Journal of Biomaterials Applications最新文献

In this study, we report the design and fabrication of a novel biomimetic composite scaffold (PSGO) and systematically assess its potential for bone tissue engineering. The PSGO scaffold was fabricated using three-dimensional (3D) printing technology with a base matrix composed of polyethylene glycol (PEG), sodium alginate (SA), and gelatin (GEL). Obacunone-loaded polycaprolactone (OA@PM) microspheres were embedded within the scaffold to enable sustained drug release, thereby creating a structure with precise architecture and functional gradients. Comprehensive characterization of the scaffold's surface morphology, rheological properties, and drug release behavior was performed. In vitro experiments demonstrated that the PSGO scaffold significantly promoted the proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs), enhanced the expression of key osteogenic markers (RUNX-2 and OCN), and facilitated mineralized matrix formation. Furthermore, in vivo evaluation using a rat calvarial critical-size defect model-assessed via micro-computed tomography and histological analysis-confirmed its excellent osteogenic performance, with substantial new bone formation observed at both the defect margins and center. With its outstanding biocompatibility, osteoinductive capabilities, and controlled drug release properties, the PSGO scaffold offers a promising new approach for the clinical repair of large-scale bone defects.

This study explored the in vitro characteristics of a ropivacaine-loaded hydrogel designed for sustained local anesthesia, using a gelatin matrix crosslinked with different concentrations of NHS-PEG-NHS. The hydrogel was comprehensively characterized through electron microscopy, rheology, biocompatibility testing, drug release and degradation analysis, and neurotoxicity assessment. Results showed the hydrogel had excellent gelation properties, a porous 3D network structure with pore size decreasing as crosslinker concentration increased, and enhanced gel strength with higher crosslinker concentrations. As the crosslinker content increases, the network pore size decreases, enabling sustained drug release and thereby prolonging the duration of nerve block. It also demonstrated good biocompatibility, demonstrate the viability of in vivo experiments. In drug release studies, the hydrogel effectively controlled ropivacaine release, achieving a more linear profile and reducing initial burst release. This demonstrates the material's suitability for sustained-release delivery systems. Degradation studies indicated the hydrogel could persist locally for extended periods, which determine the drug's sustained release behavior within the body and consequently dictate the duration of nerve block. The neurotoxicity of local anesthetics exhibits a dose-dependent relationship. In vitro neurotoxicity experiments demonstrate that gel-loaded drugs significantly attenuate the neurotoxicity of ropivacaine, with the degree of toxicity reduction positively correlated with NHS-PEG-NHS content. This indicates that the sustained-release properties of hydrogel materials prevent the abrupt release of drugs. Sciatic nerve block was performed in mice using 0.144% w/v ropivacaine. The free-ropivacaine group exhibited a sensory block duration of 3.2 h and a motor block duration of 2.24 h. In contrast, the hydrogel formulation significantly prolonged analgesia, extending sensory blockade to approximately 13.66 h and motor blockade to 10.35 h, while inducing only minimal inflammatory responses at the injection site. The study concluded that the ropivacaine-loaded hydrogel, with its 3D crosslinked network structure, effectively modulated drug release kinetics, prolonged nerve blockade, and reduced neurotoxicity, offering a promising novel solution for local anesthetic formulation improvement.

Triamcinolone acetonide (TA) is a corticosteroid that has been widely used to treat ocular inflammation. However, due to the physicochemical properties of TA, this drug has low solubility and permeability. This study aims to improve the solubility of TA and promote better ocular absorption through solid dispersion (SD) formulation with the solvent evaporation method incorporated into in situ gel. The SD-TA was characterized by FTIR, XRD, and SEM to confirm physicochemical modifications that support enhanced solubility. The most optimal SD-TA will then be combined into an in situ gel base with a composition of poloxamer, HPMC, and HPC. The resulting in situ gel exhibited desirable physical properties, remained isotonic with lacrimal fluid, and showed no signs of toxicity. Moreover, the system achieved prolonged ocular retention, with 3.15 ± 0.15 mg of TA retained on the ocular membrane after 24 h, indicating strong potential for sustained local therapeutic effect. In conclusion, this study successfully developed a new TA delivery approach that enhances solubility, prolongs ocular residence time, and improves local anti-inflammatory efficacy. Further in vivo studies and long-term stability assessments are recommended to support clinical translation.

