation for specific droplet-based microfluidics applications.

Ion-induced electrospinning of hierarchical spiderweb-like bioscaffolds

Tissue engineered scaffolds need to possess various functionalities, including biocompatibility, mechanical support, bioactivity, and vascularization. The design and fabrication of bioscaffolds to attain mutual coordination among these functionalities with minimal processing complexity are a highly challenging but rewarding task. In this study, a simple, effective one-step electrospinning method was developed to fabricate hierarchical spiderweb-like bioscaffolds that achieve both superior biological and mechanical functionalities. By incorporating ionic drugs of deferoxamine mesylate and lithium chloride, the spiderweb-inspired structures with adjustable coverages (up to 100 %) were successfully created, imparting the fibrous bioscaffolds with remarkable tensile strengths (∼88.28 MPa). The strengthening mechanisms endowed by the spiderweb structure in optimizing stress distribution to delay damage and enhance load-bearing ability were elucidated through finite element simulations. Furthermore, this hierarchical spiderweb-like bioscaffold demonstrated favorable biological characteristics, including biocompatibility, osteogenesis, angiogenesis, and hemostasis. The presence of the nano-spiderweb structures significantly improved cell adhesion and differentiation on the scaffold and increased the spreading area of cells by 2–3 times. The dual-drug loaded bioscaffolds with full coverages of the spiderweb structure exhibited the least amount of bleeding (45.33 ± 27.47 mg) and the fastest hemostasis speed (82 ± 8.19 s) in the hemostasis test, compared to the control group. Overall, the outstanding performance makes the developed bioscaffolds a promising alternative for tissue repair and regeneration in the field of tissue engineering.

Use of acellular matrices as scaffolds in cartilage regeneration - a systematic review.

Cartilage regeneration remains a significant challenge in the field of regenerative medicine. Acellular matrix-based cartilage tissue regeneration offers an innovative approach to repairing cartilage defects by providing a scaffold for new tissue growth. Its significance lies in its potential to restore joint function, mitigate pain, and improve the quality of life for patients suffering from cartilage-related injuries and conditions. Recent advances in acellular matrix-based cartilage regeneration have focused on enhancing scaffold properties for improved cell adhesion, proliferation, and differentiation. Moreover, several scaffold techniques such as combining ADM and ACM with cartilage tissue, as well as biphasic scaffolding enjoy rising research activity. Incorporating bioactive factors and advanced manufacturing techniques holds promise for producing more biomimetic scaffolds, advancing efficient cartilage repair and regeneration. Obstacles in acellular matrix-based cartilage regeneration include achieving proper integration with surrounding tissue and ensuring long-term durability of the regenerated cartilage. Further, issues such as high costs and limited availability of suitable cells for scaffold seeding must be considered. The heterogeneity and limited regenerative capabilities of cartilage need to be addressed for successful clinical translation. Research should focus on exploring advanced biomaterials and developing new techniques, regarding easily reproductible scaffolds, ideally constructed from clinically validated and readily available commercial products. Findings underline the potential of AM-based approaches, especially rising exploration of tissue-derived ADM and ACM. In future, the primary objective should not only be the regeneration of small cartilage defects, but rather focus on fully regenerating a joint or larger cartilage defect.

Quantifying and Controlling the Proteolytic Degradation of Cell Adhesion Peptides.

Peptides are widely used within biomaterials to improve cell adhesion, incorporate bioactive ligands, and enable cell-mediated degradation of the matrix. While many of the peptides incorporated into biomaterials are intended to be present throughout the life of the material, their stability is not typically quantified during culture. In this work, we designed a series of peptide libraries containing four different N-terminal peptide functionalizations and three C-terminal functionalizations to better understand how simple modifications can be used to reduce the nonspecific degradation of peptides. We tested these libraries with three cell types commonly used in biomaterials research, including mesenchymal stem/stromal cells (hMSCs), endothelial cells, and macrophages, and quantified how these cell types nonspecifically degraded peptides as a function of terminal amino acid and chemistry. We found that peptides in solution which contained N-terminal amines were almost entirely degraded by 48 h, irrespective of the terminal amino acid, and that degradation occurred even at high peptide concentrations. Peptides with C-terminal carboxylic acids also had significant degradation when cultured with the cells. We found that simple modifications to the termini could significantly reduce or completely abolish nonspecific degradation when soluble peptides were added to cells cultured on tissue culture plastic or within hydrogel matrices, and that functionalizations which mimicked peptide conjugations to hydrogel matrices significantly slowed nonspecific degradation. We also found that there were minimal differences in peptide degradation across cell donors and that sequences mimicking different peptides commonly used to functionalize biomaterials all had significant nonspecific degradation. Finally, we saw that there was a positive trend between RGD stability and hMSC spreading within hydrogels, indicating that improving the stability of peptides within biomaterial matrices may improve the performance of engineered matrices.

