Search Results (2,981)

Objectives: Autologous bone grafting remains the gold standard for maxillofacial reconstruction but is limited by tissue scarcity and donor-site morbidity. Consequently, substitutes like bioactive glass (BG), beta-tricalcium phosphate (β-TCP), and deproteinized bovine bone (DBB) are widely used. However, comprehensive mechanistic comparisons among them remain scarce. Materials and Methods: We systematically evaluated these substitutes under standardized in vitro conditions to compare their physicochemical transformations, degradation profiles, biological performances, and underlying osteogenic molecular pathways. Results: In simulated body fluid, BG underwent rapid hydroxyapatite mineralization, whereas the highly porous DBB and dense β-TCP remained structurally inert. Degradation assays revealed BG exhibited the fastest mass loss and ion release, β-TCP showed intermediate degradation, and DBB maintained high in vitro structural stability. Biologically, all materials showed favorable cytocompatibility and comparable angiogenic potential. However, BG demonstrated significant antibacterial activity (E. coli, S. aureus) and a strong potential to enhance osteogenic differentiation, significantly upregulating the protein-level expression of RUNX2 and OCN, alongside the transcriptional upregulation of Bmp2, Runx2, and Ocn. Transcriptomic profiling and pharmacological validation suggest that the enhanced osteogenic performance of BG might be associated with specific regulatory pathways, supporting the hypothesis that the suppression of NF-κB-mediated inflammation and the activation of the ECM-Integrin-FAK mechanotransduction axis play potential roles. Conclusions: BG offers high bioactivity and notable potential to enhance osteogenic differentiation in vitro but degrades rapidly. DBB ensures structural durability without intrinsic osteoinductivity, and β-TCP provides a balanced, intermediate profile. These in vitro mechanistic insights provide a theoretical foundation for future in vivo evaluations and designing next-generation bone scaffolds. Full article

The surgical management of distal tibia fractures in the elderly is increasingly complex due to the rising prevalence of osteoporosis and the unique anatomical constraints of the region. While autologous bone graft remains the gold standard, its limitations have led to the widespread adoption of synthetic and biological substitutes. This narrative review explores the current trends in bone grafting for osteoporotic distal tibia fractures, focusing on pure β-tricalcium phosphate (β-TCP) and demineralized bone matrix (DBM). We specifically examine the biological mechanisms, resorption kinetics, and clinical outcomes of these materials. Furthermore, we highlight the emerging clinical preference for powder-type pure β-TCP (Neobone™) due to its superior surface area and packing efficiency in irregular metaphyseal voids. Powder-type pure β-TCP demonstrates superior packing efficiency and predictable resorption kinetics for metaphyseal void filling, while DBM remains a context-dependent biological supplement. Ion-substituted TCP formulations, pharmacological augmentation, and hybrid scaffolds are highlighted as future directions. Full article

The development of biocompatible materials has gained traction due to the increasing clinical demands for customizable and functional medical devices. Chitosan, a deacetylated derivative of chitin, is a naturally occurring biopolymer with strong antimicrobial properties, immunocompatibility, and structural adaptability, making it a promising candidate for biomedical applications. Through mechanisms such as crosslinking, ionic bonding, gas formation, and UV radiation, the mechanical properties and stimulus responses of chitosan-based hydrogels can be tailored for drug delivery at specific sites or under specific pH, light, or electrical conditions. Beyond drug delivery, chitosan hydrogels have shown considerable potential for vascular tissue repair. The porous structure of chitosan allows patient specific vascular scaffolding to be created that promotes the recovery rate veins and stenting procedures. Thermally sensitive hydrogels can deliver drugs to target regions to further assist in vascular healing. Furthermore, recent developments with composite polymers and coatings engineered to self-assemble within veins provide scaffolds for vascular tissue growth. This manuscript reviews chitosan hydrogel fabrication methods and their corresponding materials properties, with particular emphasis on drug delivery to vascular tissues. Furthermore, relevant findings from clinical trials are summarized to support the potential of chitosan hydrogels for future clinical use. Challenges of chitosan hydrogels, such as insufficient mechanical strength, high degradation rates, and complex manufacturing, remain as areas for research break-through. Full article

