Scaffolds For Tissue Engineering Research Articles

Inorganic-Based Nanoparticles and Biomaterials as Biocompatible Scaffolds for Regenerative Medicine and Tissue Engineering: Current Advances and Trends of Development

Regenerative medicine amalgamates stem cell technology and tissue engineering strategies to replace tissues and organs damaged by injury, aging, ailment, and/or chronic conditions by leveraging the innate self-healing mechanism of the body. The term ‘regenerative medicine’ was coined by William A. Haseltine during a 1999 conference on Lake Como. Since its inception in 1968, the field has offered clinical benefits for the regeneration, repair, and restoration of bones, skin, cartilage, neural tissue, and the heart, as well as scaffold fabrication. The field of tissue engineering and regenerative medicine can vastly benefit from advancements in nanoscience and technology, particularly in the fabrication and application of inorganic-based nanoparticles and bionanomaterials. Due to the tunable intrinsic properties, i.e., size, topography, surface charge, and chemical stability, inorganic-based nanoparticles and biomaterials have surpassed traditional synthetic materials. Given the wide gamut of near-future applications of inorganic nanoparticles and biomaterials, this article gives an overview of the emerging roles in stem cell regenerative research, tissue engineering, artificial skin and cartilage regeneration, neural nerve injuries, 3D bioprinting, and development of new inorganic bio-scaffolds. The review also addresses the challenges related to the clinical application and tissue compatibility of inorganic nanoparticles and biomaterials, utilizing current state-of-the-art techniques.

Application of Polylactic Acid in Clinical Medicine

Polylactic acid (PLA), a bio-based and biodegradable material, shows significant potential in environmental protection and clinical medicine. Derived from renewable resources, PLA's biodegradability reduces long-term environmental pollution by allowing it to decompose rapidly under specific conditions. This review explores PLA's applications in clinical medicine, emphasizing its mechanical properties, biocompatibility, and controlled degradation rates. The study covers PLA's extensive use in drug delivery systems, absorbable sutures, and tissue engineering scaffolds, highlighting its compatibility with human tissues and low immunogenicity. Research methods and designs, including in vitro and in vivo experiments, are discussed to evaluate PLA's efficacy and safety. The challenges of high production costs and specific degradation conditions are also addressed. Future research directions include developing new catalysts to improve synthesis efficiency and exploring renewable raw materials to reduce costs and environmental impact. As global awareness of sustainable development grows, the demand for PLA and other degradable plastics is expected to increase, expanding their applications in various fields. In conclusion, PLA offers substantial advantages in reducing reliance on fossil fuels and mitigating environmental pollution, while providing innovative solutions in the medical field. Technological advancements and increased production are anticipated to lower costs, making PLA more economically competitive and accelerating its application in both environmental protection and clinical medicine.

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

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

Biowaste Transformation to Functional Materials: Structural Properties, Extraction Methods, Applications, and Challenges of Silk Sericin

AbstractThis review underscores the novelty of silk sericin, often regarded as a byproduct in silk production. Comprising approximately 30% of silk, sericin possesses valuable properties that have been largely overlooked in favor of silk fibroin. This work focuses on innovative extraction methods to convert sericin, typically considered waste, into a valuable resource. By examining these extraction techniques alongside diverse applications, the review aims to enhance the recognition and utilization of silk sericin in research and industry. Various extraction processes where the traditional methods, and some new techniques, are all discussed. In detail, the advantages, limitations, and strategy optimization associated with each extraction method are highlighted. For instance, silk sericin has shown promise as a wound treatment agent, a scaffold for tissue engineering, a carrier for drug delivery, and a biomaterial for regenerative medicine in the field of biomedical science due to its biocompatibility, biodegradability, and nontoxicity. Additionally, it also finds application in the cosmetic industry, where it is used in skincare products due to its moisturizing, antioxidant, and antiaging properties. Eventually, the challenges, limitations, and prospects of silk sericin are intensively discussed. This comprehensive review is expected to serve the growing body of knowledge surrounding silk sericin and foster further research and development of silk sericin‐related fields.

