The effect of silver nanoparticles on Escherichia coliand Staphylococcus aureus bacteria

The study of measuring the sensitivity of Escherichia coli and Staphylococcus aureus bacteriato silver nanoparticles was done using diffusion method in agar. The diameter of the non-growth halofor Escherichia coli bacteria was ۱۵.۵ mm and for Staphylococcus aureus bacteria was ۱۸.۵ mm. Inaddition, the broth microdilution method was used to determine the lowest concentration of thesubstance that inhibited the growth of the microorganism, known as the MIC concentration. Afterobserving the wells of the ۹۶-well plate to check the MIC concentration, ۱۰۰ microliters of the wells inwhich the bacteria did not grow were transferred to Mueller Hinton Agar culture medium (Merck-Germany) plates and incubated at ۳۷ degrees for ۲۴ to ۴۸ hours. After this period, the lowestconcentration that completely killed the bacteria was reported as MBC concentration. The resultsindicated that the MIC and MBC values for Staphylococcus bacteria are lower compared to Escherichiacoli.

Keywords:

Silver nanoparticles , antibiotic resistance , gram positive and gram negative bacteria , discdiffusion method , MIC and MBC