Journal of Biomaterials Applications最新文献

The most common formulation for treating ocular conditions is topical eyedrops, despite their well-documented inefficiency. In this study, mucoadhesive nano-micelles were developed to overcome the poor efficacy of topical eyedrops in the treatment of dry eye disease. The micelles contained a pre-activated thiomer capable of releasing mucolytic N-acetylcysteine upon covalent disulfide exchange with the natural mucus layer which covers the surface of the eye. The micelles, approximately 70 nm in diameter, were shown to be mucoadhesive through zeta potential analysis. The critical micelle concentration was determined to be 217 mg/L using the pyrene fluorescence method. The core of the micelles was loaded with cyclosporine A, displaying a greater than 90% entrapment efficiency, and yielding sustained release of approximately 57% over 10 days. The cellular response to the micelles was tested with human corneal epithelial cells by MTT assay and Live/Dead staining. It was found that lower concentrations of the amphiphilic polymer resulted in greater cellular viability and in all cases, viability increased from 24 to 48 h following treatment. Overall, these mucoadhesive systems have potential to provide more efficacious treatment of anterior segment ocular conditions.

In sol-gel glass chemistry, the pH of the sol directly influences the rate of the hydrolysis and condensation reactions, leading to changes in the glass's structural properties and potentially altering its function as a biomaterial. This research used various acidic pH values, 2, 3, 3.65, 5, and 5.65, to create sol-gel bioactive glass with a 45SiO₂-14.5NaO₂-14.5CaO-6P₂O₅-10ZnO-5CuO-5CoO mol% composition. A pH of 2 allowed for increased surface area, 26.23 m²/g, and cumulative surface area of pores, 34.78 m²/g, compared to the other pH values used. Raman spectroscopy highlighted variances in the intensity of Q² and Q³ species, with a pH of 2 and 3.65 having a higher intensity of Q³ species. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) revealed that the concentration of Cu²⁺ ions released from the glass network in simulated body fluid (SBF) was the highest after 1000 h of incubation for the pH 3.65 glass, 100 mg/L, which translated to the most significant inhibition of E. coli after 48 h of contact. Elemental, thermal, and structural analysis using energy dispersive X-ray spectroscopy, differential thermal analysis, Fourier-Transform Infrared Spectroscopy, and X-ray diffraction was also performed, with no discernible relationship found between changing the pH of the sol used to synthesize these glasses.

High bone-localized concentrations of antimicrobial agents are necessary for the long-term effective treatment of chronic osteomyelitis, particularly in cases of severe infection and bone loss. This study addressed infection control and bone regeneration simultaneously using hydroxyapatite and natural biopolymers. Moxifloxacin hydrochloride was delivered via composite scaffolds produced from polyvinyl alcohol/gelatin and hydroxyapatite with potential applications in osteomyelitis treatment and bone tissue engineering. The composite scaffolds exhibited a well-defined porous architecture, characterised by macropores (≥100 µm) and micropores (≤20 µm), facilitating cellular infiltration and drug loading. Biomineralization and cell culture assays were used to evaluate the scaffold's bioactivity and biocompatibility. Analyses of mineralized scaffolds using Fourier-transform infrared spectroscopy and scanning electron microscopy revealed HA nucleation on the scaffold's surface after immersion in simulated bodily fluid for varied time points. Protein adsorption and haemolysis tests were conducted to confirm the blood compatibility of scaffolds. Cell culture studies using human mesenchymal stem cells indicated non-cytotoxicity and robust cell adhesion. These findings suggest the potential suitability of these scaffolds for future clinical applications in the treatment of chronic osteomyelitis and bone regeneration.