Tailoring the mechanical properties of macro-porous PVA hydrogels for biomedical applications

Polyvinyl alcohol (PVA) is a biocompatible biopolymer with superior dimensional and mechanical stability when compared to naturally available biomaterials such as collagen and gelatin. Furthermore, PVA in hydrogel form behaves non-linearly during mechanical loading, generating a response like soft biological tissues. Generally, PVA hydrogels are fabricated using freeze-thaw cycles (FTCs) and changing the number of FTCs gives control over its mechanical properties. Porosity of the hydrogel is another important factor which determines its mechanical properties and is also evident in biological soft tissues. Incorporating macro-pores in PVA hydrogels substantially reduces the stiffness of the material and can mimic some porous tissues such as lung, liver, bone marrow, kidneys, urethra and penile tissues (corpus cavernosa). Within this study, we developed macro-porous PVA hydrogels using the freeze-thaw process followed by particulate leaching of sacrificial 3D-printed and milled PVA (m-PVA) filler particles. This fabrication method enables control over the porosity in macro-porous PVA hydrogels, which is crucial not only for tuning mechanical properties but also for mimicking the structure of spongy tissues, such as liver tissue and corpus cavernosum in the penile tissue, for example. We investigated the level of porosity in the specimen using optical microscopy to understand the distribution of the pores and the pore size. The tunability of the mechanical properties of PVA hydrogels is, a key finding of this study and is achieved using three factors: (i) weight percentage of sacrificial fillers, (ii) number of FTCs and (iii) concentration of PVA. These macro-porous PVA specimens have wide ranging biomedical applications as biological soft tissue analogues, or tissue engineering scaffolds, where the PVA hydrogel can be tuned to match the mechanical properties of these soft biological tissues.

Investigation of Elaeocarpus ganitrus seed (EGs) powder as a sustainable composite biomaterial: Effects of particle size on the mechanical, frictional, and thermal properties for potential biomedical applications

This study explores the potential of Elaeocarpus ganitrus seed (EGs) powder as a sustainable composite biomaterial, focusing on its particle size effects on the mechanical, frictional, and thermal properties of composite materials for potential biomedical applications such as prosthetics and implants. Composite specimens were produced using the compression hot molding method, utilizing EG powder particles of varying sizes (120, 140, and 200-mesh sieving). The influence of EG powder particle size on key properties was systematically investigated. The findings reveal that reducing the particle size of EGs leads to a decrease in density and hardness of the composite, with the largest particle size (BP1) resulting in the highest density and hardness. Friction coefficient measurements indicated suitability for biomedical applications where surface interaction and wear resistance are critical, such as joint prosthetics. Thermal analysis showed that BP1 exhibited superior thermal stability, with a maximum decomposition temperature (Tmax) exceeding 375 °C. Differential scanning calorimetry identified significant differences in glass transition temperature (Tg) and crystallization temperature (Tc) across specimens. The composites demonstrated exceptional thermal performance, surpassing previous benchmarks for biomaterials in high-temperature environments. The mechanical and thermal characteristics of Specimen BP1—2.725 g/cm3 density, 74 Shore D hardness, 0.159 coefficient of friction, 93.3% total residual, 378.14 °C Tmax, 426.25 °C Tc, and 376.87 °C Tg—suggest its potential for biomedical applications requiring durability and thermal resilience, such as in orthopedic devices and tissue engineering scaffolds.

Identification of a Regenerative Protocol for Recellularizing Human Auricular Cartilage Scaffolds.

