Journal of Materials Science: Materials in Medicine最新文献

Diabetic wound healing remains a significant clinical challenge, characterized by a protracted and uncertain prognosis. Extracellular vesicles (EVs), functioning as natural carriers released by living cells, play a pivotal role in intercellular communications by delivering diverse bioactive cargo. In recent years, plant-derived extracellular vesicles (PDEVs) have garnered increasing attention due to their inherent biocompatibility, safety, low immunogenicity, and abundant source availability. PDEVs are regarded as a highly promising cell-free therapeutic strategy for diabetic wound healing. This review systematically summarizes the research progress on PDEVs biogenesis, physiological functions and their underlying mechanisms, and isolation/characterization methodologies. Specifically, we explore the potential of PDEVs as drug delivery vehicles and discuss engineering strategies for their modification. Finally, we provide a critical analysis of the potential challenges associated with translating PDEVs into cell-free therapeutics for diabetic wounds and offer perspectives on future research directions.

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Mesoporous bioactive glasses (MBGs) have potential applications in bone tissue regeneration around tooth implant and local drug delivery. Small amounts of zinc added to their composition could additionally provide antibacterial and ossteoinductive and anti-inflammatory properties. In this study, zinc-containing mesoporous bioactive glasses (5ZnO–25CaO–70SiO₂) were synthesised using three modified surfactant-assisted sol-gel methods: dilute water (MZ1), Stöber (MZ2), and microemulsion-assisted (MZ3). X-ray diffraction (XRD) analysis confirmed that MZ1 and MZ3 were amorphous, while MZ2 exhibited a ZnO crystalline phase. The synthesised particles showed uniform morphology with sizes ranging from 10 to 500 nm. Brunauer–Emmett–Teller (BET) analysis revealed that MZ1 had the highest specific surface area (726 m²/g), approximately 4.1 times higher than MZ3 (176 m²/g). Haemolysis testing showed that MZ1 and MZ2 were non-haemolytic, whereas MZ3 caused lysis of erythrocytes. All samples were biocompatible with periodontal ligament fibroblasts, maintaining cell viability above 80% after three days of incubation. Antibacterial assays indicated that MZ2 exhibited over 60% inhibition of P. intermedia in a dose-dependent manner, but only ~20% inhibition of P. gingivalis. MZ2 demonstrated a bacteriostatic effect and was most effective in reducing anaerobic bacterial populations among all tested groups. These results highlight the potential of Zn-containing mesoporous bioactive glasses as multifunctional biomaterials for periodontal tissue engineering, suitable for such applications as scaffolds, bone cements, bone-filling granules, and antibacterial implant coatings. Furthermore, MZ2 material due to its antimicrobial properties, can potentially be a material of choice in periodontitis/peri-implantitis therapy applications.

In this study, we report the biogenic synthesis of ZnO-CuO nanocomposites (NCPs) utilizing Mentha longifolia leaf extract as both a reducing and capping candidate. The synthesis process was optimized utilizing the Plackett-Burman statistical design, achieving a maximum yield of 22.18 mg/mL under controlled conditions. The resulting ZnO-CuO NCPs exhibited a crystalline structure with an average particle size of 26.61 nm, as analyzed by XRD, TEM, and SEM approaches. FTIR spectroscopy demonstrated the presence of bioactive phytoconstituents, such as phenolic derivatives and alkaloids, which stabilized the nanocomposites. The ZnO-CuO NCPs demonstrated potent antimicrobial activity against multidrug-resistant pathogens, including Staphylococcus aureus, Escherichia coli, and Candida albicans, with a minimum inhibitory concentration (MIC) of 180.47 µg/mL. In anticancer evaluations, the ZnO-CuO NCPs exhibited selective cytotoxicity against A549 (lung), HepG2 (liver), and MDA (breast) cancer cell lines, with selectivity indices (SI) of 4.88, 25.19, and 46.32, respectively. Apoptosis induction was confirmed through nuclear staining and morphological analysis. Additionally, the ZnO-CuO NCPs showed promising antiviral activity against herpes simplex virus-1 (HSV-1) (IC₅₀ = 9.29 µg/mL, SI = 63.24) and Adenovirus-7 (IC₅₀ = 25.88 µg/mL, SI = 22.66), suggesting potential mechanisms involving viral replication inhibition. Molecular docking studies further supported the anticancer potential of the ZnO-CuO NCPs, revealing strong interactions with vascular endothelial growth factor (VEGF) and Bcl-2-associated protein x (Bax), key regulators of angiogenesis and apoptosis. These findings highlight the multifunctional therapeutic potential of plant-mediated ZnO-CuO NCPs, offering a sustainable and effective strategy for addressing antimicrobial resistance, cancer, and viral infections, with promising implications for future biomedical applications.