Bone defects from trauma, tumour resection, infection, and degenerative disease remain a major clinical burden, and autografts face limitations of supply and donor-site morbidity. Three-dimensional (3D) printing offers a route to patient-specific, architecturally defined bone scaffolds, while biopolymers from natural sources provide biodegradability, biocompatibility, and extracellular matrix-mimicking cues consistent with sustainable, green biomaterials science. This review synthesises recent progress in 3D printing of biopolymer-based scaffolds for bone tissue engineering. We first examine the principal feedstocks—alginate, gelatin and gelatin methacryloyl, collagen, chitosan, silk fibroin, cellulose, and microbial polyesters—and their preparation, crosslinking chemistry, and printability. We then compare extrusion, light-based, and indirect printing technologies and the process–property relationships governing resolution, mechanical competence, and cell viability. Composite and functionalisation strategies, including biopolymer–bioceramic hybrids and controlled delivery of growth factors and antimicrobial agents, are analysed as routes to osteoinduction, vascularisation, and infection control. Finally, we evaluate translational performance in preclinical models and outline central challenges of vascularisation, mechanical–degradation matching, scalability, and regulatory standardisation. Biopolymer 3D printing is positioned as a ve rsatile, sustainable platform whose clinical maturation depends on integrated material, structural, and biological design. Full article

This study evaluates the intrinsic osteogenic potential of β-tricalcium phosphate (β-TCP)-containing composite scaffolds (PLCL–TCP, PLGA–TCP, and ZnO–TCP) on chorion-derived mesenchymal stem cells (CMSCs) under non-osteogenic in vitro conditions. CMSCs were cultured on the three biomaterials for 35 days without osteogenic supplements to isolate the material-driven cellular response. Cell viability was assessed via MTT assay, while osteogenesis-associated markers (alkaline phosphatase, type I collagen, and osteocalcin) were quantified using ELISA. Scaffold surface morphology and elemental composition were characterized before and after cultivation utilizing SEM and EDX. All investigated scaffolds supported long-term CMSC viability and induced measurable osteogenic responses. PLCL–TCP demonstrated a consistently strong biological response, characterized by sustained metabolic activity, elevated ALP and COL I production, and increased osteocalcin levels at later stages of cultivation. ZnO–TCP also exhibited favorable osteogenesis-associated responses, particularly with respect to late-stage osteocalcin production, while maintaining high structural stability. In conclusion, β-TCP composites can intrinsically modulate CMSC behavior without biochemical supplements. Osteogenic outcomes depend on a complex interplay of surface chemistry, scaffold architecture, and degradation profiles, with PLCL–TCP demonstrating favorable overall performance among the investigated biomaterials. Full article

Polymer coatings are integral to nearly every modern cardiovascular and endovascular device, including drug-eluting stents (DESs) and drug-coated balloons (DCBs), bioabsorbable vascular scaffolds (BVSs), occluders, grafts, and catheter and guidewire hydrophilic surfaces. Persistent complications, including late stent thrombosis, delayed endothelialization, hypersensitivity, and restenosis, show that coatings actively shape biological responses rather than acting as inert drug carriers. Their surface chemistry, drug release kinetics, and degradation behavior are upstream determinants of blood– and tissue–material responses that govern healing and failure. This review frames coating selection as a structure–property–biological response problem. It surveys the major classes of synthetic polymer coatings and the defining surface and bulk properties. This review also examines how composition and architecture control drug release, and traces the interfacial cascade of protein adsorption, coagulation and complement activation, platelet and leukocyte responses, and neutrophil extracellular trap (NET) formation. These mechanisms are linked to contemporary design strategies that improve hemocompatibility, limit thrombosis, promote endothelial recovery, and tune degradation, and to the standardization and translation gaps that remain. The central message is that polymer coatings are not biologically equivalent. Their surface chemistries and degradation profiles determine the thrombo-inflammatory outcomes. Therefore, coating design should be guided by intended biological response, not drug release alone. Full article