Utilizing biological scaffolds for cartilage tissue engineering is a promising tool for improving auricular reconstruction. Decellularized auricular scaffolds provide a means of regenerating cartilage for in vivo implantation, but identifying the ideal regenerative mix remains challenging. Human cadaver auricular cartilage was decellularized and recellularized with either auricular chondrocytes alone, auricular chondrocytes with adipose-derived stem cells, or both cells with platelet-rich plasma. Confirmation of decellularization and recellularization was done by hematoxylin and eosin staining. Extracellular matrix preservation and production were determined by Masson's trichrome, Alcian blue, and Verhoeff-van Gieson staining. Collagen II assessments were made using immunohistochemistry. Decellularization of cadaver auricular cartilage was confirmed by the absence of cells, reduction in glycosaminoglycans, and the preservation of collagen and elastin. Recellularization was more efficient when chondrocytes were seeded with adipose-derived stem cells, which was enhanced by adding platelet-rich plasma. Coculture with platelet-rich plasma yielded better total collagen (56% increase) and glycosaminoglycan (47% increase) induction. Moreover, when platelet-rich plasma was added, collagen II induction was significantly increased (42%; P < 0.05). We identified a regenerative protocol that included auricular chondrocytes, adipose-derived stem cells, and platelet-rich plasma, which stimulated chondrogenesis on decellularized auricular cartilage. This finding provides a model to explore cartilage formation and the potential for improving auricular and cartilage-based reconstruction.

Construction of Aligned Polycaprolactone/Poly(Glycerol Sebacate)/Polysulfone Nanofibrous Scaffolds for Tissue Engineering of the Ventricularis Layer of Heart Valves

Construction of Aligned Polycaprolactone/Poly(Glycerol Sebacate)/Polysulfone Nanofibrous Scaffolds for Tissue Engineering of the Ventricularis Layer of Heart Valves

A drug-loaded nano chitosan/hyaluronic acid hydrogel system as a cartilage tissue engineering scaffold for drug delivery

Cartilage lesions, especially osteoarthritis (OA), usually arise from aging, trauma, or obesity and require medical intervention due to the damaged site's inflammation and the cartilage tissue's poor self-healing capacity. This study aimed to prepare a drug-loaded nanoparticle hydrogel system with anti-inflammatory and chondroprotective effects to treat OA. First, hyaluronic acid (HA) was oxidized to create aldehyde functional groups and then cross-linked with adipic acid dihydrazide (ADH) to form a hydrogel. Next, chitosan nanoparticles (CS NPs) loaded with an anti-inflammatory molecule (fisetin) and or a chondrogenic and chondroprotective agent (kartogenin) were incorporated into the hyaluronan hydrogel to improve the release profile of the drug and increase its retention time in the joint cavity. Incorporating drug-loaded NPs into the hyaluronan hydrogel provided the hydrogel with controlled release features and improved properties. In addition, the real-time PCR (Polymerase chain reaction) results showed that the hyaluronan hydrogel containing both drug-loaded NPs performed better than either constituent alone on an in vitro model of OA. Finally, based on the results of in vitro evaluation, this drug-loaded nanoparticle hydrogel system can be a promising technique for treating OA by rapidly suppressing inflammation and supporting cartilage regeneration and requires further investigation in an animal model of OA. Meanwhile, this study investigated, for the first time, the effect of the simultaneous use of fisetin and kartogenin together with a nano CS/HA hydrogel system to treat OA.

Electrospun Polylactic Acid/Polyethylene Glycol/ Silicate‐Chlorinated Bioactive Glass Composite Scaffolds for Potential Bone Regeneration

