Search Results (2,076)

Background/Objectives: The main objective of optimizing the composition of dental implants is to improve tissue compatibility for enhanced biological/biochemical performance. In this context, research on the development of new titanium alloys in dental implantology considers the careful selection of alloying elements, both in terms of biocompatibility (their lack of toxicity) and their potential to improve the metallurgical processing capacity (thermal and/or thermomechanical), which through controlled microstructural changes lead to the optimal combination of properties for functionality and durability of the implant. The purpose of the research is to study the influence of alloying elements on the phase composition and physical–mechanical properties of experimental titanium alloys. Methods: Four alloys with original chemical compositions were developed, coded in the experiments as follows: Ti1, Ti2, Ti3, Ti4. The characterization of the alloys was carried out by detailed analysis of the chemical composition, phase structure and by testing the physico-mechanical properties (HV hardness, tensile strength, yield strength, elongation, modulus of elasticity), by standardized modern methods. Characterization methods, such as optical microscopy, SEM, EDS and XRD were performed, followed by tensile tests based on ASTM EB/EBM-22 and EN ISO 6892-1-2009 standards. Results: The research results provide information regarding the relationship between the composition and the physico-mechanical properties (Rm, Rp, HV, A, G, E) of the experimental alloys (Ti1–Ti4). Depending on the value level of the properties, these have been highlighted: compositions in which the alloy can be indicated for conditions of intense stress (Ti3), compositions that describe highly ductile alloys, easy to process and adapt to clinical requirements (Ti4), but also alloys compositions characterized by a balanced combination of strength, plasticity/ductility (Ti1, Ti2). Conclusions: Research for the development of new titanium alloys through the optimization of chemical composition has taken into account the requirements regarding the biological/biomechanical compatibility of biomaterials. Analyzed in comparison with Cp-Ti grade 4 and Ti6A4V, the experimental alloys (Ti1–Ti4) can be characterized as follows: The mechanical strength properties (Rm and Rp) are higher than those of pure commercial titanium (Cp-Ti grade 4) for all compositions Ti1–Ti4, but slightly lower than those of alloy Ti6Al4V. The plasticity–ductility properties have values comparable to those of Cp-Ti grade 4 (Ti4 and Ti2 compositions) and Ti6Al4V (Ti1 composition), with one exception, the Ti3 alloy. All four experimental alloys have a lower modulus of elasticity than Cp-Ti grade 4 (102–104 GPa) and Ti6Al4V (113 GPa), commonly used in dental implants. An in-depth analysis, which will also consider information on corrosion behavior and cellular testing, may support the selection of some of the four experimental alloys studied. The research aims to continue the progress to a higher level of testing, through the realization of dental implants (e.g., fatigue, wear, osteointegration capacity, etc.). Full article

Optimizing nanofiber morphology is essential for promoting osteoblast elongation and supporting bone regeneration. This study aimed to develop a machine-learning framework capable of predicting optimal scaffold architectures directly from scanning electron microscopy (SEM) images and chemical composition. A four-module pipeline was implemented, combining tile-based SEM preprocessing, Cellpose-based cell morphology extraction with edge correction, ensemble machine-learning models, and an end-to-end convolutional neural network (CNN). Cellular quality was quantified using an elongation-weighted metric to emphasize morphological maturity over cell number. The analysis revealed consistent structure–function relationships across samples, with Sample_5 achieving the highest quality score at the 72 h time point. Ensemble models reached an R² of 0.400, while the end-to-end CNN achieved an R² of 0.750, indicating that raw SEM texture provides additional predictive information beyond handcrafted features. Feature-importance analysis identified nonlinear MgO effects and synergistic interactions between MgO and gold nanoparticles as key determinants of cell morphology. These findings demonstrate that the integrated workflow can reliably identify morphology–chemistry combinations favorable for osteoblast performance and provide a foundation for data-driven scaffold optimization. The approach supports rational design of nanofibrous biomaterials and may facilitate future development of intelligent scaffolds for bone regeneration applications. Full article