Cartilage tissue engineering (CTE) provides a promising solution for osteoarthritis, with scaffold materials playing a crucial role in supporting cell activity. There have been many studies of various scaffold materials, yet few studies have directly compared the effects of marine collagen fibrils on chondrocyte chondrogenesis. This study determined the effects of types I and II collagen fibrils derived from sturgeon on ATDC5 cell chondrogenesis. The CCK-8 results showed that type I fibrils promoted ATDC5 cell proliferation more effectively than type II fibrils. Alcian Blue staining results revealed that cells cultured on type II fibrils secreted more proteoglycans than those on type I fibrils. The mRNA expression analysis indicated that type I fibrils initiated cell differentiation at an early stage, but simultaneously induced premature hypertrophy, suggesting that type I fibrils were difficult to maintain the chondrogenic phenotype in long-term culture. In contrast, type II fibrils generally enhanced the expression of chondrogenic genes, but also upregulated matrix metalloproteinase collagen-degrading enzymes, thereby accelerating the matrix degradation process. These findings suggested the potential of sturgeon collagen as a CTE scaffold material, and identified the different effects of types I and II collagen fibrils on ATDC5 cell chondrogenesis, to provide a theoretical foundation for selecting suitable scaffold biomaterials, based on different needs, while also providing new insights for the application of marine collagen.

In skin tissue engineering, the cross-linking of wound dressings is a critical step as it enhances mechanical strength. This improved strength regulates the release of incorporated components and determines the dressing's replacement schedule. Therefore, due to the lack of comparative knowledge for the cross-linking of carboxymethyl chitosan, gelatin, and polyvinyl alcohol (CMCs-Gel-PVA) wound dressings, this study was designed a systematic comparison of five distinct strategies: chemical cross-linkers-glutaraldehyde (GLU), EDC/NHS, citric acid (CA), and succinic acid (SA)-alongside a physical freeze-thaw method. Cross-linked wound dressings were fabricated and systematically characterized in terms of surface morphology (SEM), chemical bonding (FTIR), mechanical strength, porosity, biodegradability, fluid absorption, blood compatibility, cytotoxicity, and anti-inflammatory activity. The scaffolds exhibited interconnected pores ranging from 32.07 to 89.12 µm. The non-cross-linked sample showed higher porosity, liquid absorption, and degradation rate (90.33 ± 5.17%), which was attributed to its lower mechanical strength. All samples demonstrated good biocompatibility with no significant cytotoxic effects on 3T3 fibroblasts. Tensile strength values ranged from 0.15 to 1.92 MPa. Glutaraldehyde-crosslinked scaffolds displayed superior mechanical properties suitable for load-bearing wound applications, despite a slight reduction in cell viability (92.59 ± 3.19%), which remained above the accepted clinical biocompatibility threshold. These scaffolds also showed enhanced coagulation activity, whereas citric acid-crosslinked samples exhibited anticoagulant behavior and superior anti-inflammatory potential. In conclusion, this comparative study demonstrates that the choice of cross-linker dictates key functional properties of CMCs-Gel-PVA scaffolds, allowing for the strategic tuning of mechanical strength, degradation rate, hemostatic activity, and anti-inflammatory potential. These tailored in vitro characteristics support their further investigation as candidate materials for advanced wound dressing applications. The successful in vivo validation of these findings remains a critical next step to fully ascertain the translational potential of this biomaterial platform.

Conventional calcium sulfate bone cements suffer from rapid degradation, poor anti-washout property, and inadequate bioactivity. To overcome these limitations, we developed an injectable bone cement based on a novel ternary synergistic system of Sr-doped alginate-phosphate (SA/Sr/PO₄^3-) and hydrothermally synthesized α-calcium sulfate hemihydrate (α-CSH). This design leverages the rapid physical crosslinking between Ca²⁺ from α-CSH and the guluronic acid/mannuronic acid blocks of sodium alginate, resulting in a reinforced network with enhanced initial anti-washout property and a wet compressive strength of 2-12 MPa. Simultaneously, the alginate matrix induces the in situ mineralization of Ca²⁺ and PO₄^3- ions, forming a calcium-deficient hydroxyapatite (CDHA) precursor that decelerates the degradation rate (18% in PBS over 60 days) to match new bone formation. In addition, strontium ions (Sr²⁺) sustainably released from the material promote in vitro osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). This work presents a novel composite cement that successfully integrates injectability, robust mechanical properties, controllable degradation, and osteoinductive capability.