ABSTRACTThe integration of bioglass with polymers in tissue engineering scaffolds holds promise for enhancing bone regeneration. This study explores the fabrication and characterization of composite scaffolds comprising polylactic acid (PLA)/polyethylene glycol (PEG) fibers incorporated with silicate‐chlorinated bioglasses (45S5 and 58S). Electrospinning was utilized to produce the scaffolds, followed by physical–chemical and in vitro evaluations. Scanning electron microscopy (SEM) revealed uniform fiber formation, with bioglass incorporation observed in the composite groups. Bioglass incorporation led to a significant reduction in fiber diameter. Thermogravimetric analysis (TGA) estimated bioglass content, with 58S exhibiting the highest incorporation. Contact angle measurements indicated enhanced hydrophilicity in bioglass‐containing groups. In vitro, bioactivity assessment in simulated body fluid (SBF) demonstrated apatite formation potential and the pH variance indicates a slightly alkaline to neutral condition. Cell culture studies revealed robust cellular adhesion and metabolic activity across all groups, with no cytotoxic effects observed. Overall, these findings suggest the potential of PLA/PEG bioglass composite scaffolds for bone tissue engineering applications.

Implementing Chicken Chorioallantoic Membrane (CAM) Assays for Validating Biomaterials in Tissue Engineering: Rationale and Methods.

Tissue engineering is a promising approach for generating or repairing living tissues. The development of innovative biomaterials for tissue engineering has the potential to address the unmet clinical needs in certain applications. However, before these biomaterials can be used in clinical settings, they must undergo preclinical testing to ensure safety and performance. The chicken chorioallantoic membrane (CAM) assay is a preferred screening tool for studying biocompatibility, angiogenesis, and inflammation induced by biomaterials owing to ethical and economic considerations. This CAM-based platform increased the throughput of biomaterial testing for tissue engineering before invivo testing. In this paper, we discuss the advantages of the CAM model. We also provided a step-by-step guide for implementing the CAM model in a research laboratory, along with tips and tricks for successfully running CAM assays. Finally, we present examples of biomaterials screened using CAM assays. CAM assay is a powerful invivo model for assessing the angiogenic potential of tissue-engineered scaffolds. This guide provides a framework for conducting the assay, but specific experimental conditions should be optimized based on the scaffold material and the research question.

Experimental evaluation and simulation of myoblast cell alignment on the UV-irradiated liquid crystalline elastomers as a versatile tissue-engineered Scaffolding material

Efforts to develop versatile tissue-engineered scaffolds mimicking the functions of extracellular matrices (ECMs) have led to the emergence of liquid crystalline elastomers (LCEs) as promising materials. Here, thiol-acrylate-based LCEs forming a nematic phase upon UV irradiation were synthesized, and their biological compatibility was evaluated using C2C12 myoblast cells. Prior to UV exposure, some characteristics, e.g., phase transition temperature (TNI), order parameter, and reaction time, of the as-synthesized LCEs are characterized for property optimization. Fourier-transform infrared spectroscopy revealed that thiol-acrylate Michael addition polymerization was successful, judged by the disappearance of the characteristic peaks of thiol and acrylate groups. Differential scanning calorimetry thermograms and dynamic mechanical thermal analysis curves showed TNI values at ca. 49 °C, at which point the nematic phase is the dominant morphology. Moreover, the cross-linking density, the fixing, and the recovery ratios for the sample with optimal properties (i.e., LCE3) were determined to be 10.3 mol/cm3, 97.2 % and 91 %, respectively. Assessment of mesomorphism and roughness demonstrated the suitability of LCE3 for cell culture. Subsequent studies on adhesion, viability, differentiation, and proliferation of cultured myoblast cells, coupled with particle image velocimetry simulation, highlighted the potential of UV-irradiated LCE3 as a promising scaffold material for inducing surface morphology-induced cellular alignment and interactions.

