AAPS PharmSciTech

, Volume 19, Issue 3, pp 1133–1140 | Cite as

Promising Antibacterial Effects of Silver Nanoparticle-Loaded Tea Tree Oil Nanoemulsion: a Synergistic Combination Against Resistance Threat

  • Roqya Najafi-taher
  • Behnaz Ghaemi
  • Sharmin Kharazi
  • Samira Rasoulikoohi
  • Amir Amani
Research Article


Highly resistant pathogens may be developed in patients with immune disorders after prolonged exposure to antibiotics, a growing threat worldwide. In order to overcome these problems, this study introduces a new class of engineered nanosystems comprising of tea tree oil nanoemulsion (TTO NE) loaded with Ag nanoparticles (NPs). Silver shows a strong toxicity towards a wide range of microorganisms. Also, TTO NE could be employed as a promising and safe antimicrobial agent for local therapies of bacterial infections. The nanosystem was prepared by low-energy method. Mean droplet size of the NE was found to be 17.7 nm. Results of the antibacterial assays showed promising ability of the designed nanosystem for eradication of Gram-positive and Gram-negative bacteria (95%). Also, it was shown that introducing colloidal Ag NPs to the TTO NE exerted a synergistic effect against Escherichia coli (FIC 0.48) while only an additive effect was observed against Staphylococcus aureus (FIC 0.75). The antibacterial effects of TTO NE+Ag NPs together with their compatibility with human cells can present them as a suitable candidate to fight against the antibacterial resistance threat.


tea tree oil nanoemulsion resistant bacteria silver nanoparticle synergism 


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Copyright information

© American Association of Pharmaceutical Scientists 2017

Authors and Affiliations

  • Roqya Najafi-taher
    • 1
  • Behnaz Ghaemi
    • 1
  • Sharmin Kharazi
    • 1
  • Samira Rasoulikoohi
    • 1
    • 2
  • Amir Amani
    • 1
    • 3
  1. 1.Department of Medical Nanotechnology, School of Advanced Technologies in MedicineTehran University of Medical SciencesTehranIran
  2. 2.Antimicrobial Resistance Research Center, Rasoul-e-Akram HospitalIran University of Medical SciencesTehranIran
  3. 3.Medical Biomaterials Research Center (MBRC)Tehran University of Medical SciencesTehranIran

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