Journal of Biomaterials Applications最新文献

Tissue-engineered arteries using natural scaffolds could overcome the drawbacks of autografts or artificial conduits used in the repair of many congenital cardiac defects and coronary artery bypass grafts. In this study, we present a novel approach based on the use of decellularized xenogeneic matrix scaffolds preconditioned with human peripheral blood stem cells for future cardiovascular therapy. Cellular components of porcine carotid arteries (n = 40) were removed with physical, chemical and enzymatic means. The decellularized arteries were preconditioned by perfusion with human peripheral blood solution for 10 days. The decellularized and preconditioned grafts were characterized for their histological and functional integrity. To demonstrate proof-of-concept, we used a sub-acute (96 h) rabbit model where either only decellularized porcine arteries or preconditioned with autologous rabbit blood solution were implanted in the abdominal aorta of the animals. The rabbits were examined by Doppler ultrasound and histology. Histology and molecular analysis showed absence of cells and preservation of extracellular cell matrix (ECM) proteins in decellularized porcine arteries. Preconditioning of arteries with human blood showed a thin lining of intima with blood and cells. In the rabbit implant model, although blood flow was detected in all rabbits at 24 h, the animals implanted with only decellularized arteries showed lumen filled with thrombus. However, in preconditioned arteries, thrombosis was not seen at either 24 or 96 h. Taken together, these results suggest that these decellularization and preconditioning protocols using autologous blood may be adaptable for successful tissue-engineering of xeno-arteries for human application. However, further research to improve preconditioning efficiency and long-term animal studies are needed.

The development of nanoparticle-based wound dressings marks a significant advancement in the management of chronic and non-healing wounds. Silver-based dressings have been used in wound management due to their strong antimicrobial properties. However, their clinical effectiveness depends on formulation, concentration, and duration of use. Recently, copper oxide dressings (CODs) have emerged as a novel alternative, offering both antimicrobial and regenerative benefits. We reviewed clinical studies, meta-analyses, and cost-effectiveness analyses on silver nanoparticle (AgNP), ionic silver, nanocrystalline silver, and copper oxide dressings across various wound types, including diabetic foot ulcers, venous leg ulcers, pressure ulcers, surgical wounds, and burns. Emphasis was placed on dressing formulations, silver or copper concentrations, clinical efficacy, safety, and cost-effectiveness. Traditional silver formulations, such as silver sulfadiazine (1%) and silver nitrate (0.5%), demonstrate antimicrobial activity but are limited by cytotoxicity and lack of long-term healing benefits. Nanocrystalline silver and ionic silver hydrofiber dressings provide sustained release, proving most effective in infection-prone and early inflammatory phases. Enhanced formulations (Aquacel® Ag + Extra™) show promise in treating biofilm-related wounds but need more robust data. By contrast, CODs have demonstrated antimicrobial efficacy alongside stimulation of angiogenesis, fibroblast proliferation, and extracellular matrix remodeling. Early clinical evidence suggests that CODs may accelerate healing in refractory wounds and offer cost advantages over negative pressure therapy, though large-scale trials remain limited. Silver dressings, particularly nanocrystalline and ionic hydrofiber formulations, remain clinically useful for infection control and short-term wound management, while older silver salts are less favorable due to toxicity and limited efficacy. CODs represent a biologically attractive alternative with dual antimicrobial and regenerative properties. Nonetheless, the current body of evidence is insufficient to declare a paradigm shift in wound healing, and CODs should presently be regarded as promising adjuncts pending validation in high-quality randomized trials.

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.

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.