Construction and performance evaluation of fully biomimetic hyaline cartilage matrix scaffolds for joint defect regeneration

Due to the absence of nerves and blood vessels in articular cartilage, its regeneration and repair present a significant and complex challenge in osteoarthritis treatment. Developing a specialized physical and chemical microenvironment supporting cell growth has been difficult in cartilage grafting, especially when aiming for comprehensive biomimetic solutions. Based on previous research, we have designed a tissue-engineered decellularized living hyaline cartilage graft (dLhCG). The study developed a method to improve the hydrophilicity and stiffness of scaffolds by employing chemical grafting techniques and designed a decellularized hyaline cartilage phenotype matrix scaffold for tissue engineering. Here, we reported a method using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride /N-hydroxysuccinimide (EDC/NHS) to achieve the grafting of chondroitin sulfate (CS) onto dLhCG, ultimately producing a tissue-engineered hyaline cartilage graft with the CS (dLhCG/CS). Young's modulus measurements revealed that the cross-linked scaffolds exhibited enhanced mechanical properties. We implanted the cross-linked dLhCG/CS scaffolds into the trochlear region of rat joints and evaluated their functionality through histological analysis and biomechanical tests. After 12 weeks, the dLhCG/CS scaffolds demonstrated excellent bioinductive activity comparable to dLhCG. The regenerated tissue effectively maintained a hyaline cartilage phenotype and exhibited similar mechanical properties, playing a crucial role in cartilage regeneration.

Integrated environmental and health economic assessments of novel xeno-keratografts addressing a growing public health crisis

Tissue scarcity poses global challenges for corneal transplantation and public health. Xeno-keratoplasty using animal-derived tissues offers a potential solution, but its environmental and economic implications remain unclear. This study evaluated two xeno-keratoplasty procedures at a single institution: (1) native corneas (Option 1) and (2) tissue-engineered corneal scaffolds derived from slaughterhouse waste (Option 2). Life cycle assessment (LCA) quantified environmental impacts across 18 midpoint indicators, while cost-effectiveness analysis (CEA) incorporated cost and environmental impact using two approaches. Option 1 exhibited significantly lower environmental impact than Option 2 across most indicators, primarily due to the energy and equipment demands of cell culture in Option 2. Both CEA approaches (carbon offset pricing and utility decrement) demonstrated cost-effectiveness dominance for Option 1. Xeno-keratoplasty using native corneas (Option 1) appears more environmentally and economically favorable than tissue-engineered scaffolds (Option 2) in the current analysis. Future studies could explore diverse xeno-keratoplasty techniques for optimizing sustainability.

Poly(HEMA-co-MMA) Hydrogel Scaffold for Tissue Engineering with Controllable Morphology and Mechanical Properties Through Self-Assembly

Poly(2-hydroxyethyl methacrylate) (PHEMA) has been widely used in medical materials for several decades. However, the poor mechanical properties of this material have limited its application in the field of tissue engineering. The purpose of this study was to fabricate a scaffold with suitable mechanical properties and in vitro cell responses for soft tissue by using poly(HEMA-co-MMA) with various concentration ratios of hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA). To customize the concentration ratio of HEMA and MMA, the characteristics of the fabricated scaffold with various concentration ratios were investigated through structural morphology, FT-IR, mechanical property, and contact angle analyses. Moreover, in vitro cell responses were observed according to the various concentration ratios of HEMA and MMA. Consequently, various morphologies and pore sizes were observed by changing the HEMA and MMA ratio. The mechanical properties and contact angle of the fabricated scaffolds were measured according to the HEMA and MMA concentration ratio. The results were as follows: compressive maximum stress: 254.24–932.42 KPa; tensile maximum stress: 4.37–30.64 KPa; compressive modulus: 16.14–38.80 KPa; tensile modulus: 0.5–2 KPa; and contact angle: 36.89–74.74°. In terms of the in vitro cell response, the suitable cell adhesion and proliferation of human dermal fibroblast (HDF) cells were observed in the whole scaffold. Therefore, a synthetic hydrogel scaffold with enhanced mechanical properties and suitable fibroblast cell responses could be easily fabricated for use with soft tissue using a specific HEMA and MMA concentration ratio.

