Reference Values of Oxidative Stress Parameters in Adult Iranian Fat-Tailed Sheep

The present study was performed on 111 adult clinically healthy Iranian fat-tailed sheep from both sexes (28 male and 83 female). Blood concentrations of oxidative stress parameters viz. malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) were determined. The reference values for oxidative stress parameters of adult clinically healthy Iranian fat-tailed sheep were as followed: MDA 0.53-0.60 mmol/l, SOD 948.65-1011.50 U/gHb, CAT 1834.29-1915.63 U/gHb and GPX 191.67-196.52 U/gHb. There were no significant differences in oxidative stress parameters among animal of the two sexes

Construction and characterization of a theranostic system based on graphene/manganese chelate

Construction of hybrid systems that combine the cancer treatment and diagnosis agents on a single platform, known as theranostic systems, have received great attentions in the field of nanobiomedicine. Here, construction and characterization of a new multifunctional hybrid theranostic system based on RGO, PDA, BSA, DTPA-Mn(II), and MTX constituents, is presented. Accordingly, GO is partially reduced and simultaneously functionalized by dopamine, leading to reduced graphene oxide/polydopamine, RGO-PDA system; and then, the bovine serum albumin protein (BSA) is grafted onto this system. The obtained system, RGO-PDA-BSA, is further decorated with diethylenetriaminepentaacetic acid-Mn(II) as diagnostic system and methotrexate as anticancer drug. Physicochemical characteristics of the RGO-PDA-BSA-DTPA-Mn(II)/MTX system are studied by Fourier transform infrared spectroscopy, atomic force microscopy, and electrochemical methods. The capturing ability of the prepared system for the cancer cells is evaluated through electrochemical impedance spectroscopy (EIS) and by using the 4T1 cancer cells in comparison with L929 normal cells. The EIS results indicate that a degree of selectivity as 6.23 for GC-RGO-PDA-BSA-DTPA-Mn(II)/MTX electrode system toward 4T1 cells, which is larger than that obtained for this system toward the L929 cells. Similar analysis performed using the GC-RGO-PDA-DTPA-Mn(II)/MTX system (having no BSA) indicate that the selectivity degree of the system is increased only by a factor of 1.6, implying that presence of BSA has increased the selectivity of the system for 4T1 cells by a factor of four. This behavior supports the crucial role of BSA in this process for 4T1 cells. Finally, the drug release study of RGO-PDA-BSA-DTPA-Mn(II)/MTX system is performed successfully at pH 7.4

Corrosion Protection Effect of Chitosan on the Performance Characteristics of A6063 Alloy

This article outlines the behaviour of water-soluble chitosan as an effective inhibitor on aluminium alloy in 3.65% NaCl at room temperature. The inhibitive ability of water-soluble chitosan was examined using electrochemical potentiodynamic polarization techniques, mass loss measurements and computational studies. The outcome of the experiment reveals that chitosan inhibited aluminium alloy in sodium chloride solution exhibits better corrosion protection than the uninhibited because chitosan nanoparticles minimize the ingression of chloride ion into the active sites of aluminium alloy by forming thin film on its surface. The losses in mass by the inhibited aluminium alloy were found to reduce as the concentration of chitosan increases. Results obtained showed that chitosan could offer inhibition efficiency above 70%. Polarization curve demonstrated that chitosan in 3.65% NaCl at room temperature acted as a mixed-type inhibitor. Adsorption of chitosan nanoparticles on the aluminium alloy was found to follow Langmuir adsorption isotherm with correlation regression coefficient (R2 ) value of 0.9961

Microwave-assisted synthesis and characterization of bimetallic PtRu alloy nanoparticles supported on carbon nanotubes

Abstract Multiwalled carbon nanotube (MWCNT) supported PtRu nanoparticles were synthesized by using a microwave-assisted improved impregnation technique. X-ray diffraction, transmission electron microscopy and X-ray photo electron spectroscopy were used to characterize the prepared PtRu/MWCNT nanoparticles. The PtRu nanoparticles with a satisfactory dispersion were formed on the external surface of MWCNTs. The CO stripping experiment was performed to evaluate the poisoning resistance of the prepared PtRu/MWCNT nanoparticles. Results of electrochemical measurements indicate that the prepared PtRu/MWCNTs shows an enhanced performance toward CO poisoning. The results of characterization revealed that microwave-assisted improved impregnation technique have a high yield of alloy phase formation and could be effectively used as a simple, quick and efficient technique for preparation of bimetallic PtRu/MWCNT nanoparticles. © 2015 Elsevier B.V.

Synthesis of multiwall carbon nanotubes with a high loading of Pt by a microwave-assisted impregnation method for use in the oxygen reduction reaction

A multiwall carbon nanotube (MWCNT) catalyst with a high loading (40 wt.%) of platinum was syn-thesized by a microwave-assisted improved impregnation method. The catalyst nanoparticles werecharacterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spec-troscopy. Results of physicochemical characterizations reveal that the catalyst is uniformly loaded onthe external surface of the MWCNTs with a relatively narrow particle size distribution (an average of3.9 nm). The electrocatalytic performance of the catalyst toward oxygen reduction was studied by lin-ear sweep voltammetry measurements of a catalyst-coated rotating disk electrode at different rotationrates. The results show that the prepared catalyst has good electrocatalytic activity for oxygen reductionfollowing a four-electron path to produce water molecules. © 2013 Elsevier Ltd. All rights reserved.

Preparation of Highly Active 40?wt.% Pt on Multiwalled Carbon Nanotube by Improved Impregnation Method for Fuel Cell Applications

40 wt.% Pt catalyst supported on multiwalled carbon nanotube (MWCNT) was successfully synthesized by using improved aqueous impregnation method. Catalysts were characterized by HR-TEM, XRD, and X-Ray photoelectron spectroscopy. Electrocatalytic performance of the catalyst materials was investigated by electrochemical half cell test measurements. According to the results of electrochemical measurements, synthesized Pt/MWCNT catalyst presented high electrochemical activity which is mostly due to high utilization of catalyst particles and good physical properties of MWCNT supporting material. It was revealed that, improved aqueous impregnation method has a satisfactory efficiency for production of Pt/MWCNT catalyst. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA,Weinheim.

Synthesis and electrocatalytic performance of high loading active PtRu multiwalled carbon nanotube catalyst for methanol oxidation

Multiwalled carbon nanotube (MWCNT) supported PtRu catalyst was prepared by improved aqueous impregnation method. The catalyst nanoparticles were characterized by using high resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. According to the results of physicochemical characterization, PtRu alloy nanoparticles with low content of surface oxidation states were successfully synthesized on the outer surface of MWCNT supporting materials. Electrocatalytic activity of catalyst materials was investigated by using electrochemical half cell and CO stripping analyses. Results of electrochemical measurements indicate that the prepared PtRu/MWCNT catalyst shows an enhanced electrochemical activity toward methanol oxidation and a high electrocatalytic activity for CO oxidation. It is believed that superior performance of the PtRu/MWCNT catalyst is mostly attributed to the high degree of alloy formation and low contents of oxidized species of Pt and Ru. © 2012 Elsevier Ltd. All rights reserved.