Rosin, a renewable natural resin derived from pine trees, is a promising biomass material for sustainable product development, though its distinct intrinsic odor limits broader use. This study implemented a comprehensive analytical strategy to mitigate the odor by incorporating essential oils (EOs)—eucalyptus (EUC) and peppermint (MINT)—and to conduct a multi-analytical characterization of the modified rosin jewelry. By integrating complementary analytical techniques, including LC-Q/TOF-MS for non-volatile components and GC-Q/TOF-MS for volatile organic compounds (VOCs), we achieved a systematic chemical profiling of the materials. The core composition of rosin, dominated by abietic acid (>48%), remained stable across all samples. The incorporation of EOs significantly altered the VOC profiles: The total VOC signal (summed peak area) in MINT-modified rosin was 2.57-fold that of the EUC-modified sample, with monoterpenoids comprising 87.62% of its VOC signature. Eucalyptol and limonene were tentatively identified as the major components in the EUC sample, whereas menthone, menthol, and limonene predominated in the MINT sample. Multivariate statistical analysis highlighted that variations in specific VOCs—particularly menthone, menthol, eucalyptol, and allo-ocimene—were closely associated with differences in the scent profiles of each modification. This work illustrates how a multi-technique analytical strategy can both guide and assess the functional modification of sustainable biomass materials. The findings offer a practical approach to improving rosin’s functional properties while providing a methodological framework for the integrated characterization of complex biomaterials, supporting the development of eco-friendly products aligned with green chemistry and sustainable design principles. Full article

Click chemistry is highly valued in the design of polymeric biomaterials due to its ability to generate complex structures and localized surface modifications. However, prominent mechanisms in click chemistry, such as copper-catalyzed azide-alkyne cycloaddition (CuAAC), are inefficient for the synthesis and/or modification of biomaterials because they present significant limitations for in vivo applications. The presence of residual copper in the material is toxic and requires extensive purification, increasing production costs and hindering scalability and availability for in vivo applications. To overcome these limitations and ensure the safety and biocompatibility of materials, biorthogonal reactions such as strain-promoted azide-alkyne cycloaddition (SPAAC) have been developed. Thiol-ene/thiol-yne and Diels–Alder mechanisms are also relevant for the formation of robust polymer networks with specific characteristics and attractive advantages for generating biocompatible materials. These reactions not only improve cell integration and reduce fibrosis in in vivo applications but also enable the creation of functional structures for tissue regeneration. This review provides a comprehensive analysis of advances in the synthesis of biomaterials for tissue regeneration using hydrogels designed via click chemistry, as well as the various mechanisms and structural considerations. Full article

Kidney organoids, as three-dimensional microstructures derived from human pluripotent stem cells or adult stem cells, precisely simulate the cellular heterogeneity, spatial conformation, and some physiological functions of human kidney units in vitro. Kidney organoids are three-dimensional microstructures derived from human pluripotent stem cells (hPSCs). They precisely simulate the cellular heterogeneity, spatial conformation, and key physiological functions of human kidney units in vitro. This technology, by replicating the interaction network between the glomerulus and renal tubules, provides an unprecedented window for observing the dynamic development and pathological processes of human kidneys. This technology replicates the interaction network between the glomerulus and renal tubules. It thereby provides an unprecedented window into human kidney development and disease. Based on the strong similarity between organoids and native organs, as well as the human genetic information they carry, both iPSC-derived and patient-specific organoids have demonstrated significant value in kidney disease modeling, drug toxicity testing, and the development of regenerative treatment strategies. This review systematically elucidates the key advancements in the field of kidney organoids, including optimized strategies for stem cell-directed differentiation, innovations in culture systems driven by biomaterials engineering, technological breakthroughs in disease model construction, and applications of organoids in drug screening platforms and regenerative medicine. Additionally, it analyzes translational challenges such as the lack of vascularization, insufficient functional maturity, and obstacles in standardized production. These insights will deepen the understanding of kidney pathological mechanisms and propel organoid technology towards substantial clinical therapeutic applications. This review summarizes how convergent technologies in stem cell biology and bioengineering aim to bridge this functional gap. We examine the use of advanced organoids in disease modeling and drug discovery. We also highlight their current limitations. Our focus is on the core translational bottlenecks: vascularization, long-term maturation, and scalable production. Overcoming these hurdles is essential to transform kidney organoids from a research tool into a platform for precision medicine and regenerative therapy. Full article

Fiber-forming polymers are increasingly used to control blood coagulation, either by accelerating the onset of hemostasis or by limiting thrombogenic events in contact with blood. Despite rapid progress in materials engineering, a unified view linking the molecular mechanisms of the coagulation cascade with specific design strategies of procoagulant and anticoagulant polymeric fibers is still missing. In this review, we summarize current knowledge on how natural and synthetic polymers interact with plasma proteins, platelets, and coagulation factors, emphasizing the role of fiber morphology, surface chemistry, charge distribution, and functionalization. Particular attention was paid to systems based on natural polysaccharides (e.g., chitosan, alginate, and cellulose derivatives), as well as synthetic polymers (e.g., PLA, PCL, polyurethanes, and zwitterionic materials). Two possible courses of action were described: their bioactivity may activate the contact pathway and/or support platelet adhesion or their ability to minimize protein adsorption and inhibit thrombin generation. We discuss how metal–polymer coordination, surface immobilization of heparin or nitric oxide donors, and nanoscale texturing modulate coagulation kinetics in opposite directions. Finally, we highlight emerging fiber-based strategies for achieving either rapid hemostasis or long-term hemocompatibility and propose design principles enabling precise tuning of coagulation responses for wound dressings, vascular grafts, and blood-contacting devices. This general compendium of knowledge on blood–material interactions provides a foundation for further design of biomaterials based on fiber-forming polymers and the development of manufacturing processes. Full article