Chronic wound treatment presents a significant challenge, requiring bioactive scaffolds that facilitate effective wound repair and promote skin regeneration with normal functionality. In this study, gellan gum (GG) networks were formed via physical crosslinking with divalent cations, while silk sericin (SS), as the linear phase, molecularly penetrated the pore volume of the GG network, resulting in the formation of semi-interpenetrating polymeric networks (semi-IPNs). The GG/SS scaffolds were enriched with betel leaf extract-encapsulated β-cyclodextrin complexes (B-ICs) to preserve the bioactive substance, improve the controlled release, and provide antibacterial, antioxidant and anti-inflammatory properties. Characterization through XRD, FTIR, and thermal analyses confirmed successful encapsulation and enhanced thermal stability, while SEM imaging revealed well-formed microporous structures. Mechanical testing showed that B-ICs significantly improved the compressive modulus and strength of the scaffolds. Additionally, the controlled release behavior of the B-ICs-GG/SS scaffolds, confirmed by the Korsmeyer-Peppas model, suggested anomalous transport as the release mechanism, aligning with the faster in vitro degradation rate. The scaffolds exhibited high phenolic content, resulting in excellent free radical scavenging activity to minimize oxidative stress and support an optimal wound healing environment. In vivo skin irritation test in rabbits confirmed that B-ICs-GG/SS scaffolds were non-irritant, suggesting the dermal safety and biocompatibility of the materials, a critical requirement for clinical translation. As a result, the B-ICs-GG/SS scaffolds would be a promising candidate for wound healing and tissue engineering applications.

The need to improve biocompatibility and to ensure successful integration of biologically compatible metals or bio-metals with biological tissues has resulted in the development and creation of engineered surfaces as biomaterials for use as implants and bio-medical devices. Through laser surface texturing, precise control over surface micro-topography, and microstructure pattern can be achieved, that optimize and enhance cellular adhesion, growth and differentiation—key factors that prevent implant rejection and improve device functionality and performance. This study investigates nanosecond-pulsed, laser-engineered surface texturing on stainless steel, titanium, and cobalt-chromium alloys, particularly for use in biocompatible implants. Coupons of each material were textured using uniform laser parameters, resulting in engineered surfaces with distinct and defined peaks and valleys, creating micro-topographies influenced by the Gaussian profile of the laser, as analyzed via SEM (scanning electron microscopy) and optical profilometry. Surface analysis showed that engineered textures on stainless steel demonstrate high uniformity with surface roughness measured to be 0.897 μm (R_a), facilitating better cellular adhesion, an essential feature for implant integration. This was confirmed via water contact angle test that showed a moderately hydrophilic surface showing consistent behavior (mean Water Contact Angle (WCA)) close to 71.1°, variance 0.17). Energy dispersive X-ray spectroscopy (EDX) indicated minimal surface oxidation across all samples, consistent with processing under an inert gas environment. Additionally, a computational model was created to verify and validate the “experimental surface-textured” profiles of each of the materials within a 5% margin, confirming the accuracy and reproducibility of the laser-processing technique. The uniform micro-scale surface topography and preserved surface chemistry of SS316L show that it promotes cell-adhesion and enhanced potential for biomedical implant applications compared to Co-Cr and Ti-6Al-4V.

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Advances in bone tissue engineering and dental regenerative medicine have made strides in the development of several biomaterials. Optimizing the chemical and physical milieu of scaffold is required to induce osteogenesis for faster bone regeneration. In this study, polymer blend of Polyvinyl Alcohol (PVA) and Polyvinylpyrrolidone (PVP) doped with nHAP-ZnO Np was prepared by a solution casting technique. Structural and physiochemical characterization was performed. In vitro cytotoxicity analysis was performed through tetrazolium-based assay (MTT) assay and the differentiated cells were subjected to alkaline phosphatase assay (ALP) and alizarin red S (ARS) analysis respectively. Scanning Electron microscopic (SEM) analysis showed a rough and uniform matrix arrangement of the PVA-PVP blend. Crystallites properties and functional groups was confirmed by X ray diffractometer (XRD) analysis and Fourier transform infrared spectroscopy (FT-IR) respectively. The optimal water absorption capacity was observed in PVA-PVP-nHAP-ZnO Np scaffold (P3) and also degradation pattern was analysed for PVA-PVP (P1), PVA-PVP-nHAP (P2) and PVA-PVP-nHAP-ZnO Np (P3) scaffolds where P3 scaffold holds high stability compared to P1 and P2 scaffolds. In the thermal stability analysis, PVA-PVP (P1) and PVA-PVP-nHAP-ZnO Np (P3) scaffolds showed an overall stability up to 270 °C. Highly miscible blends of PVA-PVP and 1 wt% nHAP – ZnO Np was observed with semi-crystallinity in Differential Scanning Calorimetry (DSC) analysis. The mechanical property of the PVA-PVP-nHAP-ZnO Np (P3) scaffold has shown an increasing trend in tensile strength analysis. The cytotoxic study of scaffolds showed 84% of cell viability confirming high biocompatibility than compared to plain scaffold. the elevated level of ALP and calcium deposition was observed in loaded scaffold (P3). Thus, PVA-PVP-nHAP-ZnO Np (P3) scaffold supports and induces osteogenesis and can be used as biomaterial in bone regenerative medicine.

