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  1. Abstract

    Zinc oxide nanoparticles (ZnO NPs) are versatile and promising, with diverse applications in environmental remediation, nanomedicine, cancer treatment, and drug delivery. In this study, ZnO NPs were synthesized utilizing extracts derived fromAcacia catechu, Artemisia vulgaris, andCynodon dactylon. The synthesized ZnO NPs showed an Ultraviolet–visible spectrum at 370 nm, and X-ray diffraction analysis indicated the hexagonal wurtzite framework with the average crystallite size of 15.07 nm, 16.98 nm, and 18.97 nm for nanoparticles synthesized utilizingA. catechu, A. vulgaris,andC. dactylonrespectively. Scanning electron microscopy (SEM) demonstrated spherical surface morphology with average diameters of 18.5 nm, 17.82 nm, and 17.83 nm for ZnO NPs prepared fromA. catechu, A. vulgaris, andC. dactylon,respectively. Furthermore, ZnO NPs tested againstStaphylococcus aureus, Kocuria rhizophila, Klebsiella pneumonia,andShigella sonneidemonstrated a zone of inhibition of 8 to 14 mm. The cell viability and cytotoxicity effects of ZnO NPs were studied on NIH-3T3 mouse fibroblast cells treated with different concentrations (5 μg/mL, 10 μg/mL, and 50 μg/mL). The results showed biocompatibility of all samples, except with higher doses causing cell death. In conclusion, the ZnO NPs synthesized through plant-mediated technique showed promise for potential utilization in various biomedical applications in the future.

     
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    Free, publicly-accessible full text available March 1, 2025
  2. Electrospun fibrous scaffolds made from polymers such as polycaprolactone (PCL) have been used in drug delivery and tissue engineering for their viscoelasticity, biocompatibility, biodegradability, and tunability. Hydrophobicity and the prolonged degradation of PCL causes inhibition of the natural tissue-remodeling processes. Poliglecaprone (PGC), which consists of PCL and Poly (glycolic acid) (PGA), has better mechanical properties and a shorter degradation time compared to PCL. A blend between PCL and PGC called PPG can give enhanced shared properties for biomedical applications. In this study, we fabricated a blend of PCL and PGC nanofibrous scaffold (PPG) at different ratios of PGC utilizing electrospinning. We studied the physicochemical and biological properties, such as morphology, crystallinity, surface wettability, degradation, surface functionalization, and cellular compatibility. All PPG scaffolds exhibited good uniformity in fiber morphology and improved mechanical properties. The surface wettability and degradation studies confirmed that increasing PGC in the PPG composites increased hydrophilicity and scaffold degradation respectively. Cell viability and cytotoxicity results showed that the scaffold with PGC was more viable and less toxic than the PCL-only scaffolds. PPG fibers were successfully coated with polydopamine (PDA) and collagen to improve degradation, biocompatibility, and bioactivity. The nanofibrous scaffolds synthesized in this study can be utilized for tissue engineering applications such as for regeneration of human articular cartilage regeneration and soft bones.

     
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  3. Free, publicly-accessible full text available October 25, 2024
  4. A laboratory-synthesized triblock copolymer poly(ethylene oxide-b-acrylic acid-b-styrene) (PEG-PAA-PS) was used as a template to synthesize hollow BaCO3 nanoparticles (BC-NPs). The triblock copolymer was synthesized using reversible addition–fragmentation chain transfer radical polymerization. The triblock copolymer has a molecular weight of 1.88 × 104 g/mol. Transmission electron microscopy measurements confirm the formation of spherical micelles with a PEG corona, PAA shell, and PS core in an aqueous solution. Furthermore, the dynamic light scattering experiment revealed the electrostatic interaction of Ba2+ ions with an anionic poly(acrylic acid) block of the micelles. The controlled precipitation of BaCO3 around spherical polymeric micelles followed by calcination allows for the synthesis of hollow BC-NPs with cavity diameters of 15 nm and a shell thickness of 5 nm. The encapsulation and release of methotrexate from hollow BC-NPs at pH 7.4 was studied. The cell viability experiments indicate the possibility of BC-NPs maintaining biocompatibility for a prolonged time. 
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  5. Zinc oxide nanoparticles (ZnO-NPs) have piqued the curiosity of researchers all over the world due to their extensive biological activity. They are less toxic and biodegradable with the capacity to greatly boost pharmacophore bioactivity. ZnO-NPs are the most extensively used metal oxide nanoparticles in electronic and optoelectronics because of their distinctive optical and chemical properties which can be readily modified by altering the morphology and the wide bandgap. The biosynthesis of nanoparticles using extracts of therapeutic plants, fungi, bacteria, algae, etc., improves their stability and biocompatibility in many biological settings, and its biofabrication alters its physiochemical behavior, contributing to biological potency. As such, ZnO-NPs can be used as an effective nanocarrier for conventional drugs due to their cost-effectiveness and benefits of being biodegradable and biocompatible. This article covers a comprehensive review of different synthesis approaches of ZnO-NPs including physical, chemical, biochemical, and green synthesis techniques, and also emphasizes their biopotency through antibacterial, antifungal, anticancer, anti-inflammatory, antidiabetic, antioxidant, antiviral, wound healing, and cardioprotective activity. Green synthesis from plants, bacteria, and fungus is given special attention, with a particular emphasis on extraction techniques, precursors used for the synthesis and reaction conditions, characterization techniques, and surface morphology of the particles. 
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