Synthesis and Viscoelastic Properties of Polycaprolactone/Polyvinylidene Fluoride/Nanohydroxyapatite Composite Scaffolds

AbstractObtaining a polymer nanocomposite with optimum viscoelastic, thermal, and biocompatibility properties is the main objective when designing nanocomposite systems with potential applications in tissue engineering. For this purpose, a blend of Polycaprolactone (PCL) and Polyvinylidene fluoride (PVDF) in an 85/15 weight ratio, along with a nanocomposite reinforced by nanohydroxyapatite (nHA) particles, is fabricated using a solution casting method in a mold. The impact of nHA content on crystallinity, viscoelastic properties, thermal stability, and the properties–structure relationship of nanocomposites is evaluated using scanning electron microscopy (SEM). Dynamic mechanical thermal (DMTA) analysis is used to determine the William–Landel–Ferry (WLF) constants and the effect of nHA on the nanocomposite's viscoelastic behavior. The PCL/15PVDF/0.5 wt% nHA exhibits the maximum thermal stability (40% residual char value) and 95% increase in storage modulus at 90 °C (rubbery region) in comparison with PCL/15PVDF blend. Water contact angle (WCA) and biocompatibility tests are conducted on the PCL/15PVDF blend and nanocomposite scaffolds to design appropriate nanocomposite systems with potential applications in tissue engineering. The high hydrophilic properties are assigned to PCL/15PVDF/0.5 wt% nHA with a WCA of 67.5°. Finally, in vitro cell culture confirmed 0.5 wt% nHA significantly improves cell adhesion and cytotoxicity with MG‐63 cells.

Improved Cell Adhesion on Self-Assembled Chiral Nematic Cellulose Nanocrystal Films.

Chirality is ubiquitous in nature, and closely related to biological phenomena. Nature-originated nanomaterials such as cellulose nanocrystals (CNCs) are able to self-assemble into hierarchical chiral nematic CNC films and impart handedness to nano and micro scale. However, the effects of the chiral nematic surfaces on cell adhesion are still unknown. Herein, this work presents evidence that the left-handed self-assembled chiral nematic CNC films (L-CNC) significantly improve the adhesion of L929 fibroblasts compared to randomly arranged isotropic CNC films (I-CNC). The fluidic force microscopy-based single-cell force spectroscopy is introduced to assess the cell adhesion forces on the substrates of L-CNC and I-CNC, respectively. With this method, a maximum adhesion force of 133.2 nN is quantified for mature L929 fibroblasts after culturing for 24h on L-CNC, whereas the L929 fibroblasts exert a maximum adhesion force of 78.4 nN on I-CNC under the same condition. Moreover, the instant SCFS reveals that the integrin pathways are involved in sensing the chirality of substrate surfaces. Overall, this work offers a starting point for the regulation of cell adhesion via the self-assembled nano and micro architecture of chiral nematic CNC films, with potential practical applications in tissue engineering and regenerative medicine.

Research on 3D printed titanium alloy scaffold structure induced osteogenesis: Mechanics and in vitro testing

Several methods exist for repairing mandibular segmental bone defects, typically employing the implant method to accomplish the repair. Following a comparative analysis, the Ti6Al4V structural scaffold implant was chosen for bone defect repair. Triply periodic minimal surface (TPMS) is characterized by a high surface area to volume ratio, an average curvature of zero, and other notable advantages, providing a new line of thinking for bone tissue scaffolds. In this work, the in vitro osteogenesis of a cell unit measuring 4 mm was investigated. First, the finite element analysis (FEA) method and the mechanical experiment method were employed to screen the elasticity modulus of the cancellous bone of the mandible. Subsequently, the selective laser melting (SLM) technique was adopted to prepare three different structures precisely - Gyroid, octahedron, and cube - each with wall thicknesses of 0.3 mm, 0.4 mm, and 0.5 mm. In the in vitro osteogenic experiments, it was observed through confocal laser scanning microscopy (CLSM) that each scaffold displayed favorable cell spreading at 1 day and 3 days. Moreover, osteoblast cell adhesion and proliferation assays revealed improved cell adhesion and proliferation with prolonged co-cultivation time, signifying the excellent biocompatibility of the structural titanium alloy scaffolds. Furthermore, findings from cell differentiation and bioactivity assays indicated that the Gyroid structure exhibited superior osteogenesis compared to the cube and octahedron structures. However, no statistically significant difference was noted between varying wall thicknesses within the same structure.

