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Talebian N.,Islamic Azad University at Shahreza | Kheiri M.,Islamic Azad University at Falavarjan
Solid State Sciences | Year: 2014

Nickel oxide films were deposited onto glass substrates by sol-gel dip coating method using solvents of different polarities without any catalysts, templates or surfactants. Methanol, 1,4-butanediol, ethanol, and 2-propanol were used as solvents. The structural, optical and electrical properties of NiO films were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible spectroscopy and Hall effect measurements, respectively. Nickel oxide thin films with cubic phase crystal structure of various preferred orientations were obtained in the different solvents. The XRD results showed that films deposited from solution using higher polar solvents develop a (1 1 1) preferred orientation, while the (2 0 0)-orientated films were obtained using lower polar solvents. The average particle size increases with viscosity of solvents. Surface morphology of the nickel oxide film consisted of nanoparticles with uniform coverage of the substrate surface. The solvent of higher viscosity induced larger particle size. Band gap narrowing from 4.42 to 3.87 eV was observed using different solvents. The lower resistivity and Hall coefficient was obtained for prepared NiO films using higher polar solvents. The relationships between solvent physicochemical properties, preferred orientation, structural, optical and electrical properties of NiO films were investigated. © 2013 Elsevier Ltd. All rights reserved.


Talebian N.,Islamic Azad University at Shahreza | Amininezhad S.M.,Islamic Azad University at Shahreza | Doudi M.,Islamic Azad University at Falavarjan
Journal of Photochemistry and Photobiology B: Biology | Year: 2013

ZnO materials with different morphologies have been synthesized via a simple solvothermal method using different solvents without any catalysts, templates or surfactants. The ZnO samples are employed in the inactivation of gram-negative Escherichia coli and gram-positive Staphylococcus aureus in MilliQ water. The photocatalytic activities of samples to degrade an azo dye, Acid Orange 74 (CI 18745), were also tested. XRD data showed that single-phase ZnO with the wurtzite crystal structure but different growth habits were obtained in the different solvents. SEM imaging illustrated that ZnO with flower-like, rod-like, and spherical shape were produced when water, 1-hexanol, and ethylene glycol were used as the solvent, respectively. The optical properties of the as-prepared ZnO materials were investigated by UV-vis absorption and photoluminescence spectra. The antibacterial efficiencies were affected by the physiological status of the bacterial cells, different morphologies and crystal growth habits, particle size and optical properties of ZnO samples. Results indicate that ZnO flower-like showed significantly higher photocatalytic inactivation than ZnO rod- and sphere-like against E. coli compared with S. aureus. It was found that the antibacterial activity of ZnO increased with decreasing crystallite size. The inactivation efficiencies for both organisms under light conditions were higher than under dark conditions. The obtained results were discussed according to the morphologies, optical and structural properties of ZnO powders as key parameters in photocatalytic and antibacterial activity. © 2013 Elsevier B.V. All rights reserved.


Fouladgar M.,Islamic Azad University at Falavarjan | Karimi-Maleh H.,Islamic Azad University
Ionics | Year: 2013

Ionic liquid/multiwall carbon nanotubes paste electrode has been used as a novel sensor for the efficient quantitative determination of methyldopa (MDOP) in pharmaceutical and biological samples by using square wave voltammetry. This new sensor shows a better electrochemical response with lower over-potential and high sensitivity for MDOP compared with unmodified carbon paste electrode in physiological condition. The electro-oxidation of MDOP occurred in a pH-dependent 2e- and 2H+ process, and the electrode reaction followed a diffusion-controlled pathway. Under the optimum conditions, the voltammetric oxidation peak current of MDOP showed two linear dynamic ranges with a detection limit of 0.1 μM for MDOP. The novel sensor has been found selective and successfully implemented for the determination of MDOP in real samples such as tablet and patient urine. © 2012 Springer-Verlag Berlin Heidelberg.


