Sima sedrizadeh Bami - Department of Microbiology, Kerman Branch, Islamic Azad University, Kerman, Iran.
Ashraf Kariminik - Department of Microbiology, Kerman Branch, Islamic Azad University, Kerman, Iran.

Introduction and Objectives: Serious infections are associated with methicillin-resistant Staphylococcus aureus (MRSA) bacteria and this can lead to many deaths in the world. This mortality rate is due to an increase in antibiotic resistance among bacteria. Nano-silver particles have found many applications as alternative antimicrobials in recent years. The aim of the present study was synthesis of silver nanoparticles to evaluate the antibacterial effect against Methicillin-Resistant Staphylococcus aureus (MRSA) isolates from clinical samples. Materials and Methods: Silver nanoparticles was synthesized by micellelation assisted ultrasonic method. The as-prepared silver nanoparticles were characterized with X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM). The XRD studies showed that pure Ag nanoparticles have been produced after calcination.The antibacterial effect of silver nanoparticles was performed using Agar well diffusion assay and minimum inhibitory concentration (MIC) was determined. Results: Based on obtained findings, synthesized silver nanoparticles showed favorable effects on the bacterial isolates. The mean MIC and MBC value were determined as 0.015 mg/ml and 0.07 mg/ml, respectively. All MRSA isolates were susceptible to more than MIC of nanosilver in contrast showed high resistance to multiple classes of antibiotics. Conclusion: silver Nanoparticles have high inhibitory activity against MRSA, thus can be proposed as an alternative or adjuvant with antibiotics for MRSA treatment. Further investigations are required to assess the safety and efficacy of nano- silver particles in the body.

Silver nanoparticles, Methicillin-Resistant Staphylococcus aureus, Antibacterial effects.