Synthesized by expressing natural collagen sequences in specific hosts, recombinant collagen exhibits multiple advantages, encompassing a higher content of bioactive domains, enhanced antioxidant activity, the absence of viral pathogens, favorable hydrophilicity, reproducible production, and low immunogenicity. Consequently, it has found extensive use in applications ranging from biomaterials and pharmaceuticals to skincare. This review systematically explores various expression systems for recombinant collagen, including those utilizing Escherichia coli, Pichia pastoris, plants, insect baculovirus, and mammalian cells. It provides a detailed comparison of their differences and commonalities in terms of production efficiency, post-translational modification capability, and cost-effectiveness. Key separation and purification techniques for recombinant collage-notably precipitation, affinity chromatography, ion-exchange chromatography, and gel filtration chromatography are further introduced, with an in-depth analysis of the applicable scenarios and purification outcomes for each method. Finally, the review comprehensively summarizes the characterization methods for both the physicochemical properties and biological functions of recombinant collagen. For physicochemical properties, techniques covered include scanning electron microscopy, micro-differential thermal analysis, circular dichroism spectroscopy, SDS-PAGE, mass spectrometry, and Fourier-transform infrared spectroscopy. For biological functions, the focus is on its roles and the corresponding assessment methods in processes such as cell proliferation, migration, adhesion, and wound healing. Building upon this comprehensive overview, current challenges facing recombinant collagen are identified, and future directions are proposed, emphasizing the need to reduce R&D costs, refine testing methods for cosmetic products, and improve safety evaluation protocols to advance the field. Full article

Cryopreservation is a critical strategy for the long-term conservation of plant germplasm, particularly for clonally propagated crops, endangered species, and plants producing recalcitrant seeds. Hydrogel-based encapsulation systems can improve survival during ultra-low-temperature storage by providing mechanical protection, moderating dehydration, and regulating cryoprotectant uptake. Although calcium–alginate beads remain the traditional matrix for encapsulation–dehydration and encapsulation–vitrification, recent advances in biomaterials science have enabled the development of composite polysaccharide blends, protein-based matrices, synthetic polymer networks, macroporous cryogels, and functionalized hybrid hydrogels incorporating surfactants, antioxidants, or nanomaterials. These engineered systems provide improved control over water state, pore architecture, diffusion kinetics, and thermal behavior, thereby reducing cryoinjury and enhancing post-thaw recovery across diverse plant explants. This review synthesizes current knowledge on hydrogel platforms used in plant cryopreservation, with emphasis on how physicochemical properties influence dehydration dynamics, cryoprotectant transport, vitrification stability, and rewarming responses. Performance across major explant types is assessed, key limitations in existing materials and protocols are identified, and design principles for next-generation hydrogel systems are outlined. Future progress will depend on material standardization, integration with automated cryopreservation workflows, and the development of responsive hydrogel matrices capable of mitigating cryogenic stresses. Full article

Additive manufacturing offers rapid and customizable production, yet conventional plastic-based methods remain energy-intensive and environmentally harmful, often resulting in higher impacts per part than traditional manufacturing. The goal of this study was to evaluate whether upcycled biomaterials, specifically oyster shells, pistachio shells, and clay, could be used as lower-impact alternatives to PLA in 3D printing. The scope included detailed measurement of print parameters for each material and a full life cycle assessment (LCA) of the printed elements, covering printer manufacturing, raw material extraction, transport, operation, and end of life. The results show that ambient-temperature extrusion of these upcycled biomaterials can reduce energy consumption by up to 89% and overall environmental impact by up to 94% (as measured by ReCiPe Endpoint H points) compared to PLA printing. These reductions were observed for the Netherlands and EU contexts, where electricity mixes are relatively clean and recycling rates are high; even greater improvements were observed for the US. Although the printed biomaterial objects exhibit lower mechanical strength, limited waterproofness, and reduced print resolution, they are already suitable for low-load applications such as prototypes and architectural models. Overall, the findings demonstrate that upcycled biomaterial extrusion has strong sustainability potential, outperforming both conventional plastics and bioplastics such as PLA in terms of material impacts and energy use. Continued development of material formulations as well as pre- and post-processing techniques could further expand functionality and support the broader adoption of low-impact 3D printing across a wide range of applications. Full article

