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Saadat M.,University of Tehran | Mohammadi S.R.,Tarbiat Modares University | Eskandari M.,Nanomaterial Research Group
Biosciences Biotechnology Research Asia | Year: 2013

In this study antimicrobial activity of ZnO nanoparticles and TiO 2 nanoparticles on the most common pathogen bacterium Pseudomonas aeruginosa was evaluated. P. aeruginosa is one of the prevalent pathogen that caused nosocomial infection. It is generally multi-drug resistant. Pseudomonas aeruginosa (ATCC 27853) were cultured on nutrient agar medium (NA) for 24h at 37°C. TiO2 and ZnO nanoparticles was synthesized from TiCl 4 and : Zinc acetate dehydrate after several steps, and the type and size of these particles were characterized by scanning electron microscopy (SEM) and X-Ray-: Diffraction (XRD). The microbial suspension with concentration of 1×106 cells/ml was prepared. Minimum Inhibitory Concentration (MIC) for TiO2 and ZnO was measured.This present study showed that synthesized ZnO and TiO2 nanoparticles can limit and prevent the growth of Pseudomonas aeruginosa.

Abdoli Yazdi N.,Islamic Azad University at Yazd | Arefi M.R.,Islamic Azad University | Mollaahmadi E.,Islamic Azad University | Abdollahi Nejand B.,Nanomaterial Research Group
Life Science Journal | Year: 2011

In this study, research has been done on the compressive and tensile strength of cement mortar containing Fe2O3 nanoparticles in the amounts of 1, 3 and 5 percent by weight of cement. The results show that the mechanical properties of samples containing 1 and 3 percent Fe2O3 nanoparticles are desirable than the ordinary cement mortar. SEM study about the micro structure of cement mortar containing nanoparticles and ordinary cement mortar showed that Fe2O3 nanoparticles fills the pores completely and reduces the large crystals of Ca(OH)2 and the hydrate products are denser and compact. The mechanical properties results showed that by increasing Fe2O3 nanoparticles to 5 percent reduces the mechanical properties.

Sadjadi S.,University of Tehran | Eskandari M.,Nanomaterial Research Group
Ultrasonics Sonochemistry | Year: 2013

ZnO nanorods have been successfully used as an efficient, economic, and reusable catalyst for the synthesis of imidazo[1,2-a]azine under ultrasonic irradiation. This procedure offers advantages in terms of higher yields, short reaction times and mild reaction conditions. © 2012 Elsevier B.V. All rights reserved.

Eskandari M.,Nanomaterial Research Group | Haghighi N.,University of Tehran | Ahmadi V.,Tarbiat Modares University | Haghighi F.,Tarbiat Modares University | Mohammadi S.R.,Tarbiat Modares University
Physica B: Condensed Matter | Year: 2011

In this study, we have investigated the antifungal activity of ZnO nanorods prepared by the chemical solution method against Candida albicans. In the study, Zinc oxide nanorods have been deposited on glass substrates using the chemical solution method. The as-grown samples are characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). X-ray diffraction (XRD) showed zinc oxide nanorods grown in (0 0 2) orientation. The antifungal results indicated that ZnO nanorod arrays exhibit stable properties after two months and play an important role in the growth inhibitory of Candida albicans. © 2010 Elsevier B.V.All rights reserved.

Haghighi F.,Tarbiat Modares University | Mohammadi S.R.,Tarbiat Modares University | Mohammadi P.,Alzahra University | Eskandari M.,Nanomaterial Research Group | Hosseinkhani S.,Tarbiat Modares University
Bratislava Medical Journal | Year: 2012

Lots of Candida albicans infections involve in biofilm formation on medical devices. This kind of biofilm can impede antifungal therapy and complicates the treatment of infectious diseases particularly in field of chronic diseases associated with implanted devices. This study has investigated the influence of treating silicone catheter, PVC and glass coated with Titanium dioxide (TiO2) nanoparticles on attachment of C. albicans. In this study TiO2 nanoparticles were synthesized from precursor TiCl4 and characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) which showed TiO2 nanoparticles are 70-100 nm in size. In the simplest model of biofilms formation, C. albicans isolates (ATCC10231) and (ATCC 76615) were grown on the surface of small disks of catheter, PVC and glass in a flat-bottomed 12-well plates and evaluated biofilm formation using ATP bioluminescence and tetrazolium salt (XTT) reduction assays. In addition, morphology of C. albicans biofilms after 48 h incubation was observed by SEM. Results indicated that there is a statistical difference between mean of coated samples especially catheter and glass before and after TiO2 nanoparticles coating (p<0.05). In SEM analysis, C. albicans biofilm was more aggregated on the surface of glass and catheter than PVC and control groups and after treatment by these nanoparticles, catheter and glass both showed most significant decrease of C. albicans attachment in comparison to the control groups.

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