Search for: cetyltrimethylammonium-bromide
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    Graphene oxide for rapid determination of testosterone in the presence of cetyltrimethylammonium bromide in urine and blood plasma of athletes

    , Article Materials Science and Engineering C ; Volume 61 , 2016 , Pages 246-250 ; 09284931 (ISSN) Heidarimoghadam, R ; Akhavan, O ; Ghaderi, E ; Hashemi, E ; Mortazavi, S. S ; Farmany, A ; Sharif University of Technology
    Electro-reduction behavior of testosterone at reduced graphene oxide/glassy carbon electrode (rGO/GCE) was studied. Cationic surfactant cetyltrimethylammonium bromide (CTAB) enhanced the reduction peak of testosterone. In borate buffer (pH 5.4) CTAB-testosterone showed a reduction peak at - 1.1 V (versus, Ag/AgCl). The increment of peak current obtained by deducting the reduction peak current of the CTAB-testosterone was rectilinear with testosterone concentration in the range of 2.0 to 210.0 nM, with a detection limit of 0.1 nM. The sensor was used for quantification of testosterone in biological fluids and drug  

    Preconcentration and determination of pantoprazole by solid-phase extraction coupled with spectrophotometry using iron oxide nanoparticles modified with cetyltrimethylammonium bromide

    , Article Nano Biomedicine and Engineering ; Volume 7, Issue 3 , 2015 , Pages 102-110 ; 21505578 (ISSN) Sayyahmanesh, M ; Naghian, E ; Sahebi, H ; Asgari, S ; Sharif University of Technology
    Open Access House of Science and Technology  2015
    Solid phase extraction coupled with spectrophotometric detection was applied to trace amounts of Pantoprazole (PP) drug using Cetyltrimethylammonium bromide coated-iron oxide magnetite nanoparticles CTAB@Fe3O4 MNPs. After characterization of the prepared nano-adsorbents, experimental parameters affecting the extraction efficiency of the developed method were optimized. The results obtained showed that this proposed approach is applicable in concentrations ranging from 0.1 to 1.5 μg/ml (R2 = 0.9958) indicating that follows Beer's-Lambert law. The limit of detection and the limit of quantification calculated to be 0.014 and 0.04 μg/ml, respectively. The repeatability of the proposed method was... 

    Enhanced hardness and corrosion resistance of Zn/SiO2 films by electrodeposition

    , Article Journal of the Electrochemical Society ; Volume 162, Issue 9 , 2015 , Pages D480-D485 ; 00134651 (ISSN) Ghorbani, M ; Salehi, F ; Razavizadeh, O ; Sharif University of Technology
    Electrochemical Society Inc  2015
    The electrodeposition of Zn-SiO2 nanocomposites has been investigated with different electrolytes: triethanolamine as a dispersing agent, and cetyl trimethylammonium bromide and dodecyl dimethylamine oxide as ionic (cationic) and non-ionic surfactants. Appropriate electrophoretic potentials for each solution were obtained using cyclic voltammetry. The results show that the most stable SiO2 nanoparticles with zeta potential range of 25 to 41 mV, along with highest SiO2 mobility of 0.4 to 0.7 m2/V.s were dispersed by triethanolamine in ethanol and the resulting coating adhesion improved up to 5.87 MPa in the standard pull off test, with the enhanced hardness of... 

    A smart-phone based ratiometric nanoprobe for label-free detection of methyl parathion

    , Article Sensors and Actuators, B: Chemical ; Volume 322 , 2020 Fahimi Kashani, N ; Hormozi Nezhad, M. R ; Sharif University of Technology
    Elsevier B.V  2020
    The widespread use of pesticides in pest management has boosted the demands for developing highly sensitive probes for on-site monitoring. Herein we presented a sensitive enzyme-free ratiometric probe for determination of methyl parathion (MP), as an organophosphate pesticide using TGA-capped CdTe QDs and carbon dots (CDs). Unlike previous methods in which hydrolysis product of MP is instrumental in the response of the sensors, here, self-assembly of cetyltrimethylammonium bromide (CTAB) on the surface of non-modified yellow-emissive CdTe QDs facilitates the quenching of CTAB-QDs upon addition of MP while the fluorescence intensity of CDs remains constant. Using a smartphone, the ratiometric... 

    Polypyrrole nanowires network for convenient and highly efficient microextraction in packed syringe

    , Article Analytical Methods ; Volume 3, Issue 11 , 2011 , Pages 2630-2636 ; 17599660 (ISSN) Bagheri, H ; Ayazi, Z ; Sharif University of Technology
    A novel method based on microextraction in packed syringe (MEPS), as a sample preparation technique in combination with gas chromatography-mass spectrometry (GC-MS) was developed using a polypyrrole (PPy) nanowires network as the extracting medium. The PPy nanowires network was prepared using a soft template technique and its characterization was studied by scanning electron microscopy (SEM). The use of micelles in this methodology has an important role in the shape of the growing polymer. The pyrrole monomer was introduced into cetyltrimethylammonium bromide (CTAB) micelles and this has led to the formation of nanowires with diameters ranging from 30 to 60 nm. The bulk PPy prepared without... 

