Phytochemical screening and determination of flavonoids in Secamone afzelii (Asclepiadaceae) extracts
August 2008
The goal of this survey is to determine the amount of flavonoids in the leaves and stems of Secamone afzelii (Asclepiadaceae), a plant possessing some antioxidants qualities. The phytochemical screening revealed that the flavonoids are more abundant in the leaves than in the stems. The amount of anthocyane is 336 mg/100 g in the leaves, whereas it is only of 180 mg/100 g in the stems. We also discovered that...
The study of reactivity and selectivity of tertiary amines with aryl chlorothionoformates
July 2008
o-Nitrophenyl chlorothionoformate reacts readily with unhindered tertiary aliphatic amines in only 10 min at room temperature, and gives the dialkylamine salts after treatment of initial thiocarbamate with dimethyl sulfate followed by hydrolysis with water. The ease of cleavage of alkyl groups from tertiary amines with 4-chlorophenyl chlorothionoformate is benzyl > t-butyl > allyl > methyl and using 2, 4,...
Synthesis, characterization, antimicrobial activity and toxicology study of some metal complexes of mixed antibiotics
July 2008
Mixed ligand metal complexes of ampicillin and chloramphenicol prepared by using Ni(II), Co(II) and Fe(III) metal chloride hexahydrate were reported and characterized based on some physical properties and spectroscopic analysis such as AAS, UV, and IR spectroscopy. The complexes were proposed to have the formulae [ML1L2](Cl)n ( where M= Ni(II), Co(II), Fe(III); L1 =ampicillin, L2 = chloramphenicol , and...
Adsorption and inhibitive properties of ethanol extracts of Musa sapientum peels as a green corrosion inhibitor for mild steel in H2SO4
June 2008
The inhibition of the corrosion of mild steel by ethanol extract of Musa sapientumpeels in H2SO4 has been studied using gasometric and thermometric methods. The results of the study reveals that the different concentrations of ethanol extract of M. sapientum peels inhibit mild steel corrosion. Inhibition efficiency of the extract is found to vary with concentration, temperature, period of...
Oxovanadium (IV) esters of ciprofloxacin: Their characterization and potentiometric study
June 2008
The reaction between ciprofloxacin and VOSO4.3H2O in 1:1, 1:2 and 1:3 molar ratio in methanol was investigated at 20ËšC, 0ËšC and -10ËšC. In various pH conditions the different complexes which are formulated as VO(H2O)3L, VO(H2O)L2 and VL3 have been formed by titration of VOSO4.3H2O with ciprofloxacin in the presence of NaOH. These complexes have been characterized by IR spectroscopy. The order of...
Physico-chemical analysis and toxicological studies of Madaran sukudai (a local drink in Northern Nigeria)
June 2008
Physico-chemical analyses have been carried out on concentrated Madaran sukudai, diluted M. sukudai and pure formalin. Both the infrared and UV-visible spectroscopic studies on the three solutions revealed that the madaran sukudai is essentially a dilute formalin solution. Toxicological studies of the effect of M. sukudai on the white albino rats were also carried out. The results showed that there was significant...
Effect of intraperitoneal administration of vitamin C (ascorbic acid) on anemia in experimental Trypanosoma congolense infected rabbits
April 2008
The effect of Vitamin C supplementation on anemia in experimental Trypanosoma congolense infected rabbits was investigated. Locally bred rabbits were infected with 6 ´ 106 trypanosomes per rabbit and infection was monitored for 5 weeks. Packed cell volume (PCV), Total leucocytes count (TLC) and parasite load were determined weekly. Vitamin C supplementation did not significantly affect...
Miscibility studies of PVC/PMMA and PS/PMMA blends by dilute solution viscometry and FTIR
April 2008
The effect of polymer-polymer interactions on the miscibility of PVC/PMMA and PS/PMMA blends were studied in a broad composition range using viscosity and FTIR techniques. From the viscometric data, the presence of attractive forces among different polymers was evaluated according to Sun et al. (1990), by the determination of α ï€ parameter. Based on sign convention involved in the criterion, PS/PMMA system was...
Nanotechnology importance in the pharmaceutical industry
March 2008
During the last decades, pharmaceutical technology has taken the advantage of the advent of nanotechnology and, now days, new pharmaceutical dosage forms are under development to deliver many physicochemically different drug molecules. The present study is to investigate the role and their importance of nanotechnology in the pharmaceutical development. Key words: Nanotechnology, drug delivery,...
