Journal of biomedical materials research. Part B, Applied biomaterials最新文献

Developing innovative wound dressing biomaterials is vital for proper wound care management. The synergy of medicinal plant secondary metabolites and nanotechnology presents a promising approach to promoting wound healing by facilitating a quicker and more effective healing progression. In this study, polycaprolactone (PCL) in combination with gelatin (Gel) nanofibrous membranes containing 7-hydroxy-4-methyl coumarin (coumarin)-loaded layered double hydroxide (LDH) nanohybrids were fabricated via electrospinning. LDH/coumarin nanohybrids were prepared using the coprecipitation method. LDH/coumarin was added to the PCL-Gel solution at different concentrations. Scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX) were used to characterize the nanofibers. The nanofibers were evaluated for their mechanical, cytocompatibility, and in vivo properties. The results demonstrated that LDH improved the mechanical properties of PCL-Gel nanofibers, and the highest tensile strength was achieved in PCL-Gel containing 1 wt% LDH (3.12 MPa). Moreover, the nanofibers exhibited no cytotoxicity against the L-929 mouse fibroblast cell line (viability was greater than or equal to 70%). The animal study results revealed that the rate of wound healing was faster in nanofibers containing LDH/coumarin, covering 77.5% of the wound area, and the quality of wound healing was significantly increased in guinea pigs' skin wound closure. The synergistic effect of PCL-Gel-LDH/coumarin (1%) could provide valuable insights and implications for promoting its application in wound dressings.

Considering the scarcity of medications with a wide range of therapeutic effects for the endodontic treatment, this study aimed to synthesize two morin (Mo) derivatives and test their cytotoxicity and effect on multispecies biofilm, in solution and loaded in nanoemulsions (NE). Minimum inhibitory and bactericidal concentration (MIC/MBC) of Mo, penta-acetylated Mo (Ac-Mo), Mo complexed with strontium (Sr-Mo) and control chlorhexidine digluconate (CHX) were determined against Enteroccocus faecalis, Actinomyces israelii, Streptococcus mutans, Lactobacillus casei, Fusobacterium nucleatum. NE were physiochemically characterized by analysis of droplet size and polydispersity index using dynamic light scattering, by determination of zeta potential, by Nanoparticle Tracking Analysis, and by Fourier Transform Infrared Spectroscopy analysis. NE containing Mo, its derivatives (at 2 mg/mL), and CHX (at 0.5 mg/mL) were evaluated against multispecies biofilms by bacterial counts, scanning electron microscopy, and confocal microscopy. The cytotoxicity of the compounds and NE was also determined in fibroblasts (L929) using resazurin assays. The data were statistically evaluated (p < 0.05). All compounds were considered potentially bactericidal against the bacteria tested. The values of MBC ranged from 0.25 to 1 mg/mL. Metabolic activity of fibroblasts was higher than 70% after treatment with compounds up to 0.25 mg/mL. Data from physiochemical characterization confirmed the successful formation of stable, uniformly dispersed nanoemulsion suitable for drug delivery applications. The highest bacterial reduction in multispecies biofilms was observed in NE + Ac-Mo, followed by NE + Mo, CHX, and NE + Sr-Mo groups. All NE diluted at 12.5% did not affect fibroblast metabolism after 24 h of treatment. Although in different concentrations, morin and its derivatives, either alone or loaded in nanoemulsions, were bactericidal (up to 1 mg/mL) and demonstrated antibiofilm effect (at 2 mg/mL). They also were cytocompatible at lower concentrations (0.25 mg/mL). Nanoemulsion containing penta-acetylated morin could be an alternative intracanal medication for reducing residual bacteria between short-term clinical appointments in endodontic approaches.

Tissue-engineering scaffolds require interconnected porous networks to support cell infiltration, nutrient diffusion, and waste removal. Conventional methods to introduce porosity—such as particulate leaching, gas foaming, and freeze-drying—can leave cytotoxic residues. We propose a scalable, cytocompatible approach to tune hydrogel porosity using lipid-shelled gas microbubbles as a transient porogen. In this study, we demonstrate that lipid-shelled microbubbles can be incorporated into alginate, poly(ethylene glycol) diacrylate (PEGDA), or gelatin methacrylate (GelMA) precursors, and subsequently expanded post-gelation with mild heat or vacuum to yield controlled porosity. In alginate fibers, the vacuum expansion of embedded microbubbles increased the swelling capacity by approximately 74% relative to nonporous control, without reducing compressive strength. Porous PEGDA hydrogels showed faster degradation (approximately 40% reduction in degradation time) and a lower compressive modulus compared to the dense PEGDA control, reflecting a tunable trade-off between porosity and stiffness. Unlike traditional porogen-based or 3D-printing techniques, this microbubble method requires no toxic additives or specialized equipment and is compatible with both ionic (alginate) and photo-crosslinked (PEGDA, GelMA) systems. We further demonstrate integration of this approach with a microfluidic fiber production platform. We validate that porosity modulation via microbubbles does not adversely affect the viability of mesenchymal stem cells on GelMA hydrogels. Overall, this work establishes a broadly applicable and easily scaled strategy in which porosity can be tuned post-gelation with simple triggers (heat or vacuum), enabling application-specific control of nutrient transport, degradation, and mechanics across multiple biomaterials.

