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This study investigated the antibacterial activities of Se-Al/Zn layered double hydroxide (LDH) and its polycarbazole (PCz) hybrid against Gram-positive Bacillus subtilis and Gram-negative E. coli cells. Antibacterial performances were evaluated using zone of inhibition assays, viable cell counting, and measurement of metabolic activity based on intracellular ATP levels. The collective results showed that both materials exhibited significant antibacterial activity, with PCz–Se–Al/Zn LDH demonstrating enhanced antibacterial activity compared to Se–Al/Zn LDH. Fluorescent live/dead staining and scanning electron microscopy revealed that treatment with either material resulted in loss of metabolic activity and induction of a non-culturable state in bacterial cells, without observable membrane damage or pronounced morphological changes. Possible antibacterial mechanisms of action associated with LDH and PCz–LDH systems are briefly discussed.
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Influence of morphology and surface properties on the antibacterial action of GaOOH microparticles
The growing threat of antibiotic-resistant bacteria necessitates the development of alternative antimicrobial agents. Gallium oxyhydroxide (GaOOH) is a promising candidate, though its direct antibacterial efficacy is unexplored. This study provides the first direct evidence of GaOOH microparticles exhibiting cytotoxic effects against both Gram-positive Staphylococcus aureus (S.aureus) and Gram-negative Escherichia coli (E. coli). Orthorhombic GaOOH particles were synthesized hydrothermally, with their morphology influenced by the pH of the synthesis process, as confirmed by scanning electron microscopy and x-ray diffraction analysis. Antibacterial assays revealed that cytotoxicity against E. coli increases with a higher synthesis pH, a trend we demonstrate to be associated with the enhanced defect density in particles, as supported by photoluminescence spectra and FTIR analysis. The study underscores the significant influence of synthesis conditions on the morphology and crystallinity of the resulting GaOOH microparticles, highlighting the influence of surface characteristics on antibacterial agents.
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- Award ID(s):
- 2244258
- PAR ID:
- 10674267
- Publisher / Repository:
- AIP publishing
- Date Published:
- Journal Name:
- Biointerphases
- Volume:
- 20
- Issue:
- 1
- ISSN:
- 1934-8630
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1116/6.0004133