Momtaz H.,Islamic Azad University | Yadollahi S.,Islamic Azad University at Falavarjan
Diagnostic Pathology | Year: 2013

Background: Among all species of Listeria, Listeria monocytogenes (L. monocytogenes) is a major pathogenic microorganism of humans and animals and L. ivanovii is rarely pathogenic for humans. The objective of this study was to isolate and characterize Listeria species and to determine the frequencies of virulence genes in L. monocytogenes serotypes in fresh fish, shrimp, crab and lobster in Isfahan and Shahrekord, Iran. Methods: From September 2010 to April 2011, a total of 300 marine food samples were purchased from supermarkets of Isfahan and Shahrekord cities, Iran. All samples were cultured and the positive samples for L. monocytogenes were analyzed for presence of serotypes and virulence genes. Results: From the total 300 samples, 23 (10.45%) fresh fish and 1 (2.5%) shrimp samples were positive for Listeria spp., but there were no positive lobster and crab samples for Listeria species. Only L. monocytogenes was isolated from 17 fish (7.25%) and 1 shrimp (2.5%) samples while L. innocua, L. ivanovii and L. seeligeri only detected in fish samples (2 (0.9%), 3 (1.36%) and 1 (0.45%)), respectively. The plcA, prfA, actA, hlyA and iap virulence genes were detected in all of the 18 L. monocytogenes isolates. Totally, the 4b, 1/2a and 1/2b serotypes were detected in 66.66%, 5.55% and 27.77% bacterial isolates, respectively. Conclusions: Consumption of these sea foods, either raw or undercooked, may contribute to food-borne illness due to L. monocytogenes in Iran. The hygienic quality of sea food products should be observe.Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3422944359800606. © 2013 Momtaz and Yadollahi; licensee BioMed Central Ltd.


Fouladgar M.,Islamic Azad University at Falavarjan
International Journal of Electrochemical Science | Year: 2011

A new sensitive and selective electrochemical sensor was developed for determination of captopril (CAP) in tablet and human patient urine. Captopril is an inhibitor of the angiotensin-converting enzyme and is widely used for the treatment of hypertension and congestive heart failure. A voltammetric study of captopril has been carried out at the surface of carbon paste electrode modified with multi-wall carbon nanotubes as a sensor and ferrocene as a mediator. The electrochemical oxidation of captopril was investigated by chronoamperometry, cyclic and differential pulse voltammetric techniques. The dependence of peak currents on pH, concentration and the potential scan rate was investigated. Two linear dynamic ranges of 0.5-12 μM and 12-300 μM with a detection limit of 0.15 μM was obtained in phosphate buffer of pH = 9. Differential pulse voltammetry as a simple, rapid, sensitive and selective method was developed for the determination of captopril in tablet and human urine without any treatments. © 2011 by ESG.


Emami-Karvani Z.,Islamic Azad University at Falavarjan | Chehrazi P.,Islamic Azad University at Falavarjan
African Journal of Microbiology Research | Year: 2011

The aim of the present study is to determine the antimicrobial activity of ZnO nanoparticles against Gram-negative and Gram-positive bacteria. Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were used as test microorganisms. The effects of particle size and concentration on the antibacterial activity of ZnO nanoparticles was studied using bacteriological tests such as disc and well diffusion agar methods, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). These tests were performed in nutrient broth and nutrient agar following standard methods. In addition, the effect of different concentrations of ZnO nanoparticles on the growth of E. coli and S. aureus was measured with respect of time. The minimum inhibitory concentration was determined using seven different concentrations of ZnO nanoparticles including 16, 8, 4, 2, 1 and 0.5 mg/ml. The MIC value for E. coli and S. aureus was 1 and 0.5 mg/ml, respectively. The results showed that ZnO nanoparticles have antibacterial inhibition zone of 29 and 19 mm at the concentration of 10 mg/ml against E. coli and S. aureus, respectively. Gram-negative bacteria seemed to be more resistant to ZnO nanoparticles than Gram-positive bacteria. It was found that the antibacterial activity of ZnO nanoparticles increased with decreasing particle size and increasing powder concentration. The antibacterial effect of ZnO nanoparticles was time dependent and takes effect gradually. ZnO bulk powder showed no significant antibacterial activity. © 2011 Academic Journals.