Impaired wound healing arises from interacting biological and material challenges, including persistent infection, biofilm formation, oxidative stress, unresolved inflammation, impaired angiogenesis, defective epithelialization, hemorrhage, and insufficient real-time assessment of wound status. Quantum dot (QD) and nanodot nanosystems have emerged as a versatile class of bioactive wound interfaces capable of addressing these barriers through functions that extend beyond passive coverage. This review synthesizes the design rationale, material composition, validation strategies, functional outcomes, mechanistic interpretation, and translational relevance of QD-enabled platforms for precision wound repair. Across the reviewed literature, carbon dots, graphene QDs, black phosphorus QDs, metal and metal oxide QDs, transition-metal nanodots, and hybrid nanocomposites were incorporated into hydrogels, films, sponges, nanofibers, microneedles, scaffolds, membranes, sprays, and injectable matrices. Their major precision-enabling attributes include localized antimicrobial and antibiofilm activity, redox-adaptive behavior, photothermal and photodynamic activation, inflammatory and macrophage modulation, hemostasis, controlled therapeutic delivery, angiogenic and epithelial support, and fluorescence-based monitoring. The strongest conceptual advance is the transition from static wound dressings toward adaptive biointerfaces that can sense, respond to, or compensate for local wound state abnormalities. Nevertheless, the field remains largely preclinical, with important gaps in long-term safety, standardized characterization, clinically predictive models, manufacturing reproducibility, regulatory alignment, and human validation. Future progress will depend on rationally simplified multifunctional platforms, rigorous comparative testing, wound state-specific evaluation frameworks, and translation-oriented safety and usability studies. QD nanosystems therefore represent a promising foundation for precision wound repair, provided that their multifunctionality is matched by equally rigorous evidence of safety, reproducibility, and clinical relevance. Full article

Background: The generation of durable and hemocompatible small-diameter vascular grafts remains a major challenge in current vascular tissue engineering, as clinically available synthetic grafts are lacking hemocompatibility resulting in limited long-term patency. In recent years, fibrin has emerged as a promising scaffold material for various tissue engineering approaches due to its autologous nature, controllable fabrication, and mechanical properties. However, although pivotal for the translation into clinical application, systematic evaluation of hemocompatibility in fibrin-based small-caliber grafts is still missing. Methods: Here, the hemocompatibility of small-diameter fibrin-based grafts with and without heparin coating was compared to the current gold standard for prosthetic small-diameter vessel replacement in the form of heparin-coated ePTFE grafts using the Chandler Loop circulation model with human whole blood. Cell adhesion of thrombocytes, erythrocytes, and leucocytes was compared. Platelet activation, activation of the complement system, and plasmatic coagulation activity were assessed by ELISA analyses for P-Selectin, complement sC5b-9, and thrombin–antithrombin complex, respectively. Scanning electron microscopy (SEM) was performed to evaluate interactions and thrombocyte activation on the luminal graft surfaces. Results: The short-term hemocompatibility of the fibrin-based grafts with respect to the cell-count, activation of the coagulation pathways, and thrombocyte activation was comparable to the heparin-coated synthetic grafts even without heparin coating of the bioartificial grafts. Conclusions: The findings of this early-stage analysis support fibrin as a promising scaffold material for small-diameter vascular tissue engineering. Full article

Musculoskeletal disorders involving bone, cartilage, tendon, and joint tissues represent a leading cause of disability worldwide, and conventional surgical and graft-based interventions are limited by donor site morbidity, incomplete integration, and finite durability. Despite substantial preclinical progress, translation into reliable clinical benefit has remained inconsistent. This narrative review synthesizes recent advances in bioengineered approaches to bone and joint repair, emphasizing how materials design and regenerative strategy selection influence translational feasibility. Advances in scaffold-based systems highlight the role of material composition, architectural organization, and structure–function matching in supporting musculoskeletal regeneration. Regenerative platforms including stem cell therapies, extracellular matrix-derived constructs, and smart materials are evaluated for biological performance, manufacturability, and regulatory feasibility. Early translational and clinical studies demonstrate encouraging outcomes across selected musculoskeletal indications; however, variability in efficacy and adoption highlights persistent barriers to broader implementation. Key challenges include scalable manufacturing, cost and reimbursement uncertainty, and heterogeneity in clinical infrastructure, factors that may also influence access to advanced regenerative therapies. Future innovations should emphasize manufacturability and real-world evidence generation that align with practical clinical pathways. Full article

