Edris Hoseinzadeh, Mohammad Reza Samargandi, Mohammad Yosef Alikhani, Ghodratollah Roshanaei, Ghorban Asgari,
Volume 5, Issue 3 (10-2012)
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Background and Objectives: Along with the rapid development of human life,
controlling harmful effects of
microorganisms would be unavoidable. The objective of this study was to
evaluate antibacterial efficacy of zinc oxide nanoparticles on different
microbial strains.
Material and Methods:
This experimental study was done using gram negative and gram positive bacteria
in nutrient media. Nanoparticle characterization was determined using X-ray
diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM).
Bacterial sensitivity to nanoparticles was tested using a disk diffusion test
and minimum inhibitory concentration (MIC). Time-kill studies and other tests
were carried out using 108 CFU/mL of bacteria at baseline. A point of zero
charge, pHzpc, of nanoparticle was investigated using the batch equilibration
method. Obtained data were managed by SPSS Ver.16 and were analyzed through the
Pearson, analysis of variance (ANOVA) and Student's independent t-tests. 0.05
was selected as significant level for all tests.
Results:
Characterization results from XRD, SEM, and TEM showed that particles are in
nano range and they do not contain any discernible crystalline impurity. The
average ZnO nanoparticles diameter was 20 nm. The pHZPC for ZnO was found to be
7.51. The P. aeruginosa strain exhibited larger diameter inhibition zone (DIZ)
to ZnO nanoparticle compared with other strains. Population of P.aeroginosa for
2 x MIC concentration was reduced to zero in the presence of nano ZnO within
150 min. The bacterial CFU had significant difference with contact time,
nanoparticles loading, and bacterial strain (P<0.001).
Conclusion: This study
demonstrated that antibacterial activity of ZnO can be a candidates for the
elimination of gram negative and gram positive bacteria, particularly in
nasocomial infection agent control.
