JOURNAL OF ADVANCES IN CHEMISTRY Interested in submitting to this journal? We recommend that you review the About the Journal page for the journal's section policies, as well as the Author Guidelines. Authors need to register with the journal prior to submitting or, if already registered, can simply log in and begin the five-step process. en-US <p>Authors retain the copyright of their manuscripts, and all Open Access articles are distributed under the terms of the&nbsp;<a href="">Creative Commons Attribution License</a>, which permits unrestricted use, distribution, and reproduction in any medium, provided that the original work is properly cited.</p> <p>&nbsp;</p> (Gurdev Singh) (Gurpreet Singh) Thu, 31 May 2018 16:30:56 +0000 OJS 60 Annual Reviewer Acknowledgement <p>The editorial team of the journal would like to thank the reviewers for their work in referring manuscripts during 2018.</p> Kewen Zhao ##submission.copyrightStatement## Fri, 31 Aug 2018 08:08:28 +0000 Optimization of 6-Gingerol Extraction Assisted by Microwave From Fresh Ginger Using Response Surface Methodology <p>The present study investigates optimum conditions for Microwave assisted extraction (MAE) of 6-gingerol. Ginger was dried using a cross flow dryer at 55 ± 2 <sup>0</sup>C for eight hours. Ginger powder was extracted at three different watts (400 W, 500 W, and 600 W), temperatures (50 <sup>0</sup>C, 60 <sup>0</sup>C, 70 <sup>0</sup>C) and time (10, 20, 30 min) for optimum yield.&nbsp; 6-gingerol content was found to be 21.15 ± 0.13 and 18.81 ± 0.15 mg/g in fresh ginger and dried ginger, respectively.&nbsp; Optimized condition obtained by RSM for 6-gingerol was 400 W, 70 <sup>0</sup>C at 10 min extraction time.&nbsp; The results of MAE are expressed by 2-D contour plot and response surface curve by keeping one variable constant which showed highest yield at 600 W, 70 <sup>0</sup>C for 30 min extraction time.&nbsp; Microwave assisted extracts exhibited higher antioxidant activity in comparison with conventional extracts.</p> Vedashree M, Madeneni Madhava Naidu ##submission.copyrightStatement## Wed, 30 May 2018 04:49:06 +0000 Direct Spectrophotometric Determination of Glimepiride in Pure Form And Pharmaceutical Formulations Using Bromocresol Purple <p>A simple, direct and accurate spectrophotometric method has been developed for the determination of Glimepiride (GLM) in pure and pharmaceutical formulations by complex formation with bromocresol purple (BCP). The method involves the formation of a yellow ion-pair complex between BCP with glimepiride at pH&lt;3,8; after reacting GLM with Na<sub>2</sub>CO<sub>3</sub> to give C<sub>24</sub>H<sub>33</sub>N<sub>4</sub>H<sup>+</sup>O<sub>5</sub>NaS which is extracted by chloroform. The formed complex [GLM]:[ BCP] was measured at l<sub>max</sub>&nbsp;418 nm against the reagent blank prepared in the same manner. Variables were studied in order to optimize the reaction conditions. Molar absorptivity (e) for complex was&nbsp; 20600 &nbsp;L.mol<sup>-1</sup>.cm<sup>-1</sup>. Beer’s law was obeyed in the concentration range of&nbsp; 1.226 – 46.608 &nbsp;&nbsp;mg.mL<sup>-1 </sup>in present of 5.0x10<sup>-4</sup> mol/l of BCP with good correlation coefficient (R<sup>2</sup>= 0.9997). The relative standard deviation did not exceed 3.6%. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.15 and 0.46 mg.mL<sup>-1</sup>, respectively. The proposed method was validated for specificity, linearity, precision and accuracy, repeatability, sensitivity (LOD and LOQ)&nbsp; and robustness. The developed method is applicable for the determination of GLM in&nbsp; pure and different dosage forms with average assay of 98.8 to 102.0% and the results are in good agreement with those obtained by the &nbsp;RP-HPLC reference method. &nbsp;</p> Abdul Aziz Ramadan, Souad Zeino ##submission.copyrightStatement## Wed, 04 Jul 2018 05:32:33 +0000 The Electrodeposition rhenium-tellurium alloys from chlorides asides electrolytes. <p>There has been investigated the joint electrodeposition of rhenium with tellur from chlorides electrolyte, by measuring the cycling volt-ampere curves there has been determined the field of potentials, at the presence of which the joint electrodeposition of rhenium with sulphur takes place. It has been shown, that the joint deposition of rhenium with tellur goes with a certain depolarization, besides, the depolarization is caused by the energy emanating along formation of ReTe2 compounds. There was studied the influence of current density, temperature and acidity on the composition and quality of cathode sediments. It was established, that with the rise of current density and the temperature of electrolyte the concentration of rhenium in the alloy increases.