Hydrothermal synthesis of copper based nanoparticles: antimicrobial screening and interaction with DNA.
Copper based nanoparticles (Cu-based NPs) of different compositions and sizes have been hydrothermally synthesized by varying the reaction time in the presence of the biocompatible surfactants polyoxyethylene (20) sorbitan laurate (Tween 20) and polyethylene glycol 8000 (PEG 8000). Effective control of the above synthetic parameters gave rise to Cu, Cu2O and Cu/Cu2O NPs of 10-44 nm. The antibacterial activity of the NPs was screened against Gram-positive (Bacillus subtilis, Bacillus cereus, Staphylococcus aureus) and Gram-negative (Xanthomonas campestris, Escherichia coli) bacteria. The Cu-based NPs induce pDNA degradation in a dose-dependent manner as well as extensive ds CT-DNA degradation. Cu2O NPs of 16 nm and 12 nm exhibit the lowest IC50 values (2.13 μg/mL and 3.7 μg/mL) against B. cereus and B. subtilis, respectively. The agarose gel electrophoresis of ds CT-DNA treated with Cu2O NPs demonstrated degradation at high concentration. In lower concentrations, viscosity measurements indicated groove binding. In regard to the enhanced antibacterial effect and specificity of Cu2O NPs against the Gram-positive strains, the activity pathway was further explored and ROS production and lipid peroxidation verified. The released copper ions 5.15 mg/L in distilled water and 16.32 mg/L in nutrient medium, found below the critical value to inhibit bacterial growth and thus nanosized composition effect is predominant.
Lab. of Inorganic Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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Giannousi
Lab. of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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Lafazanis
Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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Arvanitidis
Lab. of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece. Electronic address: natasa@chem.auth.gr.
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Pantazaki
Lab. of Inorganic Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece. Electronic address: samkat@chem.auth.gr.
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Dendrinou-Samara
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004926:Escherichia coli / Q000187:drug effects; D015227:Lipid Peroxidation / Q000187:drug effects; D053768:Metal Nanoparticles / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D046529:Microscopy, Electron, Transmission; D013211:Staphylococcus aureus / Q000187:drug effects
D000900:Anti-Bacterial Agents; D003300:Copper; D004247:DNA
Antibacterial activity; Copper based nanoparticles; DNA degradation; Ionic release; Lipid peroxidation; Reactive oxygen species