Mahsa Jahangirrad - Water Purification Research Center, Tehran Medical Sciences, Islamic azad university, Tehran, Iran

Background and Aim : Antibacterial have been widely used in the textile industry, water disinfection, medicine and food packaging. Organic compounds used for disinfection have some drawbacks, including toxicity to the human body, therefore, the interest in inorganic disinfectants such as metal oxide nanoparticles (NPs) is increasing. The antibacterial mechanism of NPs depend on the applied dose and size and have been more effective for Gram-negative bacterium as compared to Gram-positive ones. In this study, synthesis of copper nanoparticles was approached by a single-precursor route via controlling the growth temperature.The current research examined the calculated inhibition of E-coli after adding various amounts of Cu-NPs to the culture medium.Methods : ۰.۰۱ mol Cu(acac)۲ was added to the three test flask, which contained ۵ mL oleylamine (OA) under Ar while, the temperature kept at ۲۰۰°C. This temperature kept at the selected value for ۵ h. The solutions, then, were cooled at room temperature and nanoparticles were obtained by centrifugation (۵ min) and washing. The as-prepared nanoparticles were dried in vacuum at ۶۰°C for ۲۴ h for further experiments. Growth curves of bacterial cell cultures were attained through repeated measures of the Optical Density (OD) at ۶۰۰ nm. A control medium, which contained no copper nanoparticles, was also used to examine the true differences between samples and control groups.Results : The growth curves of bacterial cells treated with Cu nanoparticles indicated that Cu could inhibit the growth and reproduction of bacterial cells. The bacterial growths of cells treated with ۵۰, ۱۰۰ and ۱۵۰ μg mL-۱ were inhibited. After ۲ h, almost all treated bacterial cells were dead.Conclusion : Cu-NPs showed anti bacterial activity against E. coli.

Copper nanoparticles, E- Coli, inhibition