Cyclic Voltammetric studies of calcium acetate salt with Methylene blue (MB) Using Gold Electrode |
Author : M Eldefrawy; Essamhassan G Arafa Gomaa; Shereen Salem; Fatma Abdel Razik |
Abstract | Full Text |
Abstract : Abstract Cyclic Voltammetric studies of calcium acetate salt [Ca(CH3COO)2] in absence or presence of Methylene blue (MB) were performed to predict and analyze the behavior of complexation between the ligand and metal ion in aqueous solution. From these studies, the values of solvation and kinetic parameters [Ep (peak potential), Ip(peak current), ?EP (peak potential difference), E½ (half wave potential), D(Diffusion coefficient), Ks (electron transfer rate constant), ?(surface coverage) and Qa (quantity of electricity)] were evaluated. In addition, the effect of different concentration and a scan rate of above the calculated quantities were studied. In case of presence MB, the stability constants and Gibbs free energies were performed. |
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Ultrasensitive and selective non-enzymatic glucose detection based on pt electrode modified by carbon nanotubes@ graphene oxide/ nickel hydroxide-Nafion hybrid composite in alkaline media |
Author : Sirous Mohammadi; Alireza Taheri; Zeinab Rezayati-Zad |
Abstract | Full Text |
Abstract : Abstract A new enzymeless glucose sensor has been fabricated and its electrocatalytic oxidation has been investigated in alkaline medium directly on the Pt Electrode modified by Activated carbon nanotubes @ graphene oxide/ nickel hydroxide-Nafion hybrid composite (PtACNT@GONHNPsNf). Under the optimized condition, the calibration curve is linear in the concentration range of 5-1100 µM using cyclic voltammetric method. The detection limit and sensitivity are 0.75 µM and 40 nA, respectively. The glucose sensor can be renewed easily in a reproducible manner by a simple polishing step and it has a long operational lifetime and short response time t90% < 1 s. In addition, the fabrication of Pt with nafion and nickel hydroxide powder was employed to eliminate the interference of ascorbic acid during the catalytic oxidation of glucose. The biosensor was used for determination of glucose in human blood serum and the oxidant with satisfactory results. |
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Thermodynamic and Theoretical solvation parameters for 2-amino-4,5-dimethylthiophene-3-carboxamide(ADTC) in Ethanol and Mixed EtOH-H2O solvents |
Author : Essamhassan G Arafa Gomaa; Moged A. Berghout; Mohamed R. Moustafa; Fathy M. El Taweel; Hader M . Farid |
Abstract | Full Text |
Abstract :The molar solubility for 2-amino-4,5-dimethylthiophene-3-carboxamide (ADTC) in pure ethanol and mixed ethanol (EtOH)- water solvents were measured at five different temperatures, 293.15, 298.15, 303.15, 308.15, and 313.15 K in the used mixed solvents, the solubility were increase by increase in the mole fraction of ethanol in the mixtures and increase of temperature due to more salvation parameters. All the solvation and thermodynamic parameters for ADTC in mixed EtOH+ H2O solvents were evaluated like solubility products, Gibbs free energies, enthalpies and entropies of solvation and discussed. Theoretical calculations for (ADTC) were done quantum mechanically by using Gaussian on set of calculations in ethanol for evaluating the different thermodynamic parameters. |
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Antiulcerogenic Activity of methanol extract and solvent fractions of Stem Bark of Lannea acida (A. Rich) Against Ethanol-Induced Gastric Mucosal Injury in Albino Rats |
Author : Onoshe Solomon; Wasagu Rabiu Saidu Umar; Hassan Sanusi Wara; Abubakar Sadiq Yakubu; Madusolumou Michael Azubuike; Mbahi Asugu Mary; Hitler Louis |
Abstract | Full Text |
Abstract :Peptic ulcer disease is one of the most prevalent gastrointestinal disorders causing tremendous human suffering worldwide. The present study was designed to evaluate the antiulcerogenic activity of the methanol and solvent stem bark fractions (hexane, ethyl acetate and butanol) and elucidate their possible antiulcerogenic mechanisms. The antiulcerogenic mechanisms were investigated by estimation of Superoxide dismutase (SOD), Glutathione (GSH), Catalase (CAT), Vitamins A, C and E, Malondialdehyde (MDA) and involvement of KATP channel. Pretreatment with the methanol extract and solvent fractions produce significant reductions in ulcer index in a dose dependent manner. Ethylacetate fraction (EtyAc) showed the highest antiulcer activity. Elevated MDA and decreased levels of SOD, GSH, CAT, Vitamin A, C and E observed in ulcer control groups were significantly decreased and increased respectively in the EtyAc fraction treated groups. Antiulcer activity of the EtyAc fraction was blocked upon coadministration with glibenclamide; a KATP channel blocker. The stem bark extract of Lannea acida possess antiulcerogenic activity and the mechanisms seems to involve antioxidant activity and KATP channel opening. |
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Sorptive chelation of metals by inorganic functionalized organic WOx–EDA nanowires: adsorbent characterization and isotherm studies |
Author : Adams Udoji Itodo; Ohemu Michael Itodo; Esther Iornumbe; Michael Omotola Fayomi |
Abstract | Full Text |
Abstract :Synthesis and Characterization of Inorganic–organic hybrid Tungsten oxide-ethylenediamine (WOx–EDA) nanowires have been carried out by a simple, low-cost and high-yield solvo-thermal method. The WOx–EDA nanowire adsorbent was characterized using, Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Energy Dispersive X-ray spectroscopy (EDX). Adsorptive potential of the hybrid for aqueous phase copper and lead removal was investigated using batch adsorption process. The equilibrium data were subjected to various isotherm models. The Langmuir model shows high applicability (R2 of 0.921) for lead uptake. Other R2 values include 0.882 (for Freundlich model), 0.947 (Temkin) and 0.972 (Dubinin- Radushkevich). Similarly, adsorption experimental runs for Cu uptake gave correlation coefficient (R2) values of 0.972, 0.584, 0.906 and 0.899 for the Langmuir, Freundlich, Temkin and Dubinin- Radushkevich isotherm models respectively. Overall, Tungsten oxide ethylenediamine adsorbent proved its potential candidature for the chelating treatment of Pb and Cu poisoning as well as purifications of water containing such metals.