Frequent insulin injections remain the primary method for regulating blood glucose levels in individuals with diabetes mellitus; however, patient compliance is often poor. Due to its non-invasive nature, oral insulin delivery, exploring nanomedicine strategies, is considered a highly desirable alternative as an affordable and accessible medicine. However, the physical intestinal barriers and the harsh gastrointestinal environment provide major obstacles to reaching the best possible pharmacological bioavailability of insulin. Insulin's stability, bioavailability, and targeted administration throughout the GI tract can be improved using colloidal nanocarriers, including polymeric nanoparticles, phospholipid vesicles, and lipid-based nanoparticles. These nanocarriers mimic the physiological insulin secretion and improve the pharmacokinetics of insulin by shielding it from enzymatic degradation, facilitating controlled release, and enhancing absorption across the intestinal mucosa. Key parameters such as particle size, surface charge, zeta potential, and polymer-mucin interactions are examined concerning their effects on epithelial transport and enzymatic protection. Strategies such as PEGylation, chitosan functionalization, and bile salt incorporation are discussed with an emphasis on their interfacial engineering potential. Additionally, novel strategies such as glucose-responsive formulations, cell-penetrating peptides, and enzyme inhibitors, and innovative devices like microneedle capsules and SOMA systems have been explored to enhance oral insulin efficacy. This might not, however, be helpful for translation on its own. Another deciding aspect will be the combination of that with distinct pathways. Future perspectives and innovative approaches to enhance the therapeutic potential of nano-driven systems for oral insulin administration are also discussed in this review as an affordable and accessible medicine strategy.

This investigation examines the influence of calcium sulfate (CaS) and modified nano-hydroxyapatite (mHA) additions on the physicochemical properties, microstructural development, apatite-forming potential, and antibacterial properties of bioactive tricalcium silicate (C₃S) cement. Although C₃S cements exhibit inherent antibacterial properties, their efficacy in treating infected bone defects requires enhancement. The release kinetics of vancomycin (VANCO), an antibiotic, and the modified cements' antibacterial efficacy were systematically evaluated. The findings revealed a notable decrease in setting time from 363 to 264 min upon the integration of CaS. The composite cements demonstrated flow properties and injectability that met standard requirements, exceeding 75% at both 2 and 5 min. The modified cements noted Improved compressive strength compared to their unmodified counterparts. Furthermore, the cements promoted the formation of apatite on their surfaces when immersed in phosphate-buffered saline (PBS). Antibacterial evaluations established that VANCO released from the composites effectively impeded bacterial proliferation. These findings suggest that C₃S cement enhanced with CaS and mHA exhibits superior physicochemical characteristics and bioactivity, thereby establishing it as a promising candidate for cutting-edge bone repair materials.

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.

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.

