Search Results (1,587)

Electroactive biomaterials are a key emerging technology for the treatment of neural damage. Conducting polymer-coated carbon microfibers are particularly useful for this application because they provide directional support for cell growth and tissue repair and simultaneously allow for ultrasensitive recording and stimulation of neural activity. Here, we report in vitro experiments investigating the biology of Schwann cells (SCs), a major player in peripheral nerve regeneration, on electroconducting microfibers. The optimal molecular composition of the cell substrate and cell culture medium was studied for SCs dissociated from rat and pig peripheral nerves. The substrate molecules were then attached to carbon microfibers coated with poly (3,4-ethylenedioxythiophene) doped with poly [(4-styrenesulfonic acid)-co-(maleic acid)] (PCMFs), which served as an electroactive scaffold for culturing nerve explants. Biphasic electrical stimulation (ES) was applied through the microfibers, and its effects on cell proliferation and migration were assessed in different cell culture media. Rodent and porcine SCs avidly migrated on PCMFs functionalized with a complex of poly-L-lysine, heparin, basic fibroblast growth factor, and fibronectin. Serum and forskolin/heregulin increased, by two-fold and four-fold, the number of SCs on PCMFs, respectively, and ES further doubled cell numbers without favoring fibroblast proliferation. ES additionally increased SC migration. These results provide a baseline for using biofunctionalized PCMFs in peripheral nerve repair. Full article

Bone defects remain a significant clinical challenge, creating a severe need for advanced biomaterials for tissue regeneration. This study addresses this issue by developing 3D-printed composite hydrogels containing alginate, gelatine, and resorbable calcium phosphates (monetite and brushite) for bone tissue engineering. The scaffolds were fabricated using extrusion-based 3D printing and evaluated for their morphology, porosity, mechanical strength, swelling, degradation, and in vitro mineralization, while their cytocompatibility was assessed using LIVE/DEAD cell viability assays. The key findings demonstrate that calcium phosphate incorporation enhanced the mechanical stability by 15–25% compared to the controls, and mineral deposition increased significantly in the composite scaffolds. The developed hydrogels are bioactive and represent promising, customizable scaffolds for bone regeneration. These results support their further investigation as viable alternatives to traditional bone grafts for clinical bone tissue engineering applications. Full article

The CaO-SiO₂-P₂O₅ system is one of the main systems studied aiming for the synthesis of new bioactive materials for bone regeneration. The interest in materials containing calcium-phosphate-silicate phases is determined by their biocompatibility, biodegradability, bioactivity, and osseointegration. The object of the present study is the synthesis by the sol-gel method of biocompatible glass-ceramics in the Ca₂SiO₄-Ca₃(PO₄)₂ subsystem with the composition 6Ca₂SiO₄·Ca₃(PO₄)₂ = Ca₁₅(PO₄)₂(SiO₄)₆. The phase-structural evolution of the samples was monitored using X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and surface area analysis. A powder (20–30 µm) glass-ceramic material containing fine crystalline aggregates of dicalcium silicate and plates of silicon-substituted hydroxyapatite was obtained after heat treatment at 700 °C. After heat treatment at 1200 °C, Ca₁₅(PO₄)₂(SiO₄)₆, silicocarnotite Ca₅(PO₄)₂(SiO₄), and pseudowollastonite CaSiO₃ were identified by XRD, and the particle size varied between 20 and 70 µm. The compact glass-ceramic obtained at 1400 °C contained Ca₂SiO₄-Ca₃(PO₄)₂ solid solutions with an α-Ca₂SiO₄ structure as a main crystalline phase. SEM showed the specific morphology of the crystalline phases and illustrated the trend of increasing particle size depending on the synthesis temperature. Effects of the glass-ceramic materials on cell viability of HL-60-derived osteoclast-like cells and on the expression of apoptotic and osteoclast-driven marker suggested that all materials at low concentrations, above 1 µg mL⁻¹, are biocompatible, and S-1400 might have a potential application as a scaffold material for bone regeneration. Full article

