Cu Nanoparticles Have Different Impacts in Escherichia coli and Lactobacillus brevis than Their Microsized and Ionic Analogues (original) (raw)
Related papers
ACS Nano, 2015
SUPPORTING INFORMATION AVAILABLE Additional details relate to: Supplemental Materials and Methods, growth inhibition effects of Cu species in E. coli and L. brevis (Figure S1), individual growth inhibition curve including error bars for each of the Cu species in E. coli and L. brevis (Figure S2), area under growth-inhibition curve for Cu species in E. coli and L. brevis (Figure S3), comparison of regression lines for area under the growth inhibition curve as a function of % Cu dissolved in media for E. coli and L. brevis (Figure S4) schematic of sucrose gradient centrifugation procedure (Figure S5), standard curve of OD 600 and total number of cells (Figure S6), Cu bioavailability determined using bacterial biosensor strain (Figure S7), and confocal images of cells treated with n-FITC-CuO (Figure S8). Tables of data include: sources of Cu particles (Table S1), correlation coefficients for area under the growth inhibition curve and amounts of dissolved copper in media, cell-associated Cu, and Cu bioavailable in each of the bacterial species (Table S2), correlation between results from growth inhibition assays and results from the suite of sub-lethal assays (Table S3), and References for Supporting Information. This material is available free of charge via the Internet at http://pubs.acs.org.
2010
Copper nanoparticles are used in wide variety of applications and in the current study we report the antimicrobial activity of these particles. Influence of pH, temperature, aeration rate, concentration of nanoparticles and concentration of bacteria on the toxicity of copper nanoparticles against Escherichia coli have been studied using a centroid mixture design of experiment. The linear and quadratic regression model shows that the toxicity of copper nanoparticles not only depends on the primary effect of the parameters tested (pH, temperature, aeration, concentration of E. coli and concentration of nanoparticles), but also on the interactive effect of these parameters.
Copper nanoparticles toxicity: Laboratory strains verses environmental bacterial isolates
Journal Of Environmental Science And Health, Part A, 2018
Nanoparticles have emerged as significant environmental contaminants and their impact has been studied using laboratory strains of bacteria. This study focuses on investigating the response of environmental isolate and laboratory strains of E. coli to 50 and 100 nm size of copper nanoparticles (CuNPs). The laboratory cultures included pathogenic and non-pathogenic strains. The environmental isolate and the non-pathogenic E. coli strain showed different inactivation patterns. After 2 h exposure to 50 nm CuNPs, the environmental isolate and the lab strain of E. coli lost 7.22 and 6.47 log; whereas the reduction of 6.16 and 6.68 log resulted after exposure to 100 nm CuNPs, respectively. The pathogenic E. coli O157:H7 exposed to 50 and 100 nm CuNPs for 2 h resulted in 5.24 and 6.54 log reduction, respectively. Although the environmental isolate and the laboratory strains of E. coli showed similar inactivation trends; they exhibited different toxicity elicitation mechanisms after exposure to the CuNPs. The pathogenic and non-pathogenic strains elicited significantly different levels of glutathione reductase (GR) activities, an enzyme critical for protection against radicals. Similarly, the environmental isolate and the lab strains of E. coli exhibited opposite trend in GR activities. These results clearly indicate divergence in the toxicity elicitation in the environmental isolate versus the laboratory strains from exposure to CuNPs, which highlights the need for an in-depth investigation of the impact of NPs on the biological processes and long-term effect of high load of NPs on the stability of aquatic and terrestrial ecologies.
Understanding the toxicity of aggregated zero valent copper nanoparticles against Escherichia coli
Journal of Hazardous Materials, 2010
Copper nanoparticles are used in wide variety of applications and in the current study we report the antimicrobial activity of these particles. Influence of pH, temperature, aeration rate, concentration of nanoparticles and concentration of bacteria on the toxicity of copper nanoparticles against Escherichia coli have been studied using a centroid mixture design of experiment. The linear and quadratic regression model shows that the toxicity of copper nanoparticles not only depends on the primary effect of the parameters tested (pH, temperature, aeration, concentration of E. coli and concentration of nanoparticles), but also on the interactive effect of these parameters.
2018
Cu nanoparticles were synthesized using low temperature aqueous reduction method at pH 3, 5, 7, 9 and 11. The nanoparticles were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), BET surface analysis and X-ray diffraction (XRD) techniques. Results demonstrated a strong dependence of synthesis pH on the size, shape, chemical composition and structure of Cu nanoparticles. While lower pH conditions produced Cu, high pH levels (more than 7) led to the formation of Cu2O/CuO nanoparticles. The results of in-vitro disk diffusion tests showed excellent antimicrobial activity Cu2O/CuO nanoparticles against a mixture of bacterial strains (Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa) indicating that the size as well as oxidation state of Cu contribute to the antibacterial efficacy.
BioMed Research International, 2015
Suspensions of Cu nanoparticles are promising for creating the new class of alternative antimicrobial products. In this study we examined copper nanoparticles of various sizes obtained by the method of wire electric explosion: nanopowder average size 50 nm (Cu 50) and 100 nm (Cu 100). The paper presents the complex study of the influence of physicochemical properties such as particle size and concentration of the freshly prepared and 24-hour suspensions of Cu nanoparticles in distilled water and physiological solution upon their toxicity to bacteriaE. coliM-17. Ionic solution of Cu2+and sodium dichloroisocyanurate was used for comparison study. It has been shown that decrease in the nanoparticle size leads to changes in the correlation between toxicity and concentration as toxicity peaks are observed at low concentrations (0.0001⋯0.01 mg/L). It has been observed that antibacterial properties of Cu 50 nanoparticle suspensions are ceased after 24-hour storage, while for Cu 100 suspens...