Tracheal defects caused by trauma, malignancy, congenital anomalies, or prolonged intubation remain a significant clinical challenge, particularly for long-segment replacements where conventional solutions such as autologous tissue grafts, allografts, and synthetic implants have shown limited long-term success. Tissue-engineered tracheas (TETs) have emerged as a promising alternative by integrating advances in scaffold design, fabrication techniques, and biological augmentation. Recent progress in scaffold materials, including decellularized natural matrices, synthetic polymers, and hybrid composites, has led to the development of constructs that better mimic the structural and functional properties of the native trachea. Fabrication techniques such as 3D printing, electrospinning, and cell sheet engineering have enabled the production of anatomically precise and patient-specific grafts. In parallel, biological strategies aimed at promoting vascularization, accelerating epithelialization, and modulating immune responses have significantly improved graft integration and long-term functionality. Despite these advances, the clinical translation of TETs remains hindered by challenges related to achieving adequate vascularization, complete epithelialization, and immune modulation. Additionally, regulatory approval requires rigorous preclinical validation, standardized manufacturing protocols, and long-term safety assessments to ensure consistent clinical outcomes. As these challenges are addressed through ongoing research, TETs hold the potential to revolutionize the treatment of long-segment tracheal defects by providing functional, durable, and biologically integrated airway replacements.

Chronic wounds pose a significant health challenge that affects millions of people worldwide. Traditional treatments, such as antibiotics, have limitations, including the development of antibiotic resistance. Antimicrobial peptides (AMPs) are gaining attention due to their broad-spectrum antimicrobial activity, including against multidrug-resistant strains. TetraF2W-RR, a specific AMP, has shown promise in combating various bacteria, particularly when incorporated into wound dressings. Another emerging antimicrobial approach is photodynamic therapy (PDT), which utilizes photosensitizers (PS), such as chlorin e6 (Ce6), activated by light to destroy bacteria without inducing resistance. Ce6 offers advantages such as rapid photosensitization, selective accumulation in target areas, and minimal side effects, making it a favorable candidate for PDT in wound treatment. Furthermore, combining AMPs with PDT offers a combined approach for enhanced antibacterial activity. Although hydrogel dressings, particularly GelMA, provide an ideal environment for wound healing, GelMA lacks intrinsic antimicrobial properties and can promote bacterial growth. Therefore, combining GelMA with antimicrobial strategies is crucial. Herein, to investigate the influence of different strategies on antimicrobial efficiency, two distinct approaches were developed for the functionalization of GelMA with AMP and Ce6. This is the first comparative study of different AMP and PS conjugation strategies for enhancing PDT on hydrogels. In the first approach, the Ce6@AMP conjugate was immobilized onto GelMA (GelMA/Ce6@AMP). In the second approach, AMP and Ce6 were separately conjugated to GelMA via EDC/NHS chemistry (GelMA/AMP/Ce6). GelMA/Ce6@AMP hydrogels significantly lost their antibacterial activity, whereas GelMA/AMP/Ce6 hydrogels maintained strong antimicrobial and anti-biofilm effects, which clearly demonstrates the impact of conjugation strategy on antibacterial performance.

Exosomes, nanoscale extracellular vesicles, have garnered substantial interest in biomedical research owing to their critical roles in intercellular communication, diagnostics, and regenerative therapeutics. Among biomolecules investigated in regenerative medicine, exosomes are one of the most intensively researched. While no clinical trials have yet been conducted to assess their regenerative efficacy in human dental applications, a rapidly growing body of preclinical research highlights their therapeutic potential in oral and maxillofacial regeneration. Dental tissue-derived exosomes, most notably from dental pulp stem cells, periodontal ligament stem cells, gingival fibroblasts, and stem cells from exfoliated deciduous teeth, have shown the ability to promote regeneration of bone, the periodontal ligament and other supporting tissues. Moreover, these exosomes have demonstrated potential roles in modulating orthodontic tooth movement and alleviating temporomandibular joint disorders. Preclinical studies included in this review consistently reported improved bone regeneration outcomes, such as increased bone volume, mineralization, and osteogenic marker expression following exosome application. Importantly, exosomes have also exhibited potent immunomodulatory effects, notably through inhibition of inflammation in bone defects and periodontitis models. The therapeutic versatility of exosomes is further reflected in their application across several fields of dentistry, such as periodontitis therapy, pulp regeneration, alveolar bone regeneration, and immune regulation. The majority of the studies highlighted the anti-inflammatory, pro-angiogenic, and osteoinductive features of exosomes, derived from diverse cellular sources. These promising preclinical outcomes collectively indicate that exosome-based therapies hold strong potential for translation into clinical dental practice, offering a novel, cell-free, and biologically targeted strategy to craniofacial tissue regeneration.