Biocompatible polymers have emerged as essential materials in medical 3D printing, enabling the fabrication of scaffolds, tissue constructs, drug delivery systems, and biosensors for applications in and on the human body. This review aims to provide a comprehensive overview of the current state of 3D-printable biocompatible polymers and their composites, with an emphasis on their processing methods, properties, and biomedical uses. The scope of this work includes both natural and synthetic biocompatible polymers, polymer–nanocomposite systems, and bioinks that do not require photo initiators. The relevant literature was critically examined to classify materials by type, evaluate their compatibility with major 3D printing techniques such as stereolithography, selective laser sintering, and fused deposition modeling, and assess their performance in various medical applications. Key findings highlight that reinforced polymer composites, tailored surface chemistries, and hybrid printing strategies significantly expand the range of functional, customizable, and affordable biomedical devices. This review concludes by discussing present-day applications and emerging trends, underscoring that 3D-printable biocompatible polymers are rapidly transitioning from research to clinical practice, offering transformative potential for patient-specific healthcare solutions. Full article

The progress in biopolymers and their composites as advanced materials for wound healing has revolutionized therapeutic approaches for skin regeneration. These materials can effectively integrate their inherent biocompatibility and biodegradability with the enhanced mechanical strength and customizable properties of polymers and functional additives. This review presents a detailed investigation of the design principles, classifications, and biomedical applications of biopolymeric composites, focusing on their capabilities to promote angiogenesis, exhibit antimicrobial activities, and facilitate controlled drug delivery. By overcoming the challenges of conventional wound dressings, such as inadequate exudate management, mechanical fragility, and cytotoxicity, these composites provide dynamic, stimuli-responsive platforms that can adapt to the wound microenvironment. This study further highlights innovative advances in nanoparticle-assisted reinforcement, fiber-based scaffolds, and multi-stimuli responsive smart delivery systems. Finally, the future perspective illustrates how the challenges related to long-term physiological stability, scalable manufacturing, and clinical implementation can be addressed. Overall, this article delivers a comprehensive framework for understanding the transformative impact of biopolymeric composites in next-generation wound care. Full article

Composite scaffolds based on a hydrogel matrix modified with hydroxyapatite, magnesium, or zinc compounds are promising for filling and regenerating osteochondral defects due to the specific biological properties of these modifiers. The aim of this work was to evaluate the influence of hydroxyapatite, nano-hydroxyapatite, magnesium chloride, and zinc oxide on mechanical properties, swelling ability, behavior in a simulated biological environment (ion release, stability, bioactivity), and antibacterial effects. Furthermore, the influence of the hydrogel matrix (alginate, gelatin, alginate/gelatin) on the selected properties was also assessed. The results showed that the addition of ZnO improved the mechanical properties of all types of matrices most effectively. Additionally, zinc ions were gradually released into the environment and partially incorporated into the formed apatite. The released zinc ions increased the inhibition zones of Staphylococcus aureus growth; however, this effect was observed only in scaffolds with an alginate matrix. This indicates that hydrogel plays a key role in antibacterial effects, beyond the contribution of antibacterial additives. No effect of magnesium on bacterial growth inhibition was observed despite its rapid release. Magnesium ions promoted efficient secretion of apatite during incubation, although it was not stable. The addition of nano-HAP significantly increased the stability of the apatite precipitates. Full article

Poly(L-lactic acid) (PLLA) and iron (Fe) are popular bioresorbable material candidates for biomedical implants. However, PLLA coronary stents are relatively too thick compared to metallic stents when providing the same mechanical strength, while iron degrades too slowly. Recent studies show that PLLA coatings can enhance iron’s corrosion rate, and iron has strong mechanical strength, making PLLA–Fe composites ideal for bioresorbable implants. Although PLLA coatings on iron samples have been studied, research on embedding iron wires in relatively thick PLLA matrices is limited. Moreover, no studies have yet explored 3D-printed metal wire-reinforced PLLA monofilaments for biomedical applications. To address these research gaps and investigate the in vitro degradation profile of PLLA/Fe wire monofilaments for bioresorbable stents, this study first developed a novel polymer filament–metal wire coextrusion 3D printer for printing PLLA/Fe wire monofilaments. In vitro degradation tests were then conducted on both PLLA/Fe and neat PLLA monofilaments at 50 °C. Thereafter, characterizations, including mass loss, pH, surface appearance and morphology, tensile tests, gel permeation chromatography (GPC), and differential scanning calorimetry (DSC), were performed. Results indicated that the overall degradation rate of PLLA/Fe monofilaments was higher than that of PLLA counterparts, while the degradation rate of PLLA matrix was not affected by the embedded iron wire according to molecular weight analysis. Notably, the Young’s modulus and stiffness of PLLA monofilaments were significantly improved by the iron wires during the early stages of degradation, but the reinforcement in tensile strength was negative after immersion due to the poor embedding quality of the iron wires in the PLLA monofilaments. With future improvement of the embedding quality of iron wire, the 3D-printed PLLA/Fe wire composites can have great potential in the development of biomedical devices using the novel 3D printing method, including most types of stents and bone scaffolds. Full article