Mechanism of antibacterial activity of copper nanoparticles
Nanotechnology, 2014
In a previous communication, we reported a new method of synthesis of stable metallic copper nanoparticles (Cu-NPs), which had high potency for bacterial cell filamentation and cell killing. The present study deals with the mechanism of filament formation and antibacterial roles of Cu-NPs in E. coli cells. Our results demonstrate that NP-mediated dissipation of cell membrane potential was the probable reason for the formation of cell filaments. On the other hand, Cu-NPs were found to cause multiple toxic effects such as generation of reactive oxygen species, lipid peroxidation, protein oxidation and DNA degradation in E. coli cells. In vitro interaction between plasmid pUC19 DNA and Cu-NPs showed that the degradation of DNA was highly inhibited in the presence of the divalent metal ion chelator EDTA, which indicated a positive role of Cu 2+ ions in the degradation process. Moreover, the fast destabilization, i.e. the reduction in size, of NPs in the presence of EDTA led us to propose that the nascent Cu ions liberated from the NP surface were responsible for higher reactivity of the Cu-NPs than the equivalent amount of its precursor CuCl 2 ; the nascent ions were generated from the oxidation of metallic NPs when they were in the vicinity of agents, namely cells, biomolecules or medium components, to be reduced simultaneously.
Potential Antibacterial Activity of Green Synthesized Copper Nanoparticles and its Characterization
International Journal of Current Research and Review, 2021
Introduction and Objective: Copper oxide (CuO) nanoparticles are one of the most significant transition metal oxides in the burgeoning area of nanotechnology due to their intriguing features. Because of its simplicity, eco-friendliness, and potential as next-generation antibiotics, its synthesis using green chemistry principles is gaining traction. Cost-effectiveness, lower toxicity, and remarkable broad-spectrum antibacterial activity against a range of bacteria through the generation of reactive oxygen species (ROS) and release of copper ions. Materials and Methods: For CuO Nanoparticles synthesis Copper sulfate was used as starting material and its reduction was carried by Coriander Leaf Extract from Cu2+ to Cu0 The synthesized Cu nanoparticles were characterized by UV-Visible, FTIR and XRD methods. Transmission electron microscopy (TEM) demonstrated particle sizes in the range of 10-15 nm. CuO nanoparticles demonstrated antimicrobial activity against a range of Gram-positive and Gram-negative bacteria, including MRSA. Time kill determination assay was done. Results: According to TEM energy dispersive spectroscopy, the copper to oxygen element ratio is 54.18 per cent to 45.26 per cent. Most resistant human pathogenic strains, including Gram-positive and Gram-negative bacteria, showed significant inhibitory action (p0.0001). With a 31.66 mm zone of inhibition, the maximum effectiveness was recorded against Bacillus cereus. The addition of a sub-MIC concentration [broth dilution technique] of nano CuO reduced all populations to zero by 4 h. Conclusion: Studies of CuO nanoparticles suggest the release of ions may be required for optimum killing.
Growth inhibition of enterotoxigenic Escherichia coli by citrate capped copper nanoparticles
Nanoparticles have unique properties compared to their bulk counterparts due to their small size (less than 100 nm) and high surface-to-volume ratio. These allow a better interaction with cells and biological molecules. Because of this reason, nanotechnology has attracted a great deal of attention from the scientific community. Metal oxide nanomaterials like CuO, Ag and ZnO have been used industrially for several purposes. A common feature that nanoparticles exhibit is their antibacterial behavior against pathogenic bacteria. The present study aims on the synthesis and antimicrobial activity of CuO-NPs against Enterotoxigenic Escherichia coli (ETEC) and found that nanoparticles particularly copper oxide nanoparticles (CuO-NPs) can be a better alternative for diarrheagenic E. coli. Synthesis of CuO-NPs was achieved by Chemical route and capped by citrate to prevent agglomeration and were well characterized. We used these nanoparticles to evaluate their antibacterial activity against ETEC. The growth inhibition study of CuO-NPs was performed followed by time dependent study. Further, to elucidate its effect on DNA, the DNA damage study was also performed. The synthesized CuO-NPs showed growth inhibitory effect activity against ETEC. Further, the time dependent study showed the similar bactericidal activity of CuO-NPs after 16 hours. The CuO-NPs were effective enough to show DNA damage. In view of these, the CuO-NPs display, in fact, enhanced antibacterial properties and their synthesis procedures are quite cost effective. We envision that this study offers novel insights into antimicrobial actions of CuO-NPs which can be used as a novel class of topical antimicrobial agent for ETEC.
Investigations into the antibacterial behavior of copper nanoparticles against Escherichia coli
Annals of Microbiology, 2010
Zerovalent copper nanoparticles (Cu0) of 12 nm size were synthesized using an inert gas condensation method in which bulk copper metal was evaporated into an inert environment of argon with subsequent cooling for nucleation and growth of nanoparticles. Crystalline structure, morphology and estimation of size of nanoparticles were carried out by X-ray diffraction and transmission electron microscopy. The antibacterial activity of these nanoparticles against the Gram-negative bacterium Escherichia coli was assessed in liquid as well as solid growth media. It was observed from scanning electron microscopic analysis that the interaction of copper nanoparticles with E. coli resulted in the formation of cavities/pits in the bacterial cell wall. The antibacterial property of copper nanoparticles was attributed mainly to adhesion with bacteria because of their opposite electrical charges, resulting in a reduction reaction at the bacterial cell wall. Nanoparticles with a larger surface-to-volume ratio provide more efficient means for antibacterial activity.