Directed differentiation of bone marrow mesenchymal stem cells (BMSCs) provides a promising route for neural trauma repair, yet faces challenges in establishing an optimal microenvironment for efficient neuronal maturation. In this work, a synergistic bio-electroactive platform was established to specifically induce neuronal differentiation from BMSCs by coupling spatially oriented, conductive polycaprolactone/reduced graphene oxide (PCL/rGO) nanofibrous scaffolds with exogenous electrical stimulation (ES). Through the integration of topological guidance and rGO-enhanced conductivity, significant cytoskeletal remodeling and cell proliferation were realized. Notably, the synergistic stimulation robustly drove the lineage commitment toward mature neurons, evidenced by the distinct neuron-like morphology (spherical-elliptical somas and elongated processes) and the marked upregulation of neural-specific markers (Tuj1 and MAP2) at both transcriptional and translational levels. The PCL/rGO + ES group achieved the highest differentiation efficiency, outperforming PCL/rGO group with an approximate 2.29-fold increase in MAP2 expression, confirming the superior synergy of the dual-signal stimulation. This bio-electroactive strategy effectively creates a conducive microenvironment for mature neuronal differentiation and offers a facile, promising perspective for the treatment of neural trauma.

Magnesium phosphate cement (MPC) has emerged as a promising biomaterial in preclinical studies for orthopedic applications, particularly in bone defect repair, due to its rapid setting properties and high mechanical strength. However, excessive MgO in MPCs accelerates the setting and heat release, which necessitates an increased liquid-to-powder ratio (LPR) that compromises strength, ultimately making it difficult to reconcile the performance metrics of processability, heat release, and mechanical strength. In this study, trimagnesium phosphate-magnesium phosphate cement (TM-MPC) was developed by replacing excess MgO with chemically stable trimagnesium phosphate (Mg₃(PO₄)₂, TMP) at a low LPR (down to 0.20 mL/g, PLR = 5 g/mL). This strategy resulted in the formation of cement material system with suitable setting time (10-12 min), low curing temperature (<47°C), remarkable early compressive strength (131.25 ± 29.39 MPa), near physiological pH, and good injectability (6-9 min), which could address the critical drawbacks of traditional MPCs. In vitro evaluations showed acceptable cytocompatibility in MC3T3-E1 cells. Based on heat evolution and characterization of early hydration products, reducing the LPR was found to retard initial hydration and attenuated exothermic heat release. This work provides a facile and effective strategy for engineering high-performance bone cements with improved processability, which offers a design paradigm for future MPC systems in specific biomedical applications.

This study evaluated the impact of cryoprotection temperature on the structural and biomechanical properties of gamma-irradiated human tendon allografts. Tendons were irradiated at 15 kGy or 25 kGy under three temperature conditions: -70°C, 0°C, or room temperature (RT). Structural integrity was assessed histologically and biochemically, while biomechanical properties were measured via tensile testing. Tendons irradiated at RT exhibited severe collagen disorganization and cellular loss, whereas those cryoprotected at -70°C retained aligned collagen structure with minimal disruption. Biomechanically, the -70°C groups showed significantly higher maximum stress than RT groups at both irradiation doses. Increasing irradiation dose exacerbated structural and mechanical degradation, but these effects were substantially mitigated by cryoprotection at -70°C. Thus, low-temperature protection during gamma irradiation is crucial for preserving the integrity of tendon allografts.

Peri-implantitis, a leading cause of dental implant failure, is primarily attributed to suboptimal soft tissue sealing at the implant-tissue interface, which facilitates bacterial colonization and subsequent inflammatory responses. Surface modifications on titanium can expedite good soft tissue sealing and antibacterial action. We engineer titanium surfaces with ultraviolet light-functionalized titanium dioxide nanotubes (UV-TNTs) to achieve good soft tissue sealing and antibacterial effect. Surface properties were characterized via scanning electron microscopy (SEM), surface roughness analysis, wettability assessment and methylene blue (MB) degradation. Antibacterial performance was quantified using Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) viability assays. Soft tissue integration was evaluated through fibroblast proliferation assays and immunofluorescence staining of vinculin and collagen type I. The UV-TNTs demonstrated significantly enhanced antibacterial efficacy and promoted fibroblast proliferation, adhesion and collagen deposition to improve soft tissue sealing. This surface modification strategy offers a promising approach for enhancing implant biocompatibility and long-term stability, offering useful references for advanced implant design and fabrication.