The global burden of cancer continues to grow, with bone cancer—though rare—posing serious challenges in terms of treatment and post-surgical reconstruction. Autologous bone grafting remains the gold standard, yet limitations such as donor site morbidity drive the search for alternative solutions. Tissue engineering, combining biomaterials and therapeutic agents, offers promising avenues. This study focuses on the development of multifunctional scaffolds based on collagen and hydroxyapatite obtained by the freeze-drying technique and incorporating both synthetic (doxorubicin) and natural (caffeic acid) compounds for osteosarcoma treatment. These scaffolds aim to combine tumor inhibition with bone regeneration, addressing the dual need for local drug delivery and structural repair in bone cancer therapy. The characterization of these composite materials revealed that a spongious structure with interconnected pores and a homogeneous pore distribution, with pore sizes between 20 and 250 μm suitable for osteoblasts infiltration. The Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis-differential scanning calorimetry (TG-DSC) and X-ray diffraction (XRD) analyses confirmed the formation of hydroxyapatite inside the collagen matrix. LDH and XTT assays confirmed that the antitumoral scaffolds possess great potential for osteosarcoma treatment, showing that after 3 days of culturing, the extracts containing doxorubicin-7A, both alone and in combination with caffeic acid-9A, significantly reduced the viability of cell lines to below 7% and 20%, respectively. Full article

Biomaterials modified by antibacterial substances, including nanoparticles, open new opportunities for the effective treatment of infected wounds. Unfortunately, most publications focused only on experiments in vitro, with limited understanding of their potential for the clinic. This study evaluates the effectiveness in vivo of electrospun chitosan/polylactic acid (Ch/PLA) membranes enriched with silver nanoparticles (AgNPs) for purulent wound treatment. The composite biomaterial integrates chitosan’s biocompatibility and antimicrobial activity with PLA’s structural integrity, while AgNPs enhance antibacterial efficacy against major wound pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia aureus. A full-thickness purulent wound model was established in a rat model, and the animals were divided into three treatment groups: (i) Ch/PLA, (ii) Ch/PLA-AgNPs, and (iii) PLA-chlorhexidine (control). Wound healing was monitored over 21 days through macroscopic evaluation, histology, immunohistochemistry, and microbiological analysis. The Ch/PLA-AgNPs membranes significantly reduced bacterial colonization within 4–6 days, promoted granulation tissue formation, and accelerated epithelialization compared to the non-modified Ch/PLA scaffold. By day 15, complete wound closure was observed in the Ch/PLA-AgNPs group, comparable to PLA-chlorhexidine-treated wounds. Immunohistochemical analysis revealed a controlled inflammatory response with a balanced macrophage M1/M2 transition, supporting efficient tissue regeneration. Furthermore, systemic toxicity assessments indicated no significant adverse effects on internal organs. These findings demonstrate that electrospun Ch/PLA-AgNPs membranes effectively accelerate purulent wound healing by combining antimicrobial protection with biocompatible tissue support. This innovative approach presents a promising alternative to conventional wound dressings and paves the way for clinical applications in managing infected wounds. Full article

