Journal of Materials Science: Materials in Medicine最新文献

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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The study aims to develop a composite coating for magnesium aluminum alloy (MA) to improve its corrosion/infection resistance. MA was coated with carboxymethyl chitosan (CMCS) and nano-hydroxyapatite (HA) through electrophoretic deposition, followed by the deposition of vancomycin-loaded polymer nanoparticles to obtain the ternary composite coating alloy (VAN@PLGA/HA/CMCS-MA). In simulated body fluid (SBF), the average corrosion rate of the coating alloy was 0.27 ± 0.03 mg/cm⁻¹/day⁻¹, while maintaining a pH level of approximately 7.2, indicating that the composite coatings effectively mitigated erosion in SBF and ensured a stable physiological pH. In vitro antibacterial experiments showed that VAN@PLGA/HA/CMCS-MA exhibited enhanced antibacterial activity against staphylococcus aureus and enterococcus faecalis compared to single MA owing to sustained antibiotic release. Furthermore, the composite coating promoted alkaline phosphatase activity and induced extracellular Ca²⁺ mineralization, suggesting good bone-promoting ability of the alloy. Finally, the biocompatibility studies confirmed that the composite coating could reduce mild toxicity of the alloy following corrosion, resulting in enhanced cell viability and reduced hemolysis rate. Overall, the ternary composite alloy coating delayed MA degradation and provided long-term effective corrosion/infection resistance.

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Mechanical compatibility is a major challenge in designing orbital bone scaffolds, which involving material selection, structural design and fabrication processes. In this study, a novel impact model database containing essential components involved in tissue engineering repair of orbital fracture was established for finite element analysis (FEA). The mechanical compatibility between various pattern-designed scaffold and the orbital bone defect site was tested to raise the optimized square pattern filled scaffold for the subsequent study. Based on the optimized structure, 3D printed bone scaffolds with different β-TCP contents were fabricated. It was confirmed that the composite scaffold containing 30% β-TCP and 70% polycaprolactone (PCL@30TCP) demonstrated significantly enhanced hydrophilicity, mechanical strength, water absorption, and accelerated degradation relative to other groups (p < 0.05). In vitro evaluations confirmed the significant advantages in cytocompatibility and osteogenic activity of PCL@30TCP scaffold (p < 0.05). Furthermore, rabbit orbital defect repair experiments demonstrated that the 3D-printed PCL@30TCP scaffold markedly promoted osteogenesis at the defect site through three synergistic mechanisms: enhancing neo-bone formation and maturation, guiding tissue growth into the interior structure of scaffold, and obviously upregulating bone morphogenetic protein 2 (BMP-2) and osteocalcin (OCN) expression (p < 0.05). Importantly, comprehensive biosafety assessments validated the clinical applicability of the PCL@30TCP scaffold. These findings indicate that the square-patterned PCL@30TCP 3D-printed scaffold exhibits exceptional osteogenic performance both in vitro and in vivo, demonstrating clinical potential for orbital bone defect repair.

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The use of targeted drug delivery systems to accumulate medications in cancer cells, along with the simultaneous application of multiple drugs, can facilitate the administration of optimal doses, leading to more efficient treatment as well as reduced side effects. We fabricated zirconium-based UiO-66-NH₂ metal-organic framework (MOF) nanoparticles (NPs) with folic acid (FA) conjugated onto their surface for targeted delivery of doxorubicin (DOX), and smart drug release within tumor cells. Following the physicochemical characterization of the prepared NPs, the drug release profile was investigated in simulated media with pH 5.4 and 7.4. Subsequently, the internalization and anticancer effects of the NPs were evaluated in HT-29 and HEK-293 cells to assess their selectivity. Simultaneous treatment of HT-29 cells with FA-decorated NPs and hydroxychloroquine (HCQ), an autophagy inhibitor, was performed to sensitize cancer cells. The synergistic effects of combined treatment were assessed through MTT assay and autophagy flux detection. UiO-66-NH₂-FA@DOX NPs with a surface area of 323 m²/g and a high loading capacity of 36.25% showed a pH-dependent release with a substantial increase in acidic condition. Higher uptake of targeted NPs in HT-29 cells led to higher cytotoxicity and apoptosis. The combination of HCQ and targeted NPs increased cytotoxic effects against HT-29 cells compared to treatment with targeted NPs alone. Acridine orange staining revealed different patterns of autophagy flux in the co-administered drug groups. This study suggests that our DOX-loaded targeted nanocarrier enhances the therapeutic efficacy through localized drug delivery and reduced potential side effects compared to conventional DOX treatment. Its combination with HCQ may offer a promising strategy for safer and more effective colorectal cancer therapy by enabling dose reduction of both agents. However, further in vivo studies are necessary to validate these findings.

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This study aimed to develop a versatile aptamer-conjugated, photothermal responsive camptothecin (CPT)-loaded chitosan-bimetallic (Pd/Au) nanoparticles (Ap-CH-CPT-Pd/Au NPs) to enhance cytotoxicity in lung cancerous NCI-H446 and H1299 cells. The CH-CPT-Pd/Au NPs exhibited polydispersity with a diameter of 33.87 ± 2.23 nm. FTIR investigation revealed the presence of chitosan and camptothecin in chitosan-camptothecin-palladium/gold nanoparticles. The 2θ of CH-CPT-Pd/Au corresponded to chitosan and palladium/gold. The Ap-CH-CPT-Pd/Au NPs (180 μg/mL) subjected to near-infrared (NIR) treatment elevated the temperature to over 50 °C. The optimum CPT concentration was 0.075% in CH-CPT-Pd/Au, demonstrating a hydrodynamic diameter of 113.12 ± 16.78 nm, a drug loading efficiency (DLE) of 10.89 ± 0.53%, and a drug encapsulation efficiency (DEE) of 63.97 ± 4.21%. A CPT release rate of 7.23 ± 3.25% was recorded at pH = 5.4 after 74 h. In addition, NIR+Ap-CH-CPT-Pd/Au NPs exhibited negligible toxicity to red blood cells (RBCs). However, enhanced cytotoxicity in NCI-H446 and H1299 lung carcinoma cells is achieved through the induction of oxidative stress-mediated apoptosis.