A facile method for carbon nanotube/carbon fiber‐reinforced polylactic acid composites

AbstractThe mechanical strength of polylactic acid (PLA) can be improved by carbon fiber (CF) compositing to expand its application in tissue engineering scaffolds. However, the mechanical strength of CF‐reinforced polylactic acid (CFRPLA) composites is compromised due to weak interfacial interaction resulting from the chemically inert surface of CF. In the article, carbon nanotube (CNT) with poly(diallyldimethylammonium chloride) (PDDA) as a coupling agent was covered on CF to improve the chemical activity and roughness of the surface of CF, and then the as‐prepared CF‐PCNT were further incorporated into PLA via melt compounding. The yield strength, modulus, and thermal conductivity of PLA/CF‐PCNT were 14.09%, 7.65%, and 5.24% higher than those of PLA/CF, respectively, and the volume resistivity was 99.74% lower at a 10 wt% loading. The enhancement for the mechanical properties of PLA/CF‐PCNT composites could be ascribed to the mechanical locking, hydrogen bonds and covalent bonds between CF and matrix through the interface modulation of CNT and PDDA. This facile and non‐destructive method offers a novel strategy for the modification of CF fillers.Highlights CF was modified by PDDA and CNT through a facile and non‐destructive method. The active functional groups and roughness on the surface of CF were increased. The surfaces of CFs were characterized by FT‐IR, Raman spectra, XPS and SEM. The interface was improved by mechanical locking, covalent, and hydrogen bonds. The mechanical strength, electrical and thermal conductivity of composites were improved.

Human amniotic membrane scaffold enhances adipose mesenchymal stromal cell mitochondrial bioenergetics promoting their regenerative capacities.

The human amniotic membrane (hAM) has been applied as a scaffold in tissue engineering to sustain stem cells and enhance their regenerative capacities. We investigated the molecular and biochemical regulations of mesenchymal stromal cells (MSCs) cultured on hAM scaffold in a three-dimensional (3D) setting. Culture of adipose-MSCs (AMSCs) on decellularized hAM showed significant improvement in their viability, proliferative capacity, resistance to apoptosis, and enhanced MSC markers expression. These cultured MSCs displayed altered expression of markers associated with pro-angiogenesis and inflammation and demonstrated increased potential for differentiation into adipogenic and osteogenic lineages. The hAM scaffold modulated cellular respiration by upregulating glycolysis in MSCs as evidenced by increased glucose consumption, cellular pyruvate and lactate production, and upregulation of glycolysis markers. These metabolic changes modulated mitochondrial oxidative phosphorylation (OXPHOS) and altered the production of reactive oxygen species (ROS), expression of OXPHOS markers, and total antioxidant capacity. They also significantly boosted the urea cycle and altered the mitochondrial ultrastructure. Similar findings were observed in bone marrow-derived MSCs (BMSCs). Live cell imaging of BMSCs cultured in the same 3D environment revealed dynamic changes in cellular activity and interactions with its niche. These findings provide evidence for the favorable properties of hAM as a biomimetic scaffold for enhancing the in vitro functionality of MSCs and supporting their potential usefulness in clinical applications.

The induction of bone formation by 3D-printed PLGA microsphere scaffolds in a calvarial orthotopic mouse model: a pilot study

Polymeric biodegradable microspheres are readily utilized to support targeted drug delivery for various diseases clinically. 3D printed tissue engineering scaffolds from polymer filaments with embedded microspheres or nanoparticles, as well as bulk microsphere scaffolds, have been investigated for regenerative medicine and tissue engineering. However, 3D printed scaffolds consisting only of a homogenous microsphere size with an optimized architecture that includes a unique micro- and macroporosity, have been challenging to produce and hence, have not been assessed in the literature yet. Utilizing our recently established 3D-MultiCompositional Microsphere-Adaptive Printing (3D-McMap) method, the present study evaluated the effectiveness of 3D-printed poly (lactic-co-glycolic acid) (PLGA) microsphere scaffolds, consisting of microsphere sizes 50, 100, or 200 μm, on the induction of bone formation when implanted in the calvarial murine regeneration model. Our results showed that PLGA microsphere scaffolds possess unique properties that support bone regeneration by supporting osteoconduction and stimulating, in our opinion, true spontaneous osteoinduction. The study demonstrated that PLGA microsphere-based scaffolds support bone growth in the absence of additional growth factors and promote osteogenesis primarily via their unique geometric configuration. The larger the microspheres were, the greater de novo bone formation was. This proves that bone tissue engineering scaffolds 3D printed from microspheres, enabled by the 3D-McMap method, are superior over bulk material printed scaffolds, as they possess the unique capability of spontaneous induction of new bone formation. With the addition of encapsulated modulatory bone-forming biomolecules they can substantially improve the spatiotemporal control of tissue morphogenesis, potentially leading to new innovative clinical tissue repair therapies that regenerate bone in large defects correctly and fully.

