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Abstract Copper nanoparticles (CuNPs) embedded in polyvinylpyrrolidone (PVP) and polyethylene oxide (PEO) fiber‐matrices were prepared through centrifugal spinning of PVP/ethanol and PEO/aqueous solutions, respectively. The prime focus of the current study is to investigate the antibacterial activity of composite fibers againstEscherichia coli(E. coli) andBacillus cereus(B. cereus) bacteria. During the fiber formation, the centrifugal spinning parameters such as spinneret rotational speed, spinneret to collector distance, and relative humidity were carefully chosen to obtain long and continuous fibers. The structural and morphological analyses of both composite fibers were investigated using scanning electron microscopy, X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, and thermogravimetric analysis. In the antibacterial test, PVP/Cu and PEO/Cu composite fibrous membranes exhibited inhibition efficiency of 99.98% and 99.99% againstE. coliandB. cereusbacteria, respectively. Basically, CuNPs were well embedded in the fibrous membrane at the nanoscale level, which facilitated the inhibition of bacterial functions through the inactivation of the chemical structure of the cells. Such an effective antibacterial agent obtained from forcespun composite fibers could be promising candidates for biomedical applications.
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Copper-Based Antibiotic Strategies: Exploring Applications in the Hospital Setting and the Targeting of Cu Regulatory Pathways and Current Drug Design Trends
Classical antibacterial drugs were designed to target specific bacterial properties distinct from host human cells to maximize potency and selectivity. These designs were quite effective as they could be easily derivatized to bear next-generation drugs. However, the rapid mutation of bacteria and their associated acquired drug resistance have led to the rise of highly pathogenic superbug bacterial strains for which treatment with first line drugs is no match. More than ever, there is a dire need for antibacterial drug design that goes beyond conventional standards. Taking inspiration by the body’s innate immune response to employ its own supply of labile copper ions in a toxic attack against pathogenic bacteria, which have a very low Cu tolerance, this review article examines the feasibility of Cu-centric strategies for antibacterial preventative and therapeutic applications. Promising results are shown for the use of Cu-containing materials in the hospital setting to minimize patient bacterial infections. Studies directed at disrupting bacterial Cu regulatory pathways elucidate new drug targets that can enable toxic increase of Cu levels and perturb bacterial dependence on iron. Likewise, Cu intracellular chelation/prochelation strategies effectively induce bacterial Cu toxicity. Cu-based small molecules and nanoparticles demonstrate the importance of the Cu ions in their mechanism and display potential synergism with classical drugs.
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- Award ID(s):
- 1231306
- PAR ID:
- 10587153
- Publisher / Repository:
- Inorganics
- Date Published:
- Journal Name:
- Inorganics
- Volume:
- 11
- Issue:
- 6
- ISSN:
- 2304-6740
- Page Range / eLocation ID:
- 252
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/inorganics11060252