Sorptive chelation of metals by inorganic functionalized organic WOx–EDA nanowires: adsorbent characterization and isotherm studies |
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Reduced graphene oxide based on simultaneous detection of neurotransmitters |
Author : G. Vinodhkumar; R Ramya; mark vimalan; I Potheher; A. Cyrac Peter |
Abstract | Full Text |
Abstract : Abstract Reduced graphene oxide (rGO) is synthesized using strong oxidizing agents with the help of chemical reduction method. Structural and physiochemical properties of the prepared sample are studied by ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). UV-Vis spectra of GO exhibit maximum absorption peak attributable to restoration of sp2carbon. Electrochemical study performed for bare and rGO modified glassy carbon electrode. Electrochemical sensing of Dopamine (DA) and Uric Acid (UA) was examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) were conducted in phosphate buffer solution (PBS) at pH = 7.0 done for both simultaneous and individual determination of DA and UA in the range of 500nM – 1mM exhibit a wide linear range of detection and having low limit of detection (LOD) of 0.67µM for DA, and 0.69µM for UA estimated for simultaneous determination and in individual determination it was found to be 0.51µM and 0.42µM for DA and UA respectively. Additionally, the modified electrode exhibits good reproducibility, selectivity, sensitivity and stability. The proposed sensor could be applied for the determination of DA and UA in real samples. |
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Comparative study of pharmaceutical content of three different cardio vascular system drugs marketed in Tripoli- Libya |
Author : Amira Salem Zaek; Balsam Ali Benhamed; Mabroka Ali Al shahomy; Ruwida kamour; Akram Eshames |
Abstract | Full Text |
Abstract :Generic drugs have increased in their popularity as the cost of their brand counterparts have arisen. Post-marketing testing of some drugs is used to assure quality, efficacy and safety of those drugs made available for public use. This is to give evidence of their effectiveness.
This study was undertaken to justify the use of generic substitution of metoprolol, spironolactone and verapamil brands marketed in Tripoli-Libya. This evaluation was achieved through QC tests for hardness, disintegration time and chemical content according to British Pharmacopoeial standards. The results of these tests were found to comply with pharmacopoial range indicating their efficiency to be used as a substituent for brands of higher price. |
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Acute and subchronic toxicity profiles of Melastomastrum capitatum (Vahl) Fern. (Melastomataceae) root aqueous extract in Swiss albino mice |
Author : Cletus Anes Ukwubile; Emmanuel Oise Ikpefan; Mathias Simon Bingari; Livinus Tam |
Abstract | Full Text |
Abstract : Melastomastrum capitatum is a plant whose leaf extract is popularly known for its ability to cure cancer of the ovary in Mambila plateau towns in Nigeria. Apart from the leaves, the root extract has been used to manage various diseases such as bacterial infections, pains, and diabetes. As a result of these health benefits, liver and vital organ damage are often associated with short (acute) or long (subchronic) intake of this plant decoction in traditional medicines. This present study was carried out to determine short and long (subchronic) terms effect of the root aqueous extract for the treatment of diseases especially diabetes by the Fulani tribe in Mambila plateau in Taraba State, Nigeria. Acute and subchronic toxicity studies were carried out following the guidelines stipulated by the Organization for Economic Cooperation and Development (OECD). In the acute toxicity study, a limit test dose of 2000 mg/kg body weight (b.w) of aqueous root extract was administered by oral route into five Swiss albino mice consisting of five groups of one mouse per group. Observations were carefully made for signs of toxicity for the first 4 hours and then once daily for 2 weeks. A lower dose of 300 mg/kg b.w administered to the mice do not show any sign of acute toxicity unlike the higher dose which produced signs such a reddish eyes, itching and restlessness which last only a few minutes of extract administration. Subchronic toxicity study revealed that root extract of the plant is slightly toxic as had shown by results of most of blood parameters investigated such as WBC, PCV, ALT, AST, ALP, serum electrolytes, etc. However, our results showed that root aqueous extract of M. capitatum is well tolerated at the doses investigated as there was no major damage to vital organs like the liver, kidney and heart of the animals. The study therefore showed that the root extract of the plant is safe for use as an ethnomedicinal prescription for diseases in traditional medicine. |
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