Materials Science & Engineering C-Materials for Biological Applications最新文献

Inflammatory bowel disease (IBD) is a chronic, relapsing inflammatory disorder of the gastrointestinal tract that severely compromises quality of life. First-line therapy with 5-aminosalicylic acid (5-ASA) is limited by poor aqueous solubility, rapid upper gastrointestinal absorption and suboptimal colonic bioavailability. Although rectal administration targets the inflamed mucosa directly, conventional suppositories and enemas often reduce adherence due to discomfort and low acceptability. A thermo-sensitive in situ gelling hydrogel based on poloxamer 407 (P407) is designed to address these limitations. Exploiting its amphiphilic architecture and reversible sol-gel transition at physiological temperature, P407 enables efficient encapsulation of 5-ASA, enhances mucosal adhesion and sustains local drug release. The optimized formulation demonstrates an ideal gelation profile, high muco-adhesive strength, suitable mechanical resistance, excellent injectability and spreadability, preserving the antioxidant properties of 5-ASA. The drug release profile was prolonged, even under acidic pH conditions. In an inflamed intestinal co-culture model, P407-5-ASA hydrogels markedly reduce macrophage infiltration and TNF-α secretion. In a dextran sodium sulfate-induced murine colitis model, the formulation achieves higher colonic accumulation, prolonged residence time and significantly enhanced anti-inflammatory efficacy of 5-ASA. These results underscore the potential of P407-based hydrogels as a high-performance, patient-friendly platform for localized treatment of IBD.

Combined radiation-burn injury (CRBI) is a serious wound that is difficult to treat and typically results from radiation therapy, nuclear explosions, or nuclear accidents, where ionizing radiation and thermal burns usually occur simultaneously or sequentially. Excessive expression of reactive oxygen species (ROS) contributes to CRBI. Caffeic acid (CA) is a common natural antioxidant polyphenol whose clinical application is limited by its poor solubility and low stability. Here, we develop an in situ photocrosslinking caffeoyl chitosan/boronic acid-grafted gelatin hydrogel to treat CRBI. Caffeoyl chitosan (CCS) and boronic acid-grafted gelatin methacrylate (BGM) were synthesized. A CCS/BGM hydrogel was locally formed at the CRBI site due to the formation of dynamic caffeoyl/borate bonds and methacrylate photocrosslinking. The hydrogel showed appropriate swelling rates, mechanical properties, biosafety, and bioadhesion. ROS self-adaptive clearance of the hydrogel was realized by exposing CA phenolic groups after ROS breaking of caffeoyl/borate bonds to remove ROS. The hydrogel showed high mouse CRBI treatment efficacy by alleviating macrophages and proinflammatory cytokines (TNF-α and IL-6) and enhancing the expression of CD31 (a blood vessel formation biomarker). This ROS self-adaptive clearance hydrogel is a promising topical medicine for the treatment of high ROS-expressing CRBI and other complicated wounds.

Serious injury to the growth plate often leads to bony bridge formation, resulting in halted long bone growth, angular deformities, and limb length discrepancies. These problems persist unaddressed in the clinic. In this study, we engineered a four-layered growth plate organoid by integrating three-dimensional culture with layer-specific induction techniques. A gelatin/alginate hydrogel scaffold was utilized to recapitulate the architecture of the native growth plate. In the three cartilage zones, bone marrow derived mesenchymal stem cells (BMSCs) and chondrocytes were co-cultured at a 3:1 ratio and directed toward chondrogenesis with gradient concentrations of TGF-β3, resulting in cartilage tissue similar to the native growth plate. In the calcified zone, BMP-2 directed BMSCs toward mineralization. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were used to examine the microstructure of the gelatin/alginate hydrogel. Cell-based assays further confirmed the biocompatibility of the 3D culture system. A series of chondrogenic and osteogenic assays validated the successful formation of the organoid. In conclusion, by emulating the growth plate's distinct four-layered organization within a stratified hydrogel and applying targeted differentiation cues, we have established a highly biomimetic in vitro growth plate organoid. This model offers a novel platform for studying growth plate mechanisms and developing potential therapeutic strategies.