In this study, a shape-changeable 3D scaffold with photothermal effects was developed to address the clinical challenges of complex bone defects. The multifunctional construct was fabricated via in situ polymerization combined with a gas foaming technique, creating hierarchical porous architectures that mimic the native bone extracellular matrix. By incorporating polydopamine (PDA)-modified amorphous calcium phosphate (CA) into poly(propylene glycol) (PPG)- and poly(ԑ-caprolactone) (PCL)-based polyurethane (PU). The obtained scaffolds achieved osteoinductive potential for bone tissue engineering. The surface PDA modification of CA enabled efficient photothermal shape conversion under near-infrared (NIR) irradiation, facilitating non-invasive remote control of localized hyperthermia. The optimized scaffolds exhibited interconnected porosity (approximately 70%) with osteoconductive pore channels (200–500 μm), resulting in good osteoinduction in cell culture, and precise shape-memory recovery at physiological temperatures (~40 °C) under NIR for minimally invasive delivery. The synergistic effect of osteogenesis promotion and photothermal transition demonstrated this programmable scaffold as a promising solution for integrated minimally invasive bone repair and defect reconstruction. Full article

Dehydrated human-derived amnion–chorion membranes (ACM), known for their bioactive composition of growth factors and cytokines, have demonstrated potential as a bioactive scaffold in regenerative medicine; however, their clinical application in regenerative endodontic procedures (REPs) remains unexplored. This retrospective study aimed to evaluate the clinical and radiographic outcomes of REPs using ACM compared to collagen matrices (CM) in immature necrotic permanent teeth. Forty-one immature necrotic teeth from 38 patients (mean age: 14.68 ± 7.43 years) were treated with REPs using either ACM (n = 21) or CM (n = 20) scaffolds over a mean follow-up period of 23.23 months. Outcomes assessed included survival, success, root development measured by radiographic root area (RRA), and pulp sensibility. Independent t-tests compared outcomes between groups, while Cox regression and generalized linear models identified predictors of treatment outcomes. Overall survival and success rates were 87.8% and 82.9%, respectively. ACM-treated teeth achieved 90.5% survival and 85.7% success rates, while CM-treated teeth demonstrated 85.0% survival and 80.0% success rates, with no statistically significant differences between groups (p > 0.05). Root development occurred in 85.4% of cases overall, with significant RRA increases of 13.89 ± 13.95% for ACM and 11.24 ± 11.21% for CM (p < 0.05 within each group). Pulp sensibility recovery was observed in 51.2% of treated teeth overall, with 42.9% for ACM-treated teeth and 55.0% for CM-treated teeth (p > 0.05). Notably, ACM-treated teeth demonstrated earlier sensibility recovery compared to those of CM-treated teeth. Age was identified as a significant negative predictor of root development outcomes (p < 0.05). This clinical study demonstrates that both ACM and CM are clinically effective scaffolds for REPs, achieving high survival rates and promoting root development in immature necrotic teeth. While overall success rates were comparable, ACM showed faster sensibility recovery, suggesting potential biological advantages for enhanced tissue regeneration and earlier functional recovery. Full article

Bone tissue engineering has gained attention recently as a method for regenerating bone critical-size defects. This work aims to synthesize a hydrogel based on gelatin, di-amine polyethylene glycol, Polyethylene Glycol-Polypropylene Glycol-Polyethylene glycol, using genipin as a cross-linker and adding hydroxyapatite as a ceramic insert that can be used as a cellular scaffold in bone tissue engineering. Characterization was performed using Fourier transform infrared spectroscopy, identifying the leading absorption bands to verify that the hydrogels cross-linked correctly. The hydrogels with elastic modules and resistances that best adapted to the values reported for the mandibular trabecular bone were identified through mechanical tests. Using scanning electron microscopy, the presence of hydroxyapatite in the hydrogels was verified. The hydrogels with the best results were selected to carry out the biological assays. The cell viability assay verified that the osteoblastic cells proliferated better in the hydroxyapatite scaffolds, and the composite hydrogel induced osteoblast differentiation from undifferentiated mesenchymal stem cells. Hydrogels loaded with hydroxyapatite proved to be a promising biomaterial with potential application in bone regeneration. Full article