Zwitterionic sulfobetaine methacrylate (SBMA) coating on hydrophobic acrylic intraocular lens material to prevent the adhesion of lens epithelial cells: Effect of SBMA concentration

Posterior capsular opacification (PCO), known as a prevalent complication of cataract surgery, occurs because of the attachment and abnormal proliferation of remaining lens epithelial cells (LECs) after cataract surgery. To reduce the PCO occurrence by improving cell adhesion resistance, we attempted zwitterionic sulfobetaine methacrylate (SBMA) coating through ultraviolet-induced graft polymerization on the surfaces of intraocular lens (IOL) materials. In this study, the effect of the concentration of SBMA monomers in the coating solutions adjusted from 10 wt% to 30 wt% was investigated on the chemical composition, morphology, and hydrophilicity of the IOL material surfaces modified with SBMA. Additionally, the effect of SBMA concentration on preventing adhesion to protein and LECs on the surfaces of SBMA-modified IOL materials was evaluated in vitro. Grafting of zwitterionic SBMA on the surfaces of hydrophobic acrylic IOL materials was confirmed by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and water contact angle (WCA). To evaluate the long-term hydrophilicity of coating films prepared with different concentrations of SBMA on the IOL material surfaces, the WCA of IOL materials stored in phosphate-buffered saline solution was measured as a function of time. The coating film prepared at a concentration of 20 wt% of SBMA showed the lowest WCA after 28 days, showing the best long-term hydrophilicity. Also, that prepared at a concentration of 20 wt% of SBMA exhibited the highest anti-adhesion effect on proteins and LECs.

Biological Surface Layer Formation on Bioceramic Particles for Protein Adsorption.

In the biomedical fields of bone regenerative therapy, the immobilization of proteins on the bioceramic particles to maintain their highly ordered structures is significantly important. In this review, we comprehensively discussed the importance of the specific surface layer, which can be called "non-apatitic layer", affecting the immobilization of proteins on particles such as hydroxyapatite and amorphous silica. It was suggested that the water molecules and ions contained in the non-apatitic layer can determine and control the protein immobilization states. In amorphous silica particles, the direct interactions between proteins and silanol groups make it difficult to immobilize the proteins and maintain their highly ordered structures. Thus, the importance of the formation of a surface layer consisting of water molecules and ions (i.e., a non-apatitic layer) on the particle surfaces for immobilizing proteins and maintaining their highly ordered structures was suggested and described. In particular, chlorine-containing amorphous silica particles were also described, which can effectively form the surface layer of protein immobilization carriers. The design of the bio-interactive and bio-compatible surfaces for protein immobilization while maintaining the highly ordered structures will improve cell adhesion and tissue formation, thereby contributing to the construction of social infrastructures to support super-aged society.

Silanization Strategies for Tailoring Peptide Functionalization on Silicon Surfaces: Implications for Enhancing Stem Cell Adhesion.

Biomaterial surface engineering and the integration of cell-adhesive ligands are crucial in biological research and biotechnological applications. The interplay between cells and their microenvironment, influenced by chemical and physical cues, impacts cellular behavior. Surface modification of biomaterials profoundly affects cellular responses, especially at the cell-surface interface. This work focuses on enhancing cellular activities through material manipulation, emphasizing silanization for further functionalization with bioactive molecules such as RGD peptides to improve cell adhesion. The grafting of three distinct silanes onto silicon wafers using both spin coating and immersion methods was investigated. This study sheds light on the effects of different alkyl chain lengths and protecting groups on cellular behavior, providing valuable insights into optimizing silane-based self-assembled monolayers (SAMs) before peptide or protein grafting for the first time. Specifically, it challenges the common use of APTES molecules in this context. These findings advance our understanding of surface modification strategies, paving the way for tailoring biomaterial surfaces to modulate the cellular behavior for diverse biotechnological applications.