Designing multifunctional hydrogels that combine structural tunability with therapeutic responsiveness remains a key challenge in translational cancer nanomedicine. Here, we report the development of a GelMA-Fe-GQDs nanocomposite hydrogel engineered for 3D bioprintability and magnetically triggered hyperthermia. Physicochemical characterization confirmed controlled swelling (310 ± 28%) and enzymatic stability, with rheological testing revealing reinforced viscoelasticity and partial recovery (∼17.2 ± 6%) after high-strain disruption. The hydrogel exhibited ideal printability, producing stable filaments and droplets with consistent deposition fidelity. Under an alternating magnetic field (AMF) 313 kHz, ∼18 kA·m^-1, GelMA-Fe-GQDs hydrogels exhibited concentration-dependent heating, surpassing the therapeutic hyperthermia threshold (>42 °C) within 10 min at 1-2 mg·mL^-1, with a calculated specific absorption rate (SAR) of ∼175 W·g^-1 of Fe₃O₄. Thermal imaging confirmed uniform and localized heating within composite-containing regions. In vitro assays with triple negative breast cancer cells (TNBC) revealed high initial viability in both 2D and 3D cultures, with effective thermal ablation observed upon AMF exposure, validating the cytotoxic efficacy of magnetically induced heating. Collectively, these results establish GelMA-Fe-GQDs hydrogel as a printable, mechanically tunable, and magneto-responsive platform with potential for integration into 3D tumor models and localized cancer hyperthermia therapy.

Plant polyphenol-based hydrogels have gained widespread attention due to their unique and outstanding properties such as adhesion, antibacterial, self-healing and biocompatibility. The adhesion performance of these hydrogels can be systematically engineered to meet specific requirements, demonstrating significant potential in biomedical applications. This review initially explores the design strategies of hydrogels derived from different plant polyphenols. Subsequently, the multiple adhesive properties imparted by diverse design strategies, including dry adhesion, underwater adhesion, switchable adhesion, specific adhesion and asymmetrical adhesion are discussed. In addition, biomedical applications of plant polyphenol-based adhesive hydrogels, focusing on wound dressings, therapeutic drug delivery, cartilage tissue scaffolds and wearable electronics are summarized. In the end, remaining challenges and outline prospects for future research are discussed. It is hoped that this review can provide new innovation into the development of plant polyphenol-based adhesive hydrogels.

The rising demand for safe and effective alternatives for bone regeneration has spurred extensive research into biomaterials derived from marine collagen. This systematic review aimed to evaluate the feasibility of marine collagen-based compounds and derived constructs for bone regeneration in in vivo preclinical models while critically assessing the methodological quality of the included studies. The review was conducted following PRISMA guidelines, utilizing the PICO framework to delineate the scope and research focus. After applying predefined inclusion and exclusion criteria, a comprehensive search across multiple databases identified 15 eligible studies. Methodological quality was appraised using the ARRIVE 2.0 guidelines, and the risk of bias was weighed through the SYRCLE tool. The selected studies evaluated collagens derived from fish and marine sponges, which were processed into scaffolds, membranes, and hydrogels. These biomaterials exhibited notable biocompatibility, osteoconductivity, and efficacy in promoting new bone formation. Furthermore, synergistic combinations with hydroxyapatite, chitosan, and growth factors such as BMP-2 significantly enhanced their regenerative capacity. However, several critical shortcomings were observed in experimental designs, including inadequate randomization, absence of blinding, and insufficient reporting of animal handling protocols. These limitations raise concerns regarding reproducibility and the overall validity of the findings. In conclusion, marine collagen-based biomaterials hold significant potential for bone regeneration applications. Nevertheless, achieving greater standardization and methodological rigor in preclinical research is paramount to ensuring their successful clinical translation.