The urgent need to mitigate rising global CO₂ emissions demands the development of efficient carbon capture technologies. This study addresses the persistent challenge of sintering-induced performance degradation in CaO-based sorbents during high-temperature CO₂ capture. A novel solvent/nonsolvent synthetic strategy to fabricate CaO/CaAl-layered double oxide (LDO) composites was developed, where CaAl-LDO serves as a nanostructural stabilizer. The CaAl-LDO precursor enables atomic-level dispersion of components, which upon calcination forms a Ca₁₂Al₁₄O₃₃ “rigid scaffold” that spatially confines CaO nanoparticles and effectively mitigates sintering. Thermogravimetric analysis results demonstrate exceptional cyclic stability; the composite achieves an initial CO₂ uptake of 14.5 mmol/g (81.5% of theoretical capacity) and retains 87% of its capacity after 30 cycles. This performance significantly outperforms pure CaO and CaO/MgAl-LDO composites. Physicochemical characterization confirms that structural confinement preserves mesoporous channels, ensuring efficient CO₂ diffusion. This work establishes a scalable, instrumentally simple route to high-performance sorbents, offering an efficient solution for carbon capture in energy-intensive industries such as power generation and steel manufacturing. Full article

Nanotechnologies bring a rapid paradigm shift in hard and soft bone tissue regeneration (BTR) through unprecedented control over the nanoscale structures and chemistry of biocompatible materials to regenerate the intricate architecture and functional adaptability of bone. This review focuses on the transformative analyses and prospects of current and next-generation nanomaterials in designing bioactive bone scaffolds, emphasizing hierarchical architecture, mechanical resilience, and regenerative precision. Mainly, this review elucidated the innovative findings, new capabilities, unmet challenges, and possible future opportunities associated with biocompatible inorganic ceramics (e.g., phosphates, metallic oxides) and the United States Food and Drug Administration (USFDA) approved synthetic polymers, including their nanoscale structures. Furthermore, this review demonstrates the newly available approaches for achieving customized standard porosity, mechanical strengths, and accelerated bioactivity to construct an optimized nanomaterial-oriented scaffold. Numerous strategies including three-dimensional bioprinting, electro-spinning techniques and meticulous nanomaterials (NMs) fabrication are well established to achieve radical scientific precision in BTR engineering. The contemporary research is unceasingly decoding the pathways for spatial and temporal release of osteoinductive agents to enhance targeted therapy and prompt healing processes. Additionally, successful material design and integration of an osteoinductive and osteoconductive agents with the blend of contemporary technologies will bring radical success in this field. Furthermore, machine learning (ML) and artificial intelligence (AI) can further decode the current complexities of material design for BTR, notwithstanding the fact that these methods call for an in-depth understanding of bone composition, relationships and impacts on biochemical processes, distribution of stem cells on the matrix, and functionalization strategies of NMs for better scaffold development. Overall, this review integrated important technological progress with ethical considerations, aiming for a future where nanotechnology-facilitated bone regeneration is boosted by enhanced functionality, safety, inclusivity, and long-term environmental responsibility. Therefore, the assimilation of a specialized research design, while upholding ethical standards, will elucidate the challenge and questions we are presently encountering. Full article

Three-dimensional printed polycaprolactone (PCL) tissue engineering scaffolds have drawn increasing interest from the medical industry due to their excellent biocompatibility and biodegradability, yet PCL’s poor mechanical performance has limited their applications. This study introduces a biocompatible and biodegradable polylactic acid (PLA) fiber reinforced PCL (PLA/PCL) composite as the filament for 3D printed scaffolds to significantly enhance their mechanical performance: Special-made PLA short fiber mat was infused with PCL matrix and rolled into PLA/PCL filaments through a “Vacuum Assisted Resin Infusion” (VARI) process. The investigation revealed that the PLA fibers are highly oriented along the printing direction when using this filament for 3D printing due to the unique microstructure formed during the VARI process. At the same PLA fiber content, the percentage increase in Young’s modulus of the 3D printed strands using the filaments produced by the VARI process is 127.6% higher than the 3D printed strands using the filaments produced by the conventional melt blending process. The 3D printed tissue engineering scaffolds using the PLA/PCL composite filament with 11 wt% PLA fiber content also achieved an exceptional 84.2% and 143.3% increase in peak load and stiffness compared to the neat PCL counterpart. Full article