This study presents a transformative “one-pot” biorefinery approach for the simultaneous production of hyaluronic acid (HA) and polyhydroxybutyrate (PHB) using an engineered, non-pathogenic Halomonas bluephagenesis TD01 chassis. By leveraging the principles of Next-Generation Industrial Biotechnology (NGIB), a one-step fermentation process was developed in nutrient-rich 40-LBG-Y medium, achieving a balanced metabolic flux that yielded 1.99 g/L and high-molecular-weight (HMw) HA (9.6 × 10⁶ Da) as the highest HA-Mw reported by heterogeneous bacteria, alongside intracellular PHB (0.68 to 1.6 g/L). A bioactive HA-PHB nanoparticle scaffold was fabricated, exhibiting a highly porous, interconnected 3D sponge-like architecture with a significant particle size shift from 12 nm to 450 nm, confirming successful polymer complexation. Antimicrobial evaluations revealed that the scaffold exhibited preliminary antimicrobial potential against representative Gram-positive and Gram-negative strains against Staphylococcus aureus, Klebsiella variicola, and Candida albicans. Notably, while Pseudomonas aeruginosa metabolically exploited purified HA, the integrated scaffold reversed this effect, providing preliminary antimicrobial potential by sterically hindering bacterial hyaluronidases. Furthermore, Halomonas-derived HA consistently outperformed Moringa oil and complex emulsions in preliminary tests against a wide range of pathogenic microbes. These results demonstrate that this dual-product platform provides a sustainable, cost-effective source of high-performance functional materials for advanced antimicrobial coatings and clinical wound management. Full article

The extracellular matrix (ECM) provides a dynamic microenvironment that regulates cell proliferation, migration, and tissue remodeling during wound healing. However, replicating the structural and functional complexity and ECM heterogeneity of native skin ECM remains challenging with conventional single-material hydrogels. Recent advances in multimaterial 3D bioprinting have enabled the spatial integration of diverse biomaterials within a single construct. Lignocellulose has attracted increasing attention as a promising biomaterial for recreating key structural features of the native ECM because of its fibrous architecture, mechanical strength, and biocompatibility. This review offers a comprehensive and integrated perspective on the use of lignocellulose-based multimaterial printing to recreate ECM-mimicking architectures, an underexplored area at the intersection of biomaterials and biofabrication. The roles of cellulose, hemicellulose, and lignin in printability, scaffold stability, porosity, bioactivity, and wound-healing performance are discussed. Representative studies have demonstrated that lignocellulose-based multimaterial bioinks provide porous architectures that support cell adhesion, proliferation, and tissue regeneration. These benefits are accompanied by improved mechanical performance, as cellulose nanofibers exhibit elastic moduli exceeding 100 GPa, and lignin-containing hydrogels have achieved compressive moduli of up to 135 kPa. Such mechanical advantages make lignocellulosic materials particularly attractive for fabricating ECM-mimicking scaffolds that require long-term structural integrity. Finally, key design considerations and current limitations associated with lignocellulose-based multimaterial bioprinting are critically discussed. A framework for the rational design of lignocellulose-based multimaterial bioinks is presented, together with future directions toward gradient and adaptive scaffolds, smart wound dressings, and advanced wound-healing applications. Full article

Polyhydroxyalkanoates (PHAs) are bio-based, biodegradable polyesters increasingly explored as sustainable biomaterials for regenerative medicine. This review summarizes recent advances in PHA-based bone substitute materials, highlighting their properties, fabrication methods, and biological performance. PHAs combine biocompatibility, tunable mechanical behavior, and degradation into non-toxic metabolites, while copolymerization and monomer selection modulate the stiffness, crystallinity, and resorption rate. Processing techniques such as solvent casting, electrospinning, and additive manufacturing allow the production of porous architectures that mimic bone extracellular matrix. Electrospinning is particularly suitable for nanoscale fibrous matrices, whereas 3D printing enables patient-specific scaffolds with controlled geometry and interconnected porosity. Scaffold performance can be further improved through the incorporation of osteoconductive fillers, including hydroxyapatite, β-tricalcium phosphate, bioactive glasses, graphene oxide, and carbon nanotubes, as well as through drug-delivery and pro-angiogenic functionalization. In vitro and in vivo studies consistently report favorable cytocompatibility, enhanced osteogenic differentiation, vascularization, and effective repair of bone defects in animal models. However, clinical translation remains limited by production costs, variability in polymer quality, thermal processing constraints, and regulatory challenges. Future progress will rely on more efficient biosynthesis, medical-grade purification, multifunctional scaffold design, and stronger collaboration between academia, industry, and clinicians to unlock the full potential of PHAs in regenerative bone therapies. Full article