Fouladgar M.,Islamic Azad University at Falavarjan
Journal of the Electrochemical Society | Year: 2016

The aim of this work was using ZnO nanoparticles and a synthesized ion liquid (1-Methyl-3-butylimidazolium bromide) for modification of carbon pate electrode. This modified electrode was applied to determination of isoproterenol (IP). Under optimum pH of 7.0, the oxidation of IP in the presence of ZnO nanoparticles and ion liquid occurred at a potential about 520 mV and oxidation current was more than unmodified electrode. Square wave voltammetry was used for determination of linear dynamic range of the method. The plot of oxidation current vs. concentration was linear in the range of 0.08 to 800.0 μmol L-1IP and detection limit was calculated to be 0.04 μmol L-1 IP. The diffusion coefficient (D = 2.9 × 10-6cm2s-1), and electron transfer coefficient (α = 0.78) for IP were also determined using electrochemical approaches. This method was also examined for determination of IP in pharmaceutical and biological samples. © 2015 The Electrochemical Society. All rights reserved.


Fouladgar M.,Islamic Azad University at Falavarjan
Measurement: Journal of the International Measurement Confederation | Year: 2016

In this work, ZnO nano particles were synthesized and their characteristics were investigated by scanning electron microscopy and X-ray powder diffraction. ZnO nano particles and a synthesized ionic liquid (1-Methyl-3-butylimidazolium bromide) were applied to modification of carbon paste electrode. Electrochemical behavior of benserazide (BA) was studied at modified electrode. Under optimum pH of 6.0, the relation between oxidation current and concentration of BA was linear in the range of 0.1-430.0 μmol L-1 BA. Detection limit of method was calculated to be 0.06 μmol L-1 BA. Effects of potential interferences on determination of BA were investigated and proposed method was used for determination of BA in biological samples. © 2016 Elsevier Ltd. All rights reserved.


Antimicrobial resistance in hospital pathogens is an important concern. It can cause longer hospital stays, increase costs, and contribute to increased mortality and morbidity in hospitalized patients. The aim of this study was to categorize and identify gram-negative bacilli capable of ESBLs production and to study the effect of MIC silver nanoparticles on bacteria strains and then study them in Wistar rats. A total of 186 clinical samples in 3 hospital of Isfahan city was studied during 8 months. The ESBL assay was performed by disk diffusion method. Minimum inhibitory concentration (MIC) values were determined by agar dilution method. Additionally, ESBLs production was examined by using the standard ESBL disc and DDT (double disk approximation test) procedures. Student's T-test and ANOVA were used for statistical analysis of the data. The ESBL-producing bacteria were then subjected to minimum concentrations of silver nanoparticles and then examined in Wistar rats. Of the 186 patients studied, 140 (75.3%) had gram-negative bacilli containing ESBL and 46 (24.7%) had gram-negative bacilli without ESBL and the most prevalent bacteria was identified as Klebsiella pneumonia, with especially strong resistance to cefotaxime. All of these bacteria were sensitive to the silver nanoparticle solution with density of 100 ppm, but the 4 nm size did not show any significant difference from control group Wistar rats at 6 months. The results seem to indicate a direct correlation between silver nanoparticle solution concentration and the diameter of growth zone for ESBL-producing bacteria. Assays in our study were in vitro; if use of silver nanoparticle particles in vivo proves to be with adverse effects, it could be a valuable alternative to antibiotics.


Fouladgar M.,Islamic Azad University at Falavarjan
Sensors and Actuators, B: Chemical | Year: 2016

Using a NiO/functional single walled carbon nanotubes nanocomposite incorporated with ionic liquid (IL/NiO/CNT/CPE), we prepared a sensitive and selective sensor for determination of nalbuphine (NA). Nalbuphine is a semi-synthetic analgesic drug. Electrochemical investigations showed that the nanocomposite had catalytic effect on oxidation of nalbuphine and enhanced the oxidation current. This modified electrode had linear dynamic range from 0.2 to 500.0 μmol L-1 NA with detection limit of 0.07 μmol L-1 NA. Selectivity of the sensor has been studied and proposed method has been applied for determination of nalbuphine in biological samples. © 2016 Elsevier B.V. All rights reserved.

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