Journal of Functional Biomaterials最新文献

Allomelanin is a natural class of melanin found mainly in fungi and derived from nitrogen-free precursors such as 1,8-dihydroxynaphthalene (1,8-DHN). Despite its biological relevance, allomelanin remains significantly less explored than other synthetic melanin analogs, particularly compared to polydopamine, a synthetic analog of eumelanin. In this review, we provide a comprehensive overview of current knowledge on allomelanin, summarizing the main methods used to characterize its molecular structure, morphology, and chemical functionalities. We also present its emerging applications, ranging from human health to materials science, highlighting how its optical characteristics, ability to modulate redox processes, and antioxidant properties support its growing technological interest. Finally, we describe the natural presence and biological role of allomelanin, highlighting how knowledge of its biosynthetic processes and functions in nature can guide more effective strategies for the design and optimization of new allomelanin materials.

Cutaneous leishmaniasis is a zoonotic disease caused by Leishmania parasites and leads to chronic, non-healing skin lesions. Although current drugs can control the disease, their use is limited by systemic side effects, low efficacy, and inadequate lesion penetration. Therefore, innovative local delivery systems are required to enhance drug penetration and reduce systemic toxicity. To address these challenges, silver nanoparticles (AgNPs) were synthesized using propolis extract through a green synthesis approach, and a tri-layer wound dressing composed of polyvinyl alcohol and gelatin containing synthesized AgNPs and Glucantime was fabricated by electrospinning. Characterization (SEM-EDX, FTIR, TGA) confirmed uniform morphology, chemical structure, and thermal stability; the wound dressing exhibited hydrophilicity, antioxidant activity, and biphasic release. Biological evaluations against Leishmania tropica demonstrated significant antiparasitic activity. Promastigote viability decreased from 76.3% in neat fibers to 31.6% in nanofibers containing AgNPs and 7.9% in tri-layer nanofibers containing both AgNPs and Glucantime. Similarly, the amastigote infection index dropped from 410 in controls to 250 in neat nanofibers, 204 in AgNPs-containing nanofibers, and 22 in tri-layer nanofibers containing AgNPs and Glucantime. The tri-layer nanofibers demonstrated enhanced antileishmanial activity over AgNPs-containing fibers, confirming synergistic efficacy. All nanofibers were biocompatible, supporting their use as a safe platform for cutaneous leishmaniasis treatment.

Small-diameter synthetic grafts often fail from thrombosis, intimal hyperplasia, and compliance mismatch, highlighting the need for alternatives that better support endothelialization and remodeling. Here, we evaluated multilayer plant-based vascular grafts fabricated from decellularized leatherleaf viburnum reinforced with cross-linked gelatin, seeded with vascular smooth muscle cells and endothelial cells, and conditioned in a perfusion bioreactor to mimic physiological shear stress. Pre-implant assays confirmed effective decellularization, low residual detergent, and mechanical integrity suitable for surgical handling. In a rat abdominal aorta interposition model, plant-based grafts remained patent at 1, 4, and 24 weeks and showed higher survival than silicone controls. Ultrasound imaging demonstrated flow patterns and resistance indices similar to native vessels, and plant-based grafts maintained significantly higher endothelial cell coverage than silicone controls, reaching native-like density by 24 weeks. Histology and biochemical assays showed early collagen and elastin coverage comparable to native aorta and increased collagen by 24 weeks. Scanning electron microscopy showed smooth luminal surfaces with minimal thrombus formation, contrasting with the rougher, thrombus-prone surfaces of silicone grafts. These findings indicate that plant-based grafts support endothelialization, maintain long-term patency, and undergo favorable remodeling in vivo, supporting their potential as a biomimetic alternative for small-diameter arterial repair.

Recent advances in biomaterials, immunomodulation, stem cell therapy, and biofabrication are reshaping maxillofacial surgery, shifting reconstruction paradigms toward biologically integrated and patient-specific tissue regeneration. This review provides a comprehensive synthesis of current and emerging strategies for bone and soft-tissue regeneration in the craniofacial region, with particular emphasis on bioactive ceramics, biodegradable polymers, hybrid composites, and stimuli-responsive smart materials. We further examine translational technologies such as extracellular vesicles, decellularized extracellular matrices, organoids, and 3D bioprinting, highlighting key challenges such as bioink standardization, perfusion limitations, and regulatory classification. Maxillofacial surgery is positioned for a paradigm shift toward personalized, biologically active, and clinically scalable regenerative solutions.

Objective: To evaluate the clinical success outcomes and risk factors associated with dental implants placed with simultaneous bone augmentation in a large-scale, real-world cohort.

Methods: A retrospective analysis was conducted on 158,824 implants, including 45,715 Dental Bone Grafts, placed between 2014 and 2022 within a national healthcare network. Multivariate Generalized Estimating Equations were utilized to assess the impact of demographic, anatomical, and procedural variables on implant failure.

Results: The augmented cohort demonstrated a high clinical success rate of 97.83% (2.17% failure), statistically comparable to the general implant population. Failures were predominantly early (<1 year), accounting for 70% of losses. Significant independent risk factors included immediate implant placement (3.08% failure vs. 2.07% for delayed), male gender, and maxillary location. Notably, low socioeconomic status (SES) emerged as a significant predictor, with a failure rate of 3.07% compared to 2.06% in high-SES groups.

Conclusions: Simultaneous bone augmentation is a predictable modality that does not inherently increase implant failure risk, supporting the stabilization hypothesis. However, failure is modulated by specific variables. The identification of lower SES, male gender, and immediate placement as significant risk indicators highlights the necessity for personalized risk assessment and targeted protocols to optimize outcomes in augmented sites.