Self-powered integrated electrochemical systems require electrode materials that can simultaneously provide energy storage and sensing functions. Boron-doped diamond (BDD) electrodes have good chemical stability and a wide potential window, but their small specific surface area and slow interfacial charge transfer limit their use in such bifunctional applications. In this work, we prepared a three-dimensional porous BDD scaffold on titanium foam by hot-filament chemical vapor deposition, and then grew polypyrrole (PPy) layers on the scaffold by in situ oxidative polymerization. The polymerization time was varied from 8 to 20 h. The BDD/PPy composite obtained after 12 h showed an areal capacitance of 398.6 ± 15.2 mF/cm² at 1 mA/cm², which is about 5.8 times that of the porous BDD alone (67.9 mF/cm²). Its charge transfer resistance (R_ct) was as low as 1.3 ± 0.1 Ω, among the lowest reported for BDD-based electrodes. The porous BDD framework provides ion diffusion pathways, while the PPy layer introduces pseudocapacitance. X-ray photoelectron spectroscopy reveals that the PPy layer contains pyrrolic –NH– groups, which are known to chelate various water pollutants (e.g., heavy metal ions and organic molecules). Based on these surface properties and the low R_ct, we suggest that this composite may have theoretical potential for preconcentrating and detecting multiple pollutants. This work demonstrates a way to improve the capacitance of BDD-based electrodes and may serve as a starting point for future exploration in integrated energy-sensing devices after experimental validation. Full article

Direct utilization of biomass-derived silica in neutral surfactant-templated mesoporous synthesis remains underexplored with respect to mesostructure control and functional integration. High-purity silica extracted from acid-treated rice husk ash (~98.4 wt% SiO₂) was employed as the sole precursor in a fluoride-assisted sol–gel route to synthesize MSU-X frameworks without chemical modification. Systematic parametric variation—pH, Si/surfactant ratio, hydrothermal temperature, and aging duration—establishes quantitative structure–processing correlations. Under optimized conditions (pH 2, Si/Tergitol = 8, 60 °C, 96 h), the resulting material exhibits a wormhole-like mesoarchitecture with a BET surface area of 816 m² g⁻¹, mean pore diameter of ~3.6 nm, and three-dimensionally interconnected channels, confirmed by SAXS, TEM, and N₂ sorption. EDXRF analysis confirms effective impurity removal and high silica incorporation efficiency (~95–96%); thermal stability persists to 700 °C, with incipient crystallization near 800 °C. As a functional demonstration, MSU-X served as an anti-agglomeration scaffold for ZIF-8 crystallization during DDT adsorption. Despite attenuated kinetics relative to pristine ZIF-8—where severe agglomeration occludes active imidazole nodes—the Z8/MSU-X composite achieved near-quantitative DDT removal (74.10 mg g⁻¹). This performance stems from the mesoporous matrix driving size-confined, highly dispersed ZIF-8 growth, thereby maximizing active-site exposure. Operating within a reagent-limited regime rather than a capacity-saturated boundary, this efficient depletion confirms that the scaffold successfully suppresses site loss. Ultimately, these findings validate biogenic silica as a directly integrable precursor for tailored mesostructure assembly, positioning agricultural waste as a high-performance feedstock for hierarchical adsorption architectures. Full article

Tissue engineering and regenerative medicine (TERM) rely on advanced biomaterials and scaffolds that require strict sterilization without sacrificing their structural and functional properties. Conventional sterilization methods, including steam, ethylene oxide, and gamma irradiation, often compromise scaffold integrity, alter surface chemistry and/or leave toxic residues. Ozone (O₃) has emerged as a promising alternative sterilant because of its strong oxidizing potential, broad-spectrum antimicrobial activity, and residue-free decomposition. Importantly, ozone sterilization can preserve—and in some cases enhance—scaffold bioactivity by maintaining cytocompatibility and favorable surface chemistries that support cell adhesion and differentiation. This review critically evaluates the role of ozone sterilization in the context of TERM applications, focusing on its physicochemical properties, disinfection kinetics, material compatibility and regulatory perspectives. Evidence from studies on polymethyl methacrylate (PMMA) scaffolds, bone implants, and hydrogel-based systems suggests that, under optimized conditions, ozone can achieve high sterilization efficacy without significant degradation of mechanical or chemical properties. However, challenges related to process validation, health and safety considerations, and scalability remain. The review highlights opportunities for integrating ozone into automated biomanufacturing workflows and identifies key research gaps to support the broader adoption of ozone sterilization in TERM applications. Full article