Enhancing surface morphology, mechanical, and wettability properties of PVA/chitosan/HAp nanofiber scaffold through dielectric barrier discharge plasma treatment

Dielectric barrier discharge (DBD) plasma treatment has been widely used for surface functionalization, allowing for precise modification of surface chemistry and morphology. This study investigates the efficacy of DBD plasma treatment in enhancing the surface morphology and wettability of electrospun nanofiber scaffolds composed of polyvinyl alcohol (PVA), chitosan, and hydroxyapatite (HAp), with potential applications in bone tissue engineering. Scanning electron microscopy (SEM) revealed significant alterations in surface morphology after treatment, including a reduction in average fiber diameter and the presence of uneven, damaged, and even broken fibers. Interestingly, the ultimate strength of the nanofibers increased from 1.13 ± 0.05 MPa to 6.99 ± 0.07 MPa despite the decrease in diameter. Contact angle measurements confirmed a remarkable improvement in wettability, with the contact angle decreasing from 39.46° to 7.45° following increasing treatment time. This enhanced wettability suggests improved cell adhesion, potentially leading to more effective bone tissue regeneration.

Influence of micro and nanoporous TiO2 surface modifications on physical-chemical and biological interactions

Titanium is widely used in implants but can cause adverse reactions like inflammation and tissue rejection. Surface modifications like acid-etching and anodization improve implant properties and osseointegration. This study investigated how micro and nanoporous TiO2 films affect the implant-host interaction, focusing on physical–chemical and biological aspects. Surface treated implants were obtained by acid-etched and anodization of commercially pure titanium (CPTi). Samples were characterized by FE- and FIB-SEM, XRD, EDX, WCA, profilometry, and electrochemical behavior was also investigated. Biocompatibility was accessed by protein adsorption (albumin and serum proteins), hemolysis, and in vitro fibroblast interaction. Anodic samples exhibited the highest corrosion resistance and apatite deposition. Protein adsorption was related to surface roughness and wettability. Samples followed the Langmuir model isotherm (Type I), except for galvanostatic samples (Type III isotherm). Kinetic adsorption was modeled by a pseudo-first-order model, wherein rate-limiting step is albumin diffusion into pores. All surfaces met the hemocompatibility requirements for its use as biomaterial (hemolysis index < 2 %). The upper surface roughness threshold was identified at approximately Sa ≈ 1 µm for better fibroblast viability, adhesion, and proliferation. Combining the results, nanoporous samples present optimized surface conditions that enhance body-fluid contact and improve cell adhesion, thereby contributing to long-term stability.

Biocompatability chitosan /Aloe barbadensis miller loaded moxifloxacin composite film: A multifunctional bio-platform for the treatment of breast cancer

Binary biodegradable polymers exhibit excellent functional behavior but the limited mechanical integrity for regulating drug release within the polymeric matrix, hence it needs modification in the polymer network to overcome the limitations. The compatibility of bipolymer blends with incorporation of drugs within their matrices to enhance physicochemical properties and drug delivery kinetics have garnered significant attention in recent research. Herein, we examine the influence of the film produced by the casting technique, which consists of chitosan (CS) and Aloe barbadensis miller (ABM) gel, embedded with moxifloxacin (MoF), on attenuating the breast cancer (MCF-7) cell line. Firstly, spectroscopy confirmed the intermolecular interactions between the matrixes and the grafting of components. Notably, the addition of ABM produces significant changes in the film properties, such as decreased elongation. The pivotal moment resulted in the generation of more stable films that displayed enhanced stability at temperatures below 200 °C, as confirmed by TGA analysis. Additionally, film surfaces exhibiting strong water affinity were found to be more favorable for cell adhesion, subsequently hindering the proliferation of compromised cells. Remarkably, the In vitro cytotoxicity study showed the antibiotic-grafted CS-ABM/MoF scaffolds exhibited high cell adhesion and improved the rate of cell death was higher compared to other films. The antibacterial activity against S. aureus and E. coli results strongly suggests the enhanced antibiotic ability of the polymeric CS- ABM/MoF film. These results findings indicated that the CS- ABM/MoF scaffolds' hydrophilic surface significantly contributes to the improved cell adhesion efficiently used for biomedical applications.

Preparing gelatin-containing polycaprolactone / polylactic acid nanofibrous membranes for periodontal tissue regeneration using side-by-side electrospinning technology.