Enhanced Mechanical Properties and Degradation Control of Poly(Lactic) Acid/Hydroxyapatite/Reduced Graphene Oxide Composites for Advanced Bone Tissue Engineering Application

This study explores the enhancement of poly(lactic acid) (PLA) matrix using calcium hydroxyapatite (cHAP) and reduced graphene oxide (rGO) for developing composite scaffolds aimed at bone regeneration applications. The PLA composites were fabricated through solvent evaporation and melt extrusion and characterized by various techniques, including thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and mechanical testing. The incorporation of cHAP and rGO significantly improved the thermal, mechanical, and morphological properties of the PLA matrix. Mechanical testing revealed that adding 10% cHAP and varying amounts of rGO (0.1%, 0.3%, 0.5%) enhanced tensile and compressive strengths, with the highest improvements observed at 0.5% rGO content. Thermal analysis showed increased thermal stability with higher degradation temperatures for the composites. Spectroscopic analyses confirmed the effective integration of cHAP and rGO into the PLA matrix with characteristic peaks of the fillers identified in the composite spectra. In vitro, degraded action tests in phosphate-buffered saline (PBS) at pH 7.4 over 12 months indicated that composites with higher rGO content exhibited lower mass loss and better mechanical stability. Furthermore, finite element analysis (FEA) simulations were performed to validate the experimental results, demonstrating a strong correlation between simulated and experimental compressive strengths. This novel approach demonstrates the potential of PLA/cHAP/rGO composites in creating effective and biocompatible scaffolds for tissue engineering, providing a comprehensive analysis of the synergistic effects of cHAP and rGO on the PLA matrix and offering a promising material for bone regeneration applications.

Double-Network Hydrogel 3D BioPrinting Biocompatible with Fibroblast Cells for Tissue Engineering Applications

The present study examines the formulation of a biocompatible hydrogel bioink for 3D bioprinting, integrating poly(ethylene glycol) diacrylate (PEGDA) and sodium alginate (SA) using a double-network approach. These materials were chosen for their synergistic qualities, with PEGDA contributing to mechanical integrity and SA ensuring biocompatibility. Fibroblast cells were included in the bioink and printed with a Reg4Life bioprinter employing micro-extrusion technology. The optimisation of printing parameters included needle size and flow velocities. This led to precise structure development and yielded results with a negligible deviation in printed angles and better control of line widths. The rheological characteristics of the bioink were evaluated, demonstrating appropriate viscosity and shear-thinning behaviour for efficient extrusion. The mechanical characterisation revealed an average compressive modulus of 0.38 MPa, suitable for tissue engineering applications. The printability of the bioink was further confirmed through the evaluations of morphology and diffusion rates, confirming structural integrity. Biocompatibility assessments demonstrated a high cell viability rate of 82.65% following 48 h of incubation, supporting the bioink’s suitability for facilitating cell survival. This study introduced a reliable technique for producing tissue-engineered scaffolds that exhibit outstanding mechanical characteristics and cell viability, highlighting the promise of PEGDA–SA hydrogels in bioprinting applications.