Potential applications of advance functional polymeric nanofibers in biomedical and environmental engineering （優れた機能性を備えた高分子ナノファイバーの医療用・環境工学への応用の可能性に関する研究）

信州大学(Shinshu university)博士（工学）この博士論文は、次の学術雑誌論文を一部に使用しています。 / Current Research in Biotechnology 1:1-10 (2019); doi:10.1016/j.crbiot.2019.07.001. © 2019 The Author(s). Published by Elsevier B.V. / MATERIALS TODAY COMMUNICATIONS 24:101161 (2020); doi:10.1016/j.mtcomm.2020.101161. © 2020 Published by Elsevier. / POLYMERS 12(11):2524 (2020); doi:10.3390/polym12112524. © 2020 by the authors. / INTERNATIONAL JOURNAL OF NANOMEDICINE 14:2693-2703 (2019); doi:10.2147/IJN.S197665. © 2019 Ullah et al. This work is published and licensed by Dove Medical Press Limited.ThesisHASHMI, MOTAHIRA. Potential applications of advance functional polymeric nanofibers in biomedical and environmental engineering （優れた機能性を備えた高分子ナノファイバーの医療用・環境工学への応用の可能性に関する研究）. 信州大学, 2021, 博士論文. 博士（工学）, 甲第764号, 令和03年03月20日授与.doctoral thesi

Electrospun PVA/CuONPs/Bitter Gourd Nanofibers with Improved Cytocompatibility and Antibacterial Properties: Application as Antibacterial Wound Dressing

Antibacterial and cyto-compatible tricomponent composite electrospun nanofibers comprised of polyvinyl alcohol (PVA), copper II oxide nanoparticles (CuONPs), and Momordica charantia (bitter gourd, MC) extract were examined for their potential application as an effective wound dressing. Metallic nanoparticles have a wide range of applications in biomedical engineering because of their excellent antibacterial properties; however, metallic NPs have some toxic effects as well. The green synthesis of nanoparticles is undergoing development with the goal of avoiding toxicity. The aim of adding Momordica charantia extract was to reduce the toxic effects of copper oxide nanoparticles as well as to impart antioxidant properties to electrospun nanofibers. Weight ratios of PVA and MC extract were kept constant while the concentration of copper oxide was optimized to obtain good antibacterial properties with reduced toxicity. Samples were characterized for their morphological properties, chemical interactions, crystalline structures, elemental analyses, antibacterial activity, cell adhesion, and toxicity. All samples were found to have uniform morphology without any bead formation, while an increase in diameters was observed as the CuO concentration was increased in nanofibers. All samples exhibited antibacterial properties; however, the sample with CuO concentration of 0.6% exhibited better antibacterial activity. It was also observed that nanofibrous mats exhibited excellent cytocompatibility with fibroblast (NIH3T3) cells. The mechanical properties of nanofibers were slightly improved due to the addition of nanoparticles. By considering the excellent results of nanofibrous mats, they can therefore be recommended for wound dressing applications

Electrospun Composite Nanofibers for Functional Applications

Summary of the Special Issue: [...

Optimized Loading of Carboxymethyl Cellulose (CMC) in Tri-component Electrospun Nanofibers Having Uniform Morphology

Cellulose is one of the most hydrophilic polymers with sufficient water holding capacity but it is unstable in aqueous conditions and it swells. Cellulose itself is not suitable for electrospun nanofibers’ formation due to high swelling, viscosity, and lower conductivity. Carboxymethyl cellulose (CMC) is also super hydrophilic polymer, however it has the same trend for nanofibers formation as that of cellulose. Due to the above-stated reasons, applications of CMC are quite limited in nanotechnology. In recent research, loading of CMC was optimized for electrospun tri-component polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and carboxymethyl cellulose (CMC) nanofibers aim at widening its area of applications. PVA is a water-soluble polymer with a wide range of applications in water filtration, biomedical, and environmental engineering, and with the advantage of easy process ability. However, it was observed that only PVA was not sufficient to produce PVA/CMC nanofibers via electrospinning. To increase spinnability of PVA/CMC nanofibers, PVP was selected as the best available option because of its higher conductivity and water solubility. Weight ratios of CMC and PVP were optimized to produce uniform nanofibers with continuous production as well. It was observed that at a weight ratio of PVP 12 and CMC 3 was at the highest possible loading to produce smooth nanofibers