The objective of this study was to assess the friction reduction and antibacterial properties of orthodontic brackets and wires coated with ZnO-doped HAP nanoparticles. ZnO-doped HAP nanoparticles were characterized with SEM, FTIR, and XRD analysis. After characterization, ZnO-doped HAP nanoparticles were coated onto orthodontic brackets and wires employing the dip coating method. The samples were then divided into four groups, control group Z0 (uncoated wires and brackets, and HAP only) and experimental group Z5(5%ZnO+HAP), Z10 (10% ZnO+HAP), Z15 (15% ZnO+HAP). The prepared samples were then subjected to mechanical and antibacterial testing. Mechanical properties such as friction resistance and microhardness improved with the coating of ZnO-HAP nanoparticles. The lowest friction was observed for the Z15 group (7.81 ± 1.10 N) while the highest was observed for the control group Z0 (21.25 ± 0.92 N). Friction force decreased with coating and with increasing concentration of ZnO nanoparticles in the composites in the order of Z0 > Z5 > Z10 > Z15. Microhardness of the brackets and wires improved with the coating, with the highest microhardness values observed for groups Z10 and Z15 of 2253 ± 93.7 and 2239 ± 123.1, respectively. The hardness of the wires also improved with the coating with the lowest value observed for the uncoated Z0 (351 ± 45.17). Agar well diffusion test showed an inhibition zone of 11.3 ± 0.57 mm, 15.3 ± 0.57 mm, 14.6 ± 1.15 mm, and 15.1 ± 1.14 mm for Z0, Z5, Z10 and Z15, respectively. The result of this study showed that zinc oxide-doped hydroxyapatite nanoparticle coating improved the mechanical and antibacterial properties of orthodontic brackets and wires.

The development of small-diameter vascular grafts (SDVGs) remains a significant challenge and unsolved problem due to issues with compliance mismatch, thrombosis, and graft failure. This study explores electrospun blended scaffolds made from polyethylene terephthalate (PET) and polyurethane (PU), both Food and Drug Administration (FDA)-approved polymers, as potential candidates for small-diameter vascular applications. Nanofibrous scaffolds composed of blended PET and PU were fabricated using the electrospinning method. The morphological and chemical properties of the scaffolds were characterized by FE-SEM, porosity measurement, FTIR, and DSC. Comprehensive mechanical evaluations, including tensile strength, burst pressure, and compliance, were performed. Biocompatibility was assessed by examining cellular adhesion, proliferation, and viability on the scaffolds. For in vivo evaluation, the electrospun scaffolds were subcutaneously implanted in rats. The PET/PU blended scaffolds exhibited excellent physicochemical compatibility, with mechanical properties within the range of native small-diameter blood vessels (SDBVs). Burst pressure and compliance evaluations demonstrated the ability of the PET/PU blend to mitigate the compliance mismatch commonly observed in synthetic grafts. Additionally, the scaffolds supported strong human cell adhesion, proliferation, and high cell viability, indicating good biocompatibility. No signs of necrosis, calcification, severe fibrosis, inflammation, or foreign body granulomatous reaction were observed following subcutaneous implantation of the scaffolds. Electrospun PET/PU scaffolds offer promising mechanical and biocompatible properties for SDVGs applications. The ability to address compliance mismatch, combined with excellent cellular support, positions these scaffolds as a strong candidate for clinical use. However, further preclinical and clinical studies are necessary to validate their long-term safety, performance, and commercial viability.

High efficiency of anti-inflammatories for anti-inflammatory drugs has enormous room for improvement, aiming to reduce side effects. Herein, molecular-modified biomimetic mesoporous silica xerogel was applied to establish a superior carrier for delivering nimesulide (NMS). Small molecules of chiral threonine and chiral malic acid, as well as a polymer of hydroxypropyl methylcellulose K250 (HPMC), were used to respectively obtain LT-MSX, DT-MSX, LM-MSX, DM-MSX, BMSX, L-BMSX, M-BMSX, and H-BMSX. Morphology and porous structure of the obtained carriers were analyzed, and properties of NMS-loaded carriers were studied by focusing on drug crystal form and molecule interactions. In vitro carrier degradation and drug release, as well as in vivo anti-inflammatory effects of drug-loaded carriers, were evaluated. The results demonstrated that the addition of molecules significantly impacted the porous properties of carriers. In addition, all these carriers improved drug release by converting the drug crystal form to an amorphous state. The swelling inhibition rate of NMS-loaded LT-MSX and NMS-loaded DT-MSX was the best, owing to their fast drug release and silica degradation, which can be of great value for the application of anti-inflammatory drugs.

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