Poor implant-bone integration under osteoporotic conditions remains a critical clinical challenge. The osteoporotic microenvironment, characterized by excessive oxidative stress, immune homeostasis imbalance, and persistent chronic inflammation, significantly impedes bone regeneration. To address this issue, we fabricated a multifunctional bioactive coating on the surface of Ti implants, integrating antioxidant, immunomodulatory, and osteogenic properties. In this study, we synthesized an in-situ lanthanum oxide (La₂O₃) nanoparticle coating (denoted as AT/La₂O₃) on the surface of titanium implants using hydrothermal and high-temperature calcination techniques. Subsequently, regaloside A (RA), a bioactive compound with therapeutic potential, was loaded onto the coating via an impregnation method to obtain AT/La₂O₃/RA. The composite coating demonstrated sustained and stable release of both RA and La³⁺ ions. Meanwhile, AT/La₂O₃/RA exhibited good reactive oxygen species (ROS) scavenging capability. Furthermore, it significantly promoted macrophage polarization toward the M2 phenotype, upregulating anti-inflammatory cytokines (IL-4RA and IL-10) while downregulating pro-inflammatory mediators (TNF-α and MMP2), thereby mitigating chronic inflammation. In addition, the coating markedly enhanced the proliferation and osteogenic differentiation of MSCs. Furthermore, in vivo evaluations showed that AT/La₂O₃/RA could effectively attenuated oxidative stress and suppressed inflammatory responses, ultimately fostering robust osseointegration. These findings highlight the potential of AT/La₂O₃/RA as a promising surface modification strategy to improve implant performance in the clinics.

Brain tumors alter the viscoelastic equilibrium of surrounding tissue, but how these changes shape the mechanics of tumor-brain coupling remains unclear. This study introduces mechanical instability mapping, a voxelwise measure of imbalance between elastic storage and viscous dissipation derived from magnetic resonance elastography (MRE). Twenty-eight patients (15 meningiomas, 13 glioblastomas) were analyzed using standardized 3 T MRE and tumor segmentation. Quantitative descriptors of instability topology-including skeleton length and branch-point densities, and radial persistence (radial-AUC)-were compared across WHO I, WHO II, and glioblastoma groups. Glioblastomas showed diffuse, branched instability fields with significantly higher skeleton and branch-point densities and lower radial-AUC compared with WHO I meningiomas, which exhibited compact, radially coherent patterns. Group-average probability maps indicated a transition from coherent to fragmented instability with increasing malignancy. These findings demonstrate that peritumoral mechanical topology reflects the degree of viscoelastic coupling at the tumor-brain interface. Instability mapping thereby extends conventional stiffness-based MRE metrics, offering a quantitative framework for assessing interface integrity and heterogeneity that may aid in elasticity-guided treatment strategies and biomechanical phenotyping of brain tumors.

Developing multifunctional nanoplatforms for synergistic tumor therapy remains a significant challenge. Here, we report a metal-free bio-nanozyme (SL-BN) derived from the natural medicinal plant Solanum lyratum (SL) via a facile two-step solvothermal and carbonization method. The as-prepared SL-BN integrates triple-enzyme-like (peroxidase, oxidase, and catalase) activities with robust photothermal conversion capabilities across both near-infrared (NIR)-I and -II bio-windows. Within the tumor microenvironment, SL-BN initiates a cascaded catalytic reaction: its catalase-like activity decomposes endogenous H₂O₂ to self-supply O₂, thereby relieving hypoxia. This oxygen replenishment, in turn, fuels the oxidase-like activities to generate cytotoxic reactive oxygen species (ROS), creating a positive feedback loop for enzyme dynamic therapy (EDT). Crucially, upon NIR laser irradiation, the localized hyperthermia not only provides direct tumor ablation via photothermal therapy (PTT) but also significantly accelerates these enzymatic reaction rates. This photothermally self-enhanced synergistic strategy resulted in a tumor regression of 98.04% and 99.58% based on tumor volume and weight, respectively. This study presents a novel strategy for designing multifunctional bio-nanozymes from natural biomass and highlights the potential of integrating self-sustaining catalytic cycles with photothermal enhancement for highly effective tumor therapy.