The accelerating global demand for sustainable energy, driven by population growth, industrialization, and environmental concerns, has intensified the search for renewable alternatives to fossil fuels. Biofuels, including bioethanol, biodiesel, biogas, and biohydrogen, offer a viable and practical pathway to reducing net carbon dioxide (CO₂) emissions. Yet, their large-scale production remains constrained by biomass recalcitrance, high pretreatment costs, and the enzyme-intensive nature of conversion processes. Recent advances in enzyme immobilization using magnetic nanoparticles (MNPs), covalent organic frameworks, metal–organic frameworks, and biochar have significantly improved enzyme stability, recyclability, and catalytic efficiency. Complementary strategies such as cross-linked enzyme aggregates, carrier-free immobilization, and site-specific attachment further reduce enzyme leaching and operational costs, particularly in lipase-mediated biodiesel synthesis. In addition to biocatalysis, nanozymes—nanomaterials exhibiting enzyme-like activity—are emerging as robust co-catalysts for biomass degradation and upgrading, although challenges in selectivity and environmental safety persist. Green synthesis approaches employing plant extracts, microbes, and agro-industrial wastes are increasingly adopted to produce eco-friendly nanomaterials and bio-derived supports aligned with circular economy principles. These functionalized materials have demonstrated promising performance in esterification, transesterification, and catalytic routes for biohydrogen generation. Technoeconomic and lifecycle assessments emphasize the need to balance catalyst complexity with environmental and economic sustainability. Multifunctional catalysts, process intensification strategies, and engineered thermostable enzymes are improving productivity. Looking forward, pilot-scale validation of green-synthesized nano- and biomaterials, coupled with appropriate regulatory frameworks, will be critical for real-world deployment. Full article

Vascularised composite allotransplantation (VCA) has an evolving role in the reconstruction of complex functional and aesthetic deficits non-amenable to autologous or implant-based reconstructive modalities. International applications of VCA span upper extremity, face, abdominal wall, uterus, and penile transplantation, with more than 300 procedures performed worldwide. Among these, abdominal wall transplantation has uniquely contributed to the development of the sentinel skin flap (SSF) concept, in which solid organ transplant patients undergo simultaneous transplantation of a solid organ and a donor-derived vascularised skin flap, with the skin component of the SSF being trialled internationally as a means of monitoring for rejection within the solid organ allograft. Despite growing clinical success, VCA continues to face substantial barriers to wider adoption. Acute rejection remains highly prevalent, affecting up to 89% of recipients, with significant morbidity linked to intensive systemic immunosuppression. Challenges are further amplified by the unique immunological heterogeneity of composite grafts, ethical concerns surrounding identity-linked tissues, and the lack of standardised outcomes reporting across VCA subtypes. Advances in machine perfusion technologies and emerging cellular and biomaterial-based immunomodulation strategies show promise in reducing immunosuppression burden and improving graft longevity. This review outlines the current state of VCA, including clinical applications, outcomes, and mechanistic insights from pre-clinical studies, while highlighting key ethical considerations and evolving regulatory frameworks. Future progress will depend on standardised reporting systems, improved donor–recipient matching, better understanding of ischemia–reperfusion injury, and the development of next-generation immunosuppressive/immuno-modulatory therapies. Collectively, these innovations position VCA as a rapidly advancing field with significant potential to redefine reconstructive and transplant surgery. Full article

Advances in kidney organoid technologies have expanded opportunities to model human renal development, disease, and therapeutic response. Yet pluripotent stem cell-derived organoids remain limited by cellular heterogeneity, incomplete tubular maturation and low scalability, restricting their translational relevance. Tubular-specific organoids, derived from adult kidney epithelium, address many of these constraints by providing stable, reproducible cultures enriched for functional proximal and distal tubular cells. Their polarized transport, metabolic activity and patient-specific phenotypes enable high-fidelity modeling of acute and chronic tubular disorders, nephrotoxicity, and inherited tubulopathies—areas where conventional animal and cell-line models often fall short. In this Perspective, we outline recent advances that position tubuloids as a versatile platform for drug screening, toxicity testing and personalized disease modeling. We highlight emerging integration with microfluidics, biomaterials, and gene-editing strategies that promise greater physiological realism and precision therapeutics. We also discuss persistent barriers that impede broader adoption and clinical translation. We propose a roadmap for advancing tubuloid technologies toward precision nephrology and their future incorporation into diagnostic, pharmacological and regenerative pipelines. Full article

