title: Morphology-dependent antimicrobial activity of Cu/CuxO nanoparticles.
abstract: Cu/CuxO nanoparticles (NPs) with different morphologies have been synthesized with glucose as a reducing agent. The X-ray diffraction and Scanning electron microscopy imaging show that the Cu/CuxO NPs have fine crystalline peaks with homogeneous polyhedral, flower-like, and thumbtack-like morphologies. Their antimicrobial activities were evaluated on inactivation of Escherichia coli using a fluorescence-based live/dead staining method. Dissolution of copper ions from these NPs was determined. Results demonstrated a significant growth inhibition for these NPs with different morphologies, and the flower-like Cu/CuxO NPs were the most effective form, where more copper ions were dissolved into the culture media. Surface free energy calculations based on first-principle density functional theory show that different crystal facets of the copper NPs have diverse surface energy, indicating the highest reactivity of the flower-like NPs, which is consistent with the results from the dissolution study and antimicrobial activity test. Together, these results suggest that the difference between the surface free energy may be a cause for their morphology-dependent antimicrobial activity.
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Xiong
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China. zhtong@ustc.edu.cn.
authors.forename: Zhong-Hua
authors.initials: ZH
authors.lastname: Tong
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China.
authors.forename: Jie-Jie
authors.initials: JJ
authors.lastname: Chen
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China.
authors.forename: Ling-Li
authors.initials: LL
authors.lastname: Li
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China.
authors.forename: Han-Qing
authors.initials: HQ
authors.lastname: Yu
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology*; D003300:Copper / Q000737:chemistry / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D053768:Metal Nanoparticles / Q000032:analysis* / Q000737:chemistry
chemical_list: D000890:Anti-Infective Agents; D003300:Copper; C000520:cuprous oxide; C030973:cupric oxide
keywords: Antimicrobial activity; Copper nanoparticles; Morphology; Surface free energy