Electrospinning technology has recently attracted increased attention in the biomedical field, and preparing various cellulose nanofibril membranes for periodontal tissue regeneration has unique advantages. However, the characteristics of using a single material tend to make it challenging to satisfy the requirements for a periodontal barrier film, and the production of composite fibrous membranes frequently impacts the quality of the final fiber membrane due to the influence of miscibility between different materials. In this study, nanofibrous membranes composed of polylactic acid (PLA) and polycaprolactone (PCL) fibers were fabricated using side-by-side electrospinning. Different concentrations of gelatin were added to the fiber membranes to improve their hydrophilic properties. The morphological structure of the different films as well as their composition, wettability and mechanical characteristics were examined. The results show that PCL/PLA dual-fibrous composite membranes with an appropriate amount of gelatin ensures sufficient mechanical strength while obtaining improved hydrophilic properties. The viability of L929 fibroblasts was evaluated using CCK-8 assays, and cell adhesion on the scaffolds was confirmed by scanning electron microscopy and by immunofluorescence assays. The results demonstrated that none of the fibrous membranes were toxic to cells and the addition of gelatin improved cell adhesion to those membranes. Based on our findings, adding 30% gelatin to the membrane may be the most appropriate content for periodontal tissue regeneration, considering the scaffold's mechanical qualities, hydrophilic properties and biocompatibility. In addition, the PCL-gelatin/PLA-gelatin dual-fibrous membranes prepared using side-by-side electrospinning technology have potential applications for tissue engineering.

Biomedical Efficacy of Garlic‐Extract‐Loaded Core‐Sheath Plasters for Natural Antimicrobial Wound Care

AbstractThis work explores the application of Allium sativum (Garlic) extract, in the creation of novel polymeric core‐sheath fibers for wound therapy applications. The core‐sheath pressurized gyration (CS PG) technology is utilized to mass‐produce fibers with a polycaprolactone (PCL) core and a polyethylene oxide (PEO) sheath, loaded with garlic extract. The produced fibers maintain structural integrity, long‐term stability and provide a cell‐friendly surface with rapid antibacterial activity. The physical properties, morphology, therapeutic delivery, cytotoxicity, thermal and chemical stability of PCL, PEO, PEO/Garlic, Core‐Sheath (CS) PEO/PCL and PEO/Garlic/PCL fibers are analyzed. Findings show that the addition of garlic extract greatly increases the fibers’ thermal durability, while decreasing their diameter, thus improving cell adhesion and proliferation. In‐vitro release tests reveal a rapid release of garlic extract, which has significant antibacterial action against both Gram‐negative Escherichia coli (E. coli) and Gram‐positive Staphylococcus aureus (S. aureus) bacteria species. Cell viability experiments validate the fiber samples' biocompatibility and nontoxicity, making them appropriate for integrative medicine applications. These core‐sheath structures emphasize the potential of combining natural therapeutic agents with advanced material technologies to develop cost‐effective, sustainable and highly effective wound dressings, offering a promising solution to the growing concerns associated with conventional synthetic antibacterial agents.

Conductive and Enhanced Mechanical Strength of Mo2Ti2C3 MXene-Based Hydrogel Promotes Neurogenesis and Bone Regeneration in Bone Defect Repair.

Bone defects are common with increasing high-energy fractures, tumor bone invasion, and implantation revision surgery. Bone is an electroactive tissue that has electromechanical interaction with collogen, osteoblasts, and osteoclasts. Hydrogel provides morphological plasticity and extracellular matrix (ECM) 3D structures for cell survival, and is widely used as a bone engineering material. However, the hydrogels have poor mechanical intensity and lack of cell adhesion, slow gelation time, and limited conductivity. MXenes are novel nanomaterials with hydrophilic groups that sense cell electrophysiology and improve hydrogel electric conductivity. Herein, gelatin had multiple active groups (NH2, OH, and COOH) and an accelerated gelation time. Acrylamide has Schiff base bonds to cross-link with gelatin and absorb metal ions. Deacetylated chitosan improved cell adhesion and active groups to connect MXene and acrylamide. We constructed Mo2Ti2C3 MXene hydrogel with improved elastic modulus and viscosity, chemical cross-linking structure, electric conductivity, and good compatibility. Mo2Ti2C3 MXene hydrogel exhibits outstanding osteogenesis in vitro. Mo2Ti2C3 MXene hydrogel promotes osteogenesis via alkaline phosphatase (ALP) and alizarin red S (ARS) staining, improving osteogenic marker genes and protein expressions in vitro. Mo2Ti2C3 MXene hydrogel aids new bone formation in the in vivo calvarial bone defect model via micro-CT and histology. Mo2Ti2C3 MXene hydrogel facilitates neurogenesis factors nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) expression, and aids newly born neuron marker Tuj-1 and sensory neuron marker serotonin (5-HT) and osteogenesis pathway proteins, runt-related transcription factor 2 (Runx2), osteocalcin (OCN), SMAD family member 4 (SMAD4), and bone morphogenetic protein-2 (BMP2) in the bone defect repair process. Mo2Ti2C3 MXene hydrogel promotes osteogenesis and neurogenesis, which extends its biomedical application in bone defect reconstruction.