</p> Elza Salakhova, D. B. Tagiyev, P. E. Kalantarova, A. M. Asgarova ##submission.copyrightStatement## Wed, 04 Jul 2018 00:00:00 +0000 The Spectroscopic and theoretical investigations of complex formation of (3E,3'E)-7,7'-(carbonylbis(azanediyl))bis(3-(2-(2-hydroxyphenyl)hydrazono)-4-oxo-3,4-dihydronaphthalene-2-sulfonic acid) with metal cations <p>A novel azo-dye&nbsp; was isolated by a diazo-coupling reaction and characterized by the elemental analysis, mass spectra, IR and UV-VIS spectroscopy. The processes of complex formation of H4L with some mono-, bis-, and trivalent metal cations were studied by spectrophotometric titration and theoretical modeling. The NBO effective charge calculations indicate a strong covalent character of the coordination bonds at complexation.</p> Olga Kovalchukova, Mikhael Ryabov, Alexandra Obmenennaya, Nikolai Popandopulo ##submission.copyrightStatement## Tue, 31 Jul 2018 05:54:07 +0000 The Influence of Excipients on the Physicochemical and Biological Properties of a Bactericidal, Labile Ester Prodrug in a Salt Form – A Case Study of Cefetamet Pivoxil Hydrochloride <p>The article presents an innovative approach to a bactericidal drug design based on a cephem prodrug analogue – cefetamet pivoxil hydrochloride. The emergence of cefetamet pivoxil hydrochloride excipient systems (mannitol, hydroxypropyl methyl cellulose, pregelatinised starch, lactose monohydrate, magnesium stearate, <a href="">polyvinylpyrrolidone</a>) caused changes in the physicochemical properties of cefetamet pivoxil hydrochloride. They are significant for planning the development of an innovative pharmaceutical formulation. The biological activity profile of the prodrug was also modified. FTIR spectra were used to study interactions between cefetamet pivoxil hydrochloride and the excipients. The theoretical approach to the analysis of experimental spectra enabled precise indication of cefetamet pivoxil hydrochloride domains responsible for interaction with the excipients. The interactions between cefetamet pivoxil hydrochloride and the excipients resulted in some &nbsp;important physicochemical modifications: acceptor fluid-dependent changes in solubility and the dissolving rate as well as a decrease in the chemical stability of cefetamet pivoxil hydrochloride in the solid state, especially during thermolysis. The interactions between cefetamet pivoxil hydrochloride and the excipients also had biologically essential effects. There were changes in its permeability through artificial biological membranes simulating the gastrointestinal tract, which depended on the pH value of the acceptor solution. Cefetamet pivoxil hydrochloride combined with the excipient systems exhibited greater bactericidal potential against <em>Staphylococcus aureus. </em>Its bactericidal potential against <em>Enterococcus faecalis, Pseudomonas aeruginosa </em>and<em> Proteus mirabilis</em> doubled<em>.</em> The new approach provides an opportunity to develop treatment of resistant bacterial infections. It will enable synergy between the excipient and the pharmacological potential of an active pharmaceutical substance with modified physicochemical properties induced by the drug carrier.</p> Jakub Dzitko, Przemyslaw Zalewski, Daria Szymanowska, Piotr Garbacki, Magdalena Paczkowska, Judyta Cielecka Piontek ##submission.copyrightStatement## Thu, 23 Aug 2018 07:07:46 +0000 Differential Pulse Polarographic Behavior and Quantification of the Flucloxacillin in Pure and Pharmaceutical Dosage Forms Using a Static Mercury Drop Electrode <p>Differential pulse polarographic analysis (DPPA) by using static mercury drop electrode (SMDE) for quantification of flucloxacillin (FLUX) in pure and pharmaceutical dosage forms was studied. The optimum conditions for the polarographic signal were determined and a study was made of the different parameters affecting the electrochemical process. The best definition of the analytical signals was found in Britton–Robinson buffer (0.06 M) at pH 4.0 . Under the optimum conditions, liner calibration graph, I<sub>p</sub>=f(C<sub>FLUX</sub>) was obtained in the concentration ranges of 0.1 mM (0.0494 ?g.mL<sup>-1</sup>) to 26 