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Investigation of the Interaction between Nitrite Ion and Bovine Serum Albumin Using Spectroscopic and Molecular Docking Techniques 下载免费PDF全文
The interaction between nitrite ion and bovine serum albumin (BSA), in an aqueous environment, was studied using spectroscopic methods, including fluorescence quenching technique, synchronous fluorescence, UV? Vis spectrophotometry and Resonance Rayleigh Scattering (RRS), and molecular docking technique. The experimental results showed that nitrite ion effectively quenched the intrinsic fluorescence of BSA with the static quenching. The ion‐BSA binding constant was determined to be 3.69×103 L mol?1. As the results showed the stoichiometry of binding nitrite ion to BSA was 1 : 1. Furthermore the thermodynamic parameters and nature of the binding force were calculated. The negative ΔHo and ΔSo values of reaction between nitrite ion and BSA indicated the predominant forces in the ion‐BSA interactions are hydrogen bonding interactions. Based on the Förster’s theory of non‐radiative energy transfer, the binding distance between nitrite ion and the inner tyrosine and tryptophan residue of BSA were determined to be 2.16 nm. Furthermore binding site of this ion on BSA was carried out by molecular docking technique. 相似文献
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Construction and Application of an Electrochemical Sensor for Simultaneous Determination of Cd(II), Cu(II) and Hg(II) in Water and Foodstuff Samples 下载免费PDF全文
Abbas Afkhami Razieh Moosavi Tayyebeh Madrakian Hassan Keypour Ameneh Ramezani‐Aktij Misagh Mirzaei‐Monsef 《Electroanalysis》2014,26(4):786-795
By incorporation of synthesized magnetite nanoparticles (Fe3O4 NPs) coated with a new Schiff base into carbon paste electrode, a novel modified electrode was constructed for simultaneous determination of ultra trace amounts of Cd(II), Cu(II) and Hg(II). The complexation reaction of Schiff base with metal ions was studied spectrophotometrically. Under optimal conditions a detection limit of 0.20, 0.90 and 1.00 ng mL?1 for Cd(II), Cu(II) and Hg(II), respectively, was obtained. We take the advantages of the proposed method for simple, rapid, sensitive and selective simultaneous determination of trace amounts of hazardous Cd(II), Cu(II) and Hg(II) in water and foodstuff samples. 相似文献
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Kohestani Tayyebeh Sayyed-Alangi S. Zahra Hossaini Zinatossadat Baei Mohammad T. 《Molecular diversity》2022,26(3):1441-1454
Molecular Diversity - In this research we investigated the preparation of new (5Z, 8Z)-7H-pyrido[2,3-d]azepine derivatives in high yields via multicomponent reaction of isatins, alkyl bromides,... 相似文献
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Masoud Shariati‐Rad Mohsen Irandoust Tayyebeh Amini Mojtaba Shamsipur 《Journal of Chemometrics》2013,27(3-4):63-69
For simultaneous determination in conditions with spectral overlap and variation of matrix effects, coupling of the generalized standard addition method (GSAM) with the multivariate nonlinear method of radial basis function–partial least squares (RBF–PLS) was proposed. The nonlinearity caused by the GSAM used to correct matrix effects was studied, and principal component analysis was proposed for identifying it. In the method introduced, the whole sensor range can be used without the collinearity problem encountered in the application of GSAM with classical least squares (CLS), and calibration can be made for each analyte, separately. The introduced method was applied to determine amlodipine and atorvastatin in urine samples. The mean of the percent recoveries was between 95 and 101.12. The percent relative standard deviation values of the method were in most cases below 5%. The results of GSAM–RBF–PLS were compared with those obtained by GSAM–CLS and GSAM–PLS. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Tayyebeh Madrakian Somayeh Maleki Abbas Afkhami 《Journal of the Iranian Chemical Society》2016,13(10):1819-1825
In the present study a glassy carbon electrode, modified with nanocomposite of gold nanoparticles/multiwalled carbon nanotubes (GNPs/MWCNTs/GCE), was used for determination of dicyclomine hydrochloride (DcCl). The results showed that synergetic effects of GNPs and MWCNTs highly improved electrochemical response and sensitivity of the sensor. The electrochemical oxidation of DcCl was investigated by cyclic voltammetry and differential pulse voltammetry. Also, scanning electron microscopy and energy dispersive x-ray spectroscopy were used to evaluate microstructure of electrochemical sensor. The effect of various experimental parameters including pH and scan rate on the voltammetric response of DcCl were investigated. Under the optimal conditions linear response was observed in range of 1.0–1.2 × 102 µmol L?1 for DcCl. The lower detection limit was found to be 0.40 µmol L?1 for DcCl. The investigated method showed good stability, reproducibility and repeatability. The proposed sensor was successfully applied to the determination of DcCl in real samples. 相似文献
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A water-accelerated multicomponent synthesis of organic target molecules has been used as a key method for the preparation of novel barbiturate derivatives. The three-component condensation reactions of primary amines with alkyl propiolates in the presence of alloxan derivatives in water are developed as efficient and clean green synthetic procedures for the high-yielding preparation of alkyl 2-(5-hydroxy-2,4,6-trioxohexahydro-5-pyrimidinyl)-3-(alkyl or arylamino)-2-propenoates. The above synthetic protocol provides rapid access to novel and diversely substituted barbiturate derivatives. 相似文献
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Abbas Afkhami Mohammad Saber-Tehrani Hasan Bagheri Tayyebeh Madrakian 《Mikrochimica acta》2011,173(3-4):543-545
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Mohammad M. Khodaei Abdolhamid Alizadeh Tayyebeh Kanjouri 《Journal of heterocyclic chemistry》2013,50(1):23-28
A series of novel catechol‐fused tetracyclic compounds, with an imidazo[2,1‐b]thiazole central core, were successfully synthesized through the anodic oxidation of catechols in the presence of 2‐mercaptobenzimidazole in aqueous solution. The cyclic voltammetric results indicate that a one‐pot four‐step sequential reaction occurs between 2‐mercaptobenzimidazole and the electrochemically derived o‐benzoquinones affording fused polyheterocyclic compounds. The mechanism of this catalyst‐free, domino reaction is proved as an ECEC pathway using controlled‐potential coulometry. In addition, the electrosyntheses of fused compounds have been successfully performed in ambient conditions in an undivided cell using an environmentally friendly method with high atom economy. The structures of products were characterized by FT‐IR, 1H NMR, 13C NMR, and HRMS spectrometric methods. 相似文献
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A cloud point extraction process using mixed micelle of the cationic surfactant CTAB and non-ionic surfactant TritonX-114 to extract uranium(VI) from aqueous solutions was investigated. The method is based on the color reaction of uranium with pyrocatechol violet in the presence of potassium iodide in hexamethylenetetramine buffer media and mixed micelle-mediated extraction of complex. The optimal extraction and reaction conditions (e.g. surfactant concentration, reagent concentration, effect of time) were studied and the analytical characteristics of the method (e.g. limit of detection, linear range, preconcentration, and improvement factors) were obtained. Linearity was obeyed in the range of 0.20-10.00 ng mL−1 of uranium(VI) ion and the detection limit of the method is 0.06 ng mL−1. The interference effect of some anions and cations was also tested. The method was applied to the determination of uranium(VI) in tap water, waste-water and well water samples. 相似文献