Decellularized liver scaffolds offer a promising foundation for liver tissue engineering and regenerative medicine. However, several challenges such as poor cell adhesion, inefficient reseeding, inadequate vascularization, and a high risk of blood clot formation continue to hinder their clinical application. While fibronectin (FN) has been widely used to enhance scaffold functionality, its potential for liver-specific applications remains largely unexplored. In this study, we developed a perfusion-assisted FN coating technique to improve the adhesion of endothelial cells (EA.hy926) and hepatocytes (HepG2), thereby enhancing the overall biocompatibility of liver scaffolds. FN was carefully introduced into decellularized rat liver scaffolds, allowing for targeted deposition across both the vascular and parenchymal compartments to optimize cellular attachment. Following portal vein reseeding and 7 days of bioreactor incubation, the FN-coated scaffolds showed significantly better endothelial cell adhesion within blood vessel structures and increased HepG2 cell coverage throughout the liver tissue. Immunohistochemistry (IHC) confirmed enhanced HepG2 proliferation, while TUNEL and RT-qPCR analyses indicated improved cell viability and scaffold functionality. Additionally, ex vivo blood perfusion tests demonstrated reduced thrombogenicity, likely due to improved endothelialization and lower platelet adhesion. These findings highlight FN functionalization as an effective bioengineering approach to overcoming key barriers in vascularization, biocompatibility, and cellular integration for liver scaffolds. By extending the known benefits of FN beyond its previously studied applications in kidney and heart scaffolds, this research introduces a promising strategy for advancing bioengineered liver grafts and potential transplantation models.

The collapsibility of bone cement may cause blood vessel embolism, blocking blood flow and causing serious complications such as pulmonary embolism or spinal cord injury, especially when implantation by injection. Therefore, it is of great significance to develop an artificial bone graft with excellent collapse resistance performance. Calcium sulfate and calcium phosphate complex bone cements can be formulated as injectable materials, making them particularly suitable for treating irregular bone defects. However, its clinical application is limited by poor collapsibility resistance and mechanical strength. This study aimed to develop an injectable bone repair material by integrating a biphasic calcium source, which was achieved by calcium sulfate (CS) and calcium phosphate (CP), and a synergistic network formed by sodium alginate (SA) and carboxymethyl chitosan (CMCS). The results showed that the addition of SA-CMCS as a solidifying liquid significantly improved the compressive strength, injectability, and collapsibility resistance of composite bone cement. At the concentration of 1% SA and 15% CMCS, the peak compressive strength reached 11.53 ± 1.3 MPa. All the composite bone cements did not collapse at 5 h in the static environment, and the collapse times of samples SA1-CMCS15 and SA1-CMCS20 in the dynamic environment were 95.3 ± 5.1 min and 96.7 ± 4.9 min, respectively. At CMCS concentrations of 10-20%, the injectability of composite bone cement was higher than 90% and degradation ratio was less than 15%. ALP activity and alizarin red staining confirmed that the composite bone cement showed excellent cytocompatibility and promoted cell proliferation and osteogenic differentiation. This study successfully developed a bone repair material with enhanced mechanical properties, collapsibility resistance, injectability, and biocompatibility, which may make it a promising candidate for bone regeneration applications in clinical.

Hydrogels are advantageous for wound healing as they provide mechanical support and maintain a moist environment, essential for tissue repair. Although conventional alginate-based hydrogels are commonly used in wound care, they often lack essential properties like antibacterial and antioxidant functionality. To address this limitation, this research focused on synthesizing composite hydrogels combining alginate with lignin and loading them with Vancomycin. The incorporation of lignin and Vancomycin imparted antibacterial and antioxidant properties to the hydrogels, enhancing their therapeutic potential. The hydrogels are dual crosslinked (physically and chemically), where lignin counteracts high levels of reactive oxygen species and reduces excessive inflammation at the wound site. Furthermore, the hydrogels had pores ranging from 100 to 135 μm, which is beneficial to gas and nutrient exchange and wound fluid absorption. Results showed that lignin improved the hydrogels' stability in physiological conditions by 50%. Additionally, the incorporation of lignin led to a 30% increase in antioxidant activity and a 50% boost in antibacterial activity. Vancomycin release from the hydrogels was measured, which showed alginate-only hydrogels releasing 50% and lignin-reinforced hydrogels releasing 35% over the first 24 hours. The MTT test confirmed approximately 90% cell viability across all samples, suggesting that the designed hydrogels are promising candidates for wound dressing applications.