Development of surgical sutures coated with antimicrobial agents is a promising strategy to minimize surgical site infection (SSI) and improve wound healing. The antimicrobial features of Hypericum Perforatum and biogenic silver nanoparticles (AgNPs) have arised an increasing demand for processing surgical sutures. Herein the results of the animal experiments and mechanical tests of a novel antimicrobial silk suture coated with H. perforatum extract (Hp) and biogenic AgNPs (Hp-AgNP) are reported. The study used in vivo histological, histochemical, and immunohistochemical techniques to illustrate the variations in inflammatory response, re-epithelialization, and collagenization of the coated silk sutures in a rat buccal mucosa incision model. Diameter, knot-pull tensile strength, knot security, tie-down, and needle attachment tests were carried out for evaluating the effects of the coating process on mechanical and handling properties. Histopathological and immunohistochemical evaluations revealed progressive healing in all groups, with variations in wound closure, inflammation, and cytokine expression. Hp-AgNP-coated sutures showed significant improvements in re-epithelialization and reduced TNF-α and IL-6 levels over time, highlighting their potential benefits in enhancing wound healing compared to other materials. The coating process had a remarkable effect on the mechanical and handling properties. Coated sutures exhibited higher values than control groups. Suture diameter, knot-pull tensile strength and knot security revealed the highest values for Hp-AgNP-coated suture. The Hp-AgNP coating on the silk suture significantly improves wound healing, mechanical and handling properties. This implies that it has the potential to be a feasible substitute for commercially available silk sutures in surgical interventions. (Scheme 1).

Gelatin (G) and silk fibroin (SF) are well-established as scaffold materials for bone regeneration; however, their limited binding abilities and mechanical properties often result in less-than-ideal outcomes. In this study, we sought to enhance the stability of a silk fibroin/gelatin biomimetic scaffold by introducing a tyramine bond to the gelatin and incorporating nanohydroxyapatite as a bioactive element. This innovation led to the development of a more robust silk fibroin/nano-hydroxyapatite/gelatin tyramine biomimetic scaffold (SHGT). The biomimetic scaffold was fabricated through an enzymatic reaction catalyzed by horseradish peroxidase/hydrogen peroxide (HRP/H₂O₂), which facilitated the interaction between a high concentration of silk fibroin (17%) and gelatin tyramine (GT). Additionally, nano-hydroxyapatite (nHA) was incorporated as a bioactive filler to promote bone repair. Our findings indicated that the SHG biomimetic scaffold, initially designed as a sponge, was transformed into an SHGT scaffold with improved brittle fracture resistance, thus broadening its potential applications in bone reconstruction. Moreover, the data showed that combining GT with RGD sequences and HA as a bioactive component significantly enhanced the viability of bone marrow stromal cells (BMSCs) cultured on the scaffold. This synergistic effect highlights the potential of the SHGT scaffold as a promising material for bone tissue engineering.

Healing persistent wounds is a current challenge for healthcare systems. Addressing this type of problem requires new and improved materials that activate regenerative processes without side effects. In this sense, in this study, C-phycocyanin (CPC), a bioactive pigment obtained from Arthrospira platensis, and nopal mucilage (MUC), a traditional Mexican element of ancestral medicine, were incorporated into gelatin (GEL)-based hydrogels and chemically crosslinked. These materials, referred to as HGEL-CPC-MUC, were prepared with varying concentrations of CPC-MUC (0-1 μg/μL of hydrogel), and their structural, physicochemical, rheological and in vitro biocompatibility properties were systematically evaluated. The main findings revealed that the incorporation of CPC-MUC into GEL-based hydrogels, significantly improves their physicochemical, mechanical and biological properties. These hydrogels exhibited a chemical crosslinking, achieving 93% crosslinking efficiency, high swelling behavior (∼1250%), rough porous surfaces, sustained degradation at physiological pH, and high thermal stability. Their rheological behavior showed an improvement in G' (226%) under thermal stress (40 °C), along with high damping capacity under constant load with the addition of CPC-MUC. Notably, the presence of CPC-MUC imparted a hemoprotective effect, with hemolysis percentages decreasing proportionally to the CPC-MUC content and none of the hydrogels interfered with coagulation pathways. Furthermore, all hydrogels demonstrated excellent in vitro biocompatibility with dermal fibroblasts, showing no cytotoxic effects. These features become important in the context of a moist and refractory wounds such as foot ulcers and extensive burns, were moisture control, exceptional hemocompatibility and support for dermal fibroblasts viability are required, as well as the porous structure for nutrients and waste exchange. HGEL-CPC-MUC hydrogels represent a highly promising biocompatible and multifunctional scaffold for advanced wound care and regenerative medicine applications.