This study reports the synthesis and detailed characterization of pullulan-isononanoate (Pull-Iso), as well as the preparation and characterization of Pull-Iso films incorporating liposomes loaded with silibinin (SB) and smoke tree (Cotinus coggygria) extract (STExt), to explore the physicochemical and functional properties of pullulan-based biomaterials for potential biomedical applications. Pullulan was successfully esterified with isononanoic acid chloride, as confirmed by ¹H and ¹³C NMR (Nuclear Magnetic Resonance) and Fourier Transform Infrared (FTIR) spectroscopy. Modification significantly reduced the glass transition temperature (Tg), indicating enhanced chain mobility due to the introduction of bulky side chains. Prepared liposomes, embedding SB and extracted smoke tree compounds, exhibited particle sizes ~2000 nm with moderate polydispersity (~0.340) and zeta potential values around –20 mV, demonstrating lower colloidal stability over 60 days, thereby justifying their encapsulation within films. Optical microscopy revealed uniform liposome dispersion in Pull-Iso film with 0.5 g of liposomes, while higher liposome loading (0.75 g of liposomes) induced aggregation and microstructural irregularities. Mechanical analysis showed a reduction in tensile strength and strain at higher liposome content. The incorporation of liposomes encapsulating STExt and SB significantly enhanced the antioxidant activity of Pull-Iso-based films in a concentration-dependent manner, as demonstrated by DPPH and ABTS radical scavenging assays. These preliminary findings suggest that pullulan esterification and controlled liposome incorporation may enable the development of flexible, bioactive-loaded films, which could represent a promising platform for advanced wound dressing applications, warranting further investigation. Full article

Regenerative medicine is increasingly leveraging the synergies between bioinspired conductive biomaterials and 3D/4D bioprinting to replicate the native electroactive and hierarchical microenvironments essential for functional tissue restoration. However, a critical gap remains in the intelligent integration of these technologies to achieve dynamic, responsive tissue regeneration. This review introduces a “bioinspired material–printing–function” triad framework to systematically synthesize recent advances in: (1) tunable conductive materials (polymers, carbon-based systems, metals, MXenes) designed to mimic the electrophysiological properties of native tissues; (2) advanced 3D/4D printing technologies (vat photopolymerization, extrusion, inkjet, and emerging modalities) enabling the fabrication of biomimetic architectures; and (3) functional applications in neural, cardiac, and musculoskeletal tissue engineering. We highlight how bioinspired conductive scaffolds enhance electrophysiological behaviors—emulating natural processes such as promoting axon regeneration cardiomyocyte synchronization, and osteogenic mineralization. Crucially, we identify multi-material 4D bioprinting as a transformative bioinspired approach to overcome conductivity–degradation trade-offs and enable shape-adaptive, smart scaffolds that dynamically respond to physiological cues, mirroring the adaptive nature of living tissues. This work provides the first roadmap toward intelligent electroactive regeneration, shifting the paradigm from static implants to dynamic, biomimetic bioelectronic microenvironments. Future translation will require leveraging AI-driven bioinspired design and organ-on-a-chip validation to address challenges in vascularization, biosafety, and clinical scalability. Full article

Tympanic membrane (TM) perforations, arising from infections, injuries, or chronic otitis media, remain a frequent clinical finding and can lead to hearing problems when the tissue does not regenerate adequately. Although autologous grafts are still the standard option for repairing persistent defects, they come with well-known limitations. Beyond the need for additional harvesting procedures, these grafts rarely reproduce the intricate, fibrous layering of the native TM, which can compromise sound transmission after healing. In search of alternatives, fibre-based scaffolds have attracted considerable interest. The primary advantage of this material is the level of structural control it affords. The fibre orientation, porosity, and overall microarchitecture can be adjusted to replicate the organisation and mechanical behaviour of the natural membrane. A range of biocompatible polymers—among them silk fibroin, poly(ε-caprolactone), poly(lactic acid), and poly(vinyl alcohol) and their composites—provide options for tuning stiffness, degradation rates, and interactions with cells, making them suitable building blocks for TM repair constructs. This review provides a comprehensive overview of contemporary fabrication methodologies, namely electrospinning, additive manufacturing, melt electrowriting, and hybrid strategies. In addition, it offers a detailed discussion of the evaluation procedures employed for these scaffolds and discusses how scaffold structure affects later performance. Mechanical testing, microstructural imaging, and in vitro biocompatibility assays help to determine how closely a construct can approach the performance of the native tissue. Bringing these elements together may support the gradual translation of fibre-based TM scaffolds into clinical practice. Full article