    Rheology, stability and filtration characteristics of colloidal gas aphron fluids: role of surfactant and polymer type

    , Article Journal of Natural Gas Science and Engineering ; Volume 26 , September , 2015 , Pages 895-906 ; 18755100 (ISSN) Tabzar, A ; Arabloo, M ; Ghazanfari, M. H ; Sharif University of Technology
    Elsevier  2015
    Colloidal Gas Aphron (CGA) are finding increasing application in fields of science and engineering because of their distinctive characteristic. As interest in the application of CGA based fluids grows and in order to select the best procedure for using them in successful petroleum engineering operations, there is a need to gain a better understanding of the factors that affect their properties and behavior. This article discusses the rheological characterization, stability analysis and filtration properties of CGA based fluids for three bio-polymers and two ionic surfactant. The stability and filtration analysis were investigated with the static drain rate technique and API filtration tests,... 

    Equilibrium, kinetic and thermodynamic studies of a low-cost biosorbent for the removal of Congo red dye: Acid and CTAB-acid modified celery (Apium graveolens)

    , Article Journal of Molecular Structure ; Volume 1176 , 2019 , Pages 181-193 ; 00222860 (ISSN) Mohebali, S ; Bastani, D ; Shayesteh, H ; Sharif University of Technology
    Elsevier B.V  2019
    This study introduces a new and bio-friendly adsorbent based on natural and cetyltrimethylammonium bromide (CTAB) modified adsorbent, celery (Apium graveolens) residue for removal of organic pollutants. The adsorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and pHpzc techniques. Removal applicability and efficiency of this biosorbent were studied using Congo red (CR) as a sample organic pollutant. To reach the best results, main parameters such as pH, adsorbent mass, contact time, initial dye concentration and temperature were optimized through the adsorption experiments in a batch system. The kinetic and isotherm of CR removal... 

    Surfactant-assisted synthesis and characterization of hydroxyapatite nanorods under hydrothermal conditions

    , Article Materials Science- Poland ; Volume 27, Issue 4 , 2009 , Pages 961-971 ; 01371339 (ISSN) Salarian, M ; Solati Hashjin, M ; Sara Shafiei, S ; Goudarzi, A ; Salarian, R ; Nemati, A ; Sharif University of Technology
    Hydroxyapatite (HAp) nanorods with uniform morphology and controllable size were successfully synthesized by precipitating Ca(NO3) 24H2O and (NH4)2HPO4 in the presence of cetyltrimethylammonium bromide (CTAB) and polyethylene glycol 400 (PEG 400) as cationic surfactant and non-ionic cosurfactant, respectively, under hydrothermal conditions. The effect of hydrothermal temperature on the composition, morphology and size of HAp particles was studied using X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR) and scanning electron microscopy (SEM). Results revealed that the morphology and size of HAp particles can be effectively controlled by the presence of CTAB and PEG... 

    Template-directed hydrothermal synthesis of dandelion-like hydroxyapatite in the presence of cetyltrimethylammonium bromide and polyethylene glycol

    , Article Ceramics International ; Volume 35, Issue 7 , 2009 , Pages 2563-2569 ; 02728842 (ISSN) Salarian, M ; Solati Hashjin, M ; Shafiei, S. S ; Salarian, R ; Nemati, Z. A ; Sharif University of Technology
    A template-directed synthetic method, using surfactant cetyltrimethylammonium bromide (CTAB) as a template and co-surfactant polyethylene glycol (PEG600) as a co-template under hydrothermal conditions, has been applied to obtain dandelion-like HAp. The morphology, size, crystalline phase, chemical composition, physical characteristics, and thermal behavior of the product were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier ransform infrared spectroscopy (FTIR), induced coupled plasma spectroscopy (ICP), BET (Brunauer, Emmett, and Teller) method, and simultaneous thermal analysis (STA). SEM and TEM... 

    Reinforced polydiphenylamine nanocomposite for microextraction in packed syringe of various pesticides

    , Article Journal of Chromatography A ; Volume 1222 , January , 2012 , Pages 13-21 ; 00219673 (ISSN) Bagheri, H ; Ayazi, Z ; Es'haghi, A ; Aghakhani, A ; Sharif University of Technology
    Reinforced polydiphenylamine (PDPA) nanocomposite was synthesized by oxidation of diphenylamine in 4molL-1 sulfuric acid solution containing a fixed amount of carbon nanotubes (CNTs) in the presence of cetyltrimethylammonium bromide (CTAB). The surface characteristic of PDPA and PDPA/CNT nanocomposites was investigated using scanning electron microscopy (SEM). The prepared PDPA/CNT nanocomposite was used as an extraction medium for microextraction in packed syringe (MEPS) of selected pesticides from aquatic environment. The effect of CNT doping level and the presence of surfactant on the extraction capability of nanocomposite was investigated and it was revealed that when 4% (w/w) of CNT in...