mM (12.8414 ?g.mL<sup>-1</sup>) at -940 to -1000 mV (versus Ag/AgCl) with relative standard deviations (RSD) did not exceed 2.4% for the concentrations of FLUX (0.0494 ?g.mL<sup>-1</sup>). Regression analysis showed a good correlation coefficient (R<sup>2</sup>=9998) between I<sub>p</sub> and concentration over the mentioned range. The limit of detection (LOD) and the limit of quantification (LOQ) were to be 0.0040 and 0.0120 ?g.mL<sup>-1</sup>, respectively. The proposed method was validated for linearity, precision and accuracy, repeatability, sensitivity (LOD and LOQ), robustness and specificity. The developed method is applicable for the determination of FLUX in pure and different dosage forms in presence a same amount of amoxicillin (AMOX) with average recovery of 99.4 to 102.2 % and the results are in good agreement with those obtained by the HPLC reference method.</p> <p>&nbsp;</p> Abdul Aziz Ramadan, Hasna Mandil, Reham Abu Saleh ##submission.copyrightStatement## Wed, 29 Aug 2018 00:00:00 +0000 Differential Pulse Anodic Stripping Voltammetric Analysis for Determination Selenium (IV) in Bulk and in Dosage Formulations Using Multi-Modified Gold Electrode With a Mixture of O-Phenylenediamine and 2,3-Diaminonaphthalene-Nafion <p>The effect of gold electrode modified with 2,3-Diaminonaphthalene (GEM<sub>DAN</sub>N) or multi-modified or a mixture 2,3-diaminonaphthalene and o-phenylenediamine -nafion (GEM<sub>DAN</sub><sub>-OPDA</sub>N) on determination of selenium (IV) using differential pulse anodic stripping voltammetric analysis (DPASVA) has been studied. Various parameters (electrolyte, deposition time, pulse duration, pulse amplitude, etc.) are affecting determination of the Se(IV) in HClO<sub>4 </sub>(0.2 M) at pH 0.22 were examined. Under the optimum conditions, liner calibration graph, I<sub>p</sub>=f(C<sub>Se4+</sub>), were obtained in the concentration ranges of 5x10<sup>-8</sup> - 1x10<sup>-6</sup> M (3.948 -78.96 ng.mL<sup>-1</sup> ) with relative standard deviations (RSD) 4.2% and detection limit 0.056 ng.mL<sup>-1</sup>, and 1x10<sup>-9</sup> -1x10<sup>-6</sup> M (0.07896 -78.96 ng.mL<sup>-1 </sup>) with relative standard deviations (RSD) 4.9% and detection limit was 0.014 ng.mL<sup>-1</sup> on GEM<sub>DAN</sub>N and GEM<sub>DAN</sub><sub>-OPDA</sub>N, respectively. This method showed a good accumulation efficiency for selenium and good resistance to interferences from metal ions as well as those associated with selenium in pharmaceuticals. The results for the determination of Se<sup>4+</sup> using GEM<sub>DAN</sub><sub>-OPDA</sub>N (multi-modified) were more sensitive (about 50 times) than that obtained using GEM<sub>DAN</sub>N.</p> Abdul Aziz Ramadan ##submission.copyrightStatement## Thu, 01 Nov 2018 15:58:27 +0000 Aspartic Acid as Corrosion Inhibitor of Mild Steel Corrosion Using Weight Loss, Acidimetry and EIS Measurement <p>Corrosion inhibition characteristics of aspartic acid on&nbsp; mild steel corrosion in 0.5 M H<sub>2</sub>SO<sub>4</sub> was investigated using weight loss, acidimetry, and electrochemical impedance spectroscopy (EIS). Analysis of the metal surface morphology, uninhibited and inhibited, was carried out through scanned electron microscope. The results showed that the inhibition efficiency increased with increase in inhibitors concentration and rise in temperature for all methods used. The highest v efficiency of &nbsp;32.36 %, 66.26 % and 80.40 % were obtained for weight loss, acidimetry and EIS, respectively. The low value of efficiency for weight loss compared to other methods should signify the limitation for the method. The increase in efficiency with rise in temperature is a feature of chemical adsorption, which was confoirmed by the value of parameter b of the Adejo-Ekwenchi adsorption isotherm (AEI) model. Values of free energy of adsorption, ?G<sub>ads</sub> were all negative for all the methods, which means the adsorption processes were spontaneous. The heats of adsorption, Q<sub>ads</sub> values were all positive, implying that the processes were endothermic. Values of activation energy were fairly constant, which is an evident to support the proposed chemical adsorption mechanism. The negative sign in the values of entropy of adsorption, ?S<sub>ads</sub> is an indication &nbsp;that the activated complex in the rate-determining step was associative. The data obtained was tested with several isotherms, but found to best fit into the El-Awady, Freundlich and Tempkin adsorption isotherm models<em>.