Application of grafted membranes for sorption of Cd2+, Fe2+ and Zn2+ ions in aqueous solution
March 2008
Sorption of Cd2+, Fe2+ and Zn2+ by blend membrane of sodium alginate (Na-Alg) and poly (acrylamide) grafted konkoli gum (KG-g-PAAM) in aqueous solution was studied. Membrane sorption capacities for Cd2+, Fe2+ and Zn2+were found to be 97.85, 80.65 and 64.46% respectively. The sorption behavior with respect to contact time, initial pH, temperature, ionic strength and initial metal ion...
Development and validation of LC method for the determination of leflunomide in pharmaceutical formulations using an experimental design
February 2008
A rapid and sensitive RP-HPLC method with UV detection (260 nm) for routine analysis of leflunomide in a pharmaceutical formulation was developed. Chromatography was performed with mobile phase containing a mixture of acetonitrile and phosphate buffer (60:40, v/v) with flow rate of 0.8 ml min−1. Quantitation was accomplished with internal standard method. The procedure was validated for linearity...
Enhancing trends of intensity signal of trace level Hf in zirconium oxide using AES sequential addition method
February 2008
A sensitive, rapid and simple method to detect Hf at trace level in Zr has been described. It is based on the sequential addition of sample after each pre excitation period, in presence of graphite as buffer. The improvement with respect to the other published procedures lies in the use of solid powdered sample, omitting the step of wet chemistry or use of any optical filter. The enhancing trends of intensity curves...
Chromatographic method development: computer simulated statistical design approach
January 2008
The computerization of method development and validation are useful in analysis of pharmaceuticals in pharmaceutical industry. In this article a simple and rapid high performance liquid chromatographic method has been developed for the determination of oxcarbazipine in pharmaceutical formulations. Factorial design was applied for optimization of essential factors for robustness study. A linear model was postulated and a...
Study on QSPR method for theoretical calculation of heat of formation for some organic compounds
January 2008
Quantitative Structure – Property Relationship (QSPR) models based on molecular descriptors derived from molecular structures have been used for the prediction of heat of formation using a set of 20 organic compounds. The molecular and quantum chemical descriptors used to represent molecular structure include topological indices and constitutional descriptors. Forward stepwise regression was used to...
Contribution from the employment of volcanic tuffs to the chemistry of soda- lime glasses
November 2007
The present work shows a study to incorporate volcanic tuffs as raw material in the preparation of industrial glass that traditionally uses feldspar. The X- ray diffraction patterns obtained with hot camera depict an unstable mineralogical phase under special conditions of atmospheric pressure in which appears the quartz polymorphic transformation. Thermal analysis curves present a shoulder at 680oC and an endothermic...
Chemical oxides analysis from Azara Baryte
November 2007
Physical and chemical analysis of the two samples A and B of Azara baryte were conducted, such as moisture content, loss on ignition and elemental composition by the use of atomic absorption spectrophotometer(ASS) and flame photometer. The oxides values in 1.000 g sample of each element were obtained. Sample A (lower layer): moisture content = 0.020, loss on ignition = 0.060, Na2O = 0.250, K2O = 0.015, CaO = 0.014, MgO...
omputational approach of protein analysis using affinity chromatography: application to proteomics
September 2007
Computerization is necessary to build the database of chromatography coupled mass spectrometric analytical data. On the basis of this proteomic data we can identify the proteins as biomarkers which are expressing dissimilarity between healthy and disease condition. Affinity chromatography is one of the fastest liquid chromato-graphic methods for the separation and purification of biomolecules due to its high molecular...
Tetrapropylammonium bromochromate and tetrabutylammonium bromochromate [NR4]CrO3Br, (R= Pr, Bu): two new and efficient reagents for oxidation of alcohols
September 2007
Tetrapropylammonium bromochromate (VI), [N(Pr)4]CrO3Br, TPABC and tetrabutyl-ammonium bromochromate (VI), [N(Bu)4]CrO3Br, TBABC were prepared and used to quantitatively oxidizing of a number of organic substrates. These reagents are versatile reagents for the effective and selective oxidation of organic substrates, in particular for alcohols, under mild conditions. Key...
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