Electrospun PVA/CuONPs/Bitter Gourd Nanofibers with Improved Cytocompatibility and Antibacterial Properties: Application as Antibacterial Wound Dressing

Antibacterial and cyto-compatible tricomponent composite electrospun nanofibers comprised of polyvinyl alcohol (PVA), copper II oxide nanoparticles (CuONPs), and Momordica charantia (bitter gourd, MC) extract were examined for their potential application as an effective wound dressing. Metallic nanoparticles have a wide range of applications in biomedical engineering because of their excellent antibacterial properties; however, metallic NPs have some toxic effects as well. The green synthesis of nanoparticles is undergoing development with the goal of avoiding toxicity. The aim of adding Momordica charantia extract was to reduce the toxic effects of copper oxide nanoparticles as well as to impart antioxidant properties to electrospun nanofibers. Weight ratios of PVA and MC extract were kept constant while the concentration of copper oxide was optimized to obtain good antibacterial properties with reduced toxicity. Samples were characterized for their morphological properties, chemical interactions, crystalline structures, elemental analyses, antibacterial activity, cell adhesion, and toxicity. All samples were found to have uniform morphology without any bead formation, while an increase in diameters was observed as the CuO concentration was increased in nanofibers. All samples exhibited antibacterial properties; however, the sample with CuO concentration of 0.6% exhibited better antibacterial activity. It was also observed that nanofibrous mats exhibited excellent cytocompatibility with fibroblast (NIH3T3) cells. The mechanical properties of nanofibers were slightly improved due to the addition of nanoparticles. By considering the excellent results of nanofibrous mats, they can therefore be recommended for wound dressing applications

Evaluating Antibacterial Efficacy and Biocompatibility of PAN Nanofibers Loaded with Diclofenac Sodium Salt

Side effects of the drugs’ oral administration led us to examine the possibility of using diclofenac sodium (DLF) in a polymeric drug delivery system based on electrospun polyacrylonitrile (PAN) nanofibers, which can be produced cost-effectively and with good applicability for transdermal treatments. The inclusion of DLF in PAN nanofibers increased the nanofiber diameter from ~200 nm to ~500 nm. This increase can be attributed to the increase in the spinning solution viscosity. FTIR spectra confirm the entrapment of the DLF into the PAN nanofibers. X-ray diffraction pattern showed that the inclusion of the DLF in the PAN nanofibers had caused the misalignment in the polymeric chains of the PAN, thus resulting in a decrease of the peak intensity at 2θ = 17o. The DLF loaded PAN nanofibers were efficient against the gram-positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli), with maximum inhibition zone of 16 ± 0.46 mm for E. coli and 15.5 ± 0.28 mm for S. aureus. Good cell viability ~95% for L929 cells in more extended incubation periods was reported. A gradual release of DLF from the PAN nanofiber was observed and can be attributed to the stability of Pan in PBS medium. Cell adhesion micrographs show that cell-cell interaction is stronger than the cell-material interaction. This type of weak cell interaction with the wound dressing is particularly advantageous, as this will not disturb the wound surface during the nursing of the wound

Fabrication of Novel Hemp Charcoal Nanofiber Membrane for Effectual Adsorption of Heavy Metal Ions from Wastewater

Water pollution is increasing with rapidly growing industries and world population, which is very harmful for marine life and humans as well. This research has been conducted to introduce novel material with advanced techniques for the effective removal of heavy metals from wastewater. Successful nanofiber membranes have been developed with hemp charcoal (HC) and polyacrylonitrile (PAN), which can remove heavy metals from water efficiently in less time. The nanofiber membranes showed good adsorption capacity for heavy metal ions along with good thermal and mechanical stability. Electrospun nanofibers of HC and PAN were assessed for adsorption capacity by soaking them in metallic suspensions of known concentration for a specific period of time. Nickle, cobalt, and copper metals were selected to assess the adsorption capacity of nanofibrous webs. It was observed that HC played a vital role in removing metal ions from wastewater with an excellent efficiency. The adsorption capacity for nickel, cobalt, and copper was 54 mg/g, 87 mg/g, and 96 mg/g, respectively