</em></p> Sylvester Obaike Adejo, Stephen Gbaoron Yiase, Joseph Aondoaver Gbertyo, Emmanuel Onah Ojah ##submission.copyrightStatement## Sat, 01 Dec 2018 10:51:02 +0000 The Colloidal Quantum Dots Suitability for Long Term Cell Imaging <p>Fluorescent semiconductor nanoparticles in tree-dimensional quantum confinement, quantum dots (QDs), synthesized in aqueous medium, and functionalized with polyethylene glycol, were used as nonspecific nanosized probes for the long-term imaging of glial cells. <em>In vitro</em> living healthy as well as cancer glial cells were labelled by direct insertion of a small volume of QDs contained in aqueous suspension into the culture wells. A long-term monitoring (over 7 days) of the cells was performed and no evidence of cell fixation and/or damage was observed. Two control groups, healthy and non-healthy glial cells, were used to compare cell viability. During the observation period, labelled cells kept the same behavior compared to non-labelled control samples. To our knowledge, this is the first report of the viability of quantum dots for long-term imaging of living cells. This opens a large range of possibilities related to a better understand of cellular mechanisms, which till now was not achieved by any other fluorescent probe. The study also permitted the observation of two distinct interaction kinetics between cells and QDs. Healthy glial cells were mainly labelled at their surface, while non-healthy glial cells have shown a high rate in the uptake of QDs.</p> Patricia M. A. Farias, André Galembeck, Raquel Milani, Wilson S. Mendonca, Andreas Stingl ##submission.copyrightStatement## Sat, 01 Dec 2018 10:48:36 +0000 Direct Spectrophotometric Determination of Cefuroxime Axetil in Pure Form and Pharmaceutical Dosage Forms. <p>A simple, direct and cost-effective spectrophotometric method for determination of cefuroxime axetil (CRXA) &nbsp;in pure and tablet dosage forms was applied. This method is based on formation of ion-pair complex ([CRXA]:[BTB]) between CRXA and bromothymol blue (BTB) in chloroform. Beer’s law in the optimum experimental conditions using [CRXA]:[BTB] complex is valid within a concentration range of 2.00-50.00 ?M (1.021–25.524 ?g.mL<sup>-1</sup>). The developed method is applied for the determination of CRXA in pure and its commercial tablets without any interference from excipients with average assay of 96.8 to 101.6% and the results are in good agreement with those obtained by the HPLC reference method. Associated drugs (sulbactam and linesolid) with cefuroxime axetil are considered to be interfere, while metronidazole can be considered as non-interfere.</p> Abdul Aziz Ramadan, Hasna Mandil, Abdulrahman Shikh Debes ##submission.copyrightStatement## Sat, 01 Dec 2018 10:51:48 +0000 Adsorption Of No3--N And Po43--P in Aqueous Solution Using Granular Activated Charcoal (Gac) <p>In this study, adsorption of NO<sub>3</sub><sup>- </sup>-N and PO<sub>4</sub><sup>3-</sup>-P on granular activated charcoal (GAC) was investigated depending on pH, agitation time, GAC dosage, adsorption capacity and adsorption isotherms by employing batch adsorption type. The GAC was characterized by thermogravimetric analysis (TG-DTA), scanning electron micrograph coupled with energy-dispersive X-ray spectroscopy (SEM-EDX) and BET surface area analyzer. The GAC exhibited nearly similar adsorption equilibrium time. Both NO<sub>3</sub><sup>-</sup>-N and PO<sub>4</sub><sup>3—</sup>P appeared to approach equilibrium after approximately 4 h of agitation time. In the adsorption equilibrium, the removal efficiencies of NO<sub>3</sub><sup>- </sup>-N and PO<sub>4</sub><sup>3-</sup>-P were found to be 14.6-66.0 % and 52.4-99.0 %, respectively. The adsorption data for NO<sub>3</sub><sup>-</sup>-N and PO<sub>4</sub><sup>3-</sup>-P was correlated to Freundlich and Langmuir isotherm model and the equilibrium data was fitted well to the Langmuir isotherm model due to their higher correlation coefficient (<em>R</em><sup>2</sup>) value. The Langmuir adsorption capacity was 1.54 and 2.56 mg g<sup>-1</sup> for NO<sub>3</sub><sup>-</sup>-N and PO<sub>4</sub><sup>3</sup><sup>-</sup>-P, respectively, which suggests that the GAC is a good adsorbent for removal of NO<sub>3</sub><sup>-</sup>-N and PO<sub>4</sub><sup>3—</sup>P from water.</p> Yong Pyo Hong, Keon Sang Ryoo ##submission.copyrightStatement## Mon, 03 Dec 2018 07:46:42 +0000