Skin cancer is among the most common malignancies worldwide, posing a significant societal burden due to its increasing incidence and its limited responsiveness to conventional topical therapies. Treatment is challenged by the presence of the skin barrier which restricts drug penetration. This review discusses the structural and physiological challenges of topical delivery and summarizes efforts to develop functional biomaterials to enhance skin drug penetration. Important aspects to consider when developing formulation strategies, such as drug properties and release mechanisms, are discussed alongside current limitations and future perspectives.

Three-dimensional biomaterial scaffolds with controlled geometry and surface nanoarchitecture are essential for advancing polymer processing strategies in tissue engineering. Conventional electrospinning generates nanofibrous structures but has limited ability to reproduce defined three-dimensional shapes or achieve high pattern fidelity. This study aimed to develop a scalable processing method for producing biodegradable scaffolds with precisely controlled microstructure and geometry using phase separation-assisted electrospray. Poly (lactic acid) microcapsules with tunable diameters and porous nanofibrous surfaces were fabricated under controlled humidity and deposited onto conductive molds to obtain two- and three-dimensional scaffold shapes. The manufacturing process required only simple electrospray equipment and static molds, without mechanically complex collectors or moving stages. The resulting scaffolds replicated mold features with resolutions down to 200 μm and achieved thickness up to 600 μm. The nanofibrous microcapsule surfaces supported strong adhesion and metabolic activity of HepG2 cells, while cellular penetration into deeper scaffold regions remained limited to approximately 80 μm. These findings indicate that electrospray-mediated microcapsule deposition is a practical polymer-processing approach that integrates nanofibrous surface formation with mold-defined shaping, offering a reproducible and scalable method for fabricating structurally precise and biologically compatible three-dimensional scaffolds.

Periodontal disease represents a major global concern characterized by chronic biofilm-driven inflammation, excessive oxidative stress, progressive tissue destruction, and impaired regenerative capacity. Beyond conventional antimicrobial approaches, recent progress has shifted toward host-directed and regenerative therapeutic strategies aimed at restoring both oral function and tissue homeostasis. This review consolidates current developments in nanobiotechnology-based materials that modulate immune responses, scavenge reactive oxygen species, and promote angiogenesis and osteogenesis, thereby facilitating the effective regeneration of dental and periodontal tissues. Emphasis is placed on bioresponsive hydrogels, bioactive scaffolds, and gas-releasing platforms that integrate therapeutic regulation with tissue repair. The discussion further highlights key advances in polymeric and inorganic biomaterials designed to balance antibacterial action with cellular compatibility and regenerative potential. By linking pathophysiological mechanisms with material-guided healing processes, this review provides a comprehensive perspective on emerging nanobiotechnological solutions that bridge patho-therapeutics with regenerative and clinical dentistry.

Peptide-based biomaterials have emerged as versatile tools for pharmaceutical drug delivery due to their biocompatibility and tunable sequences, yet a comprehensive overview of their categories, mechanisms, and optimization strategies remains lacking to guide clinical translation. This review systematically collates advances in peptide-based biomaterials, covering peptide excipients (cell penetrating peptides, tight junction modulating peptides, and peptide surfactants/stabilizers), self-assembling peptides (peptide-based nanospheres, cyclic peptide nanotubes, nanovesicles and micelles, peptide-based hydrogels and depots), and peptide linkers (for antibody drug-conjugates, peptide drug-conjugates, and prodrugs). We also dissect sequence-based optimization strategies, including rational design and biophysical optimization (cyclization, stapling, D-amino acid incorporation), functional motif integration, and combinatorial discovery with AI assistance, with examples spanning marketed drugs and research-stage candidates. The review reveals that cell-penetrating peptides enable efficient intracellular payload delivery via direct penetration or endocytosis; self-assembling peptides form diverse nanostructures for controlled release; and peptide linkers achieve site-specific drug release by responding to tumor-associated enzymes or pH cues, while sequence optimization enhances stability and targeting. Peptide-based biomaterials offer precise, biocompatible and tunable solutions for drug delivery, future advancements relying on AI-driven design and multi-functional modification will accelerate their transition from basic research to clinical application.

Neodymium-doped bioactive wollastonite-tricalcium phosphate (W-TCP:Nd) coatings were fabricated by combining dip-coating and laser floating zone (LFZ) techniques to investigate the dependence of optical emission on polarization. Structural and spectroscopic analyses were performed on both longitudinal and transversal sections of the coating to assess the effects of directional solidification on luminescence and vibrational behavior. Micro-Raman spectroscopy revealed that the coating exhibited sharp, well-defined peaks compared to the W-TCP:Nd glass, confirming its glass-ceramic nature. New Raman modes appeared in the longitudinal section, accompanied by red and blue shifts in some bands relative to the transversal section, suggesting the presence of anisotropic stress and orientation-dependent crystal growth. Optical emission measurements showed that while the ⁴F_3/2→⁴I_11/2 transition near 1060 nm was nearly polarization independent, the ⁴F_3/2→⁴I_9/2 transition around 870-900 nm exhibited strong polarization dependence with notable Stark splitting. The relative intensity and spectral position of the Stark components varied systematically with the rotation of the emission polarization. These findings demonstrate that directional solidification induces polarization-dependent optical behavior, indicating potential applications for polarization-sensitive optical tracking and sensing in bioactive implant coatings.