Simultaneous assay of codeine phosphate and diphenhydramine hydrochloride in cough mixtures by zero-order derivative UV spectrophotometry
May 2011
This study evaluated a zero-order derivative UV spectrophotometric method for the simultaneous determination of binary components, codeine phosphate and diphenyhydramine HCl in cough mixtures. The method was based on the measurement of zero-order derivative amplitudes at isosbestic points, 258 and 264 nm, for the assay of codeine phosphate and diphenylhydramine HCl (0.05 to 0.15 mg/ml). The method does not...
Study on the properties of copolymer hydrogel obtained from acrylamide/2-hydroxyethyl methacrylate by the application of gamma radiation
May 2011
Synthesis of copolymer hydrogels from aqueous solution of acrylamide/2-hydroxyethyl methacrylate (HEMA) has been performed with radiation processing technology using Co-60 gamma source. The influence of radiation dose and concentration of HEMA on gel content, swelling properties and thermal stability of copolymer hydrogel has been investigated. Gel content of prepared hydrogel obtained maximum at the radiation dose of...
Antimicrobial effect of coastal medicinal plant – Citrullus colocynthis against pathogenic microorganisms
May 2011
Citrullus colocynthis showed broad spectrum antimicrobial activity against 16 clinical microorganisms isolated from HIV positive patients, including bacteria Viz., Bacillus subtilis, Escherichia coli, Klebseilla pneumoniae, Proteus mirabilis, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Streptococcus pyogenes, Salmonella typhi and Vibrio cholerae; and six fungal...
Chemical composition and biological activity of the volatile oils of Hyptis spicigera against Trypanosoma brucei brucei, (Tbb) found in Northern Nigeria
April 2011
The hydrodistillation of the fresh leaves of Hyptis spicigera gave a colourless volatile oil with yield of 0.65%.The volatile oil gave forty compounds on the basis of gas chromatography-mass spectroscopy (GC-MS) with low composition of cineole(4.11%) and caryophyllene (2.61%) while α-pinene (12.16%) β-pinene(9.47%) and α-phellandrene (10.19%) were predominant compounds. The...
Synthesis, characterization and trypanocidal activity of some aromatic thiosemicarbazones and their 1,3,4-thiadiazolines derivatives
April 2011
The thiosemicarbazones of six aromatic ketones were synthesized as well as their 1,3,4-thiadiazolines derivatives obtained by cyclization under acetylating condition with yields going from 40 to 90%. The products purity was confirmed by mass spectrometry coupled with high-performance liquid chromatography (LC/MS) and there were characterized using spectrometry IR, NMR 1H and 13C (nuclear magnetic...
Preliminary phytochemical and antimicrobial screening of the leaf extract of Cassia singueana Del
April 2011
Ethanolic and aqueous extracts of Cassia singueana Del. leaves were screened for their antimicrobial activity against Staphylococcus aureus, Streptococcus pyogen,Escherichia coli, Salmonella typii and Shigella dysentery. The result indicated that the extracts inhibited the growth of one or more test pathogens. The ethanolic extract showed a broad spectrum of...
Multiple regression analyses of kinetics of aquation reactions of some chromium (III) – alkyl amine complexes in mixed solvent media- A study of solvation mechanics
April 2011
Molecular dynamics of the aquation reactions of the complexes [Cr(en)2Cl2]Cl,[Cr(tn)2Cl2]Cl,[Cr(tetren)Cl]Cl2, [Cr(pn)2Cl2]Cl, [Cr(trien)Cl2]Cl and [Cr(dien)Cl3] have been extensively studied in mixed solvent media. Kinetics and thermodynamic parameters have been evaluated and the results are interpreted carefully in the light of statistical and regression models. Key words: Cr (III) complexes,...
Cytoprotective effect of Benzyl N'-(indol-3-ylmethylidene)-hydrazinecarbodithioate against ethanol-induced gastric mucosal injury in rats
March 2011
Benzyl N'-(indol-3-ylmethylidene)-hydrazinecarbodithioate (BIHC) and its metal complexes have been reported to have medicinal uses (Singh and Varshney, 2006). The present study was performed to evaluate, the acute toxicity and anti-ulcer activity of this BIHC against ethanol-induced gastric ulcer. Experimental animal groups were orally pre-treated with different doses of BIHC (50, 100, 200 and 400 mg/kg) in 10%...
Preliminary phytochemical and antimicrobial screening of the leaf extract Pilostigma reticulatum (dc) Hochst
March 2011
Ethanolic and aqueous extracts of Pilostigma reticulatum (dc) hochst were screened for their antimicrobial activity against Staphylococcus aureus, Streptococcus pyogen, Escherichia coli, Salmonella thypi and Shigella dysentery. The results indicated that the extracts inhibited the growth of one or more test pathogens. The ethanolic extract showed a broad spectrum of antimicrobial activity....
The magnetic properties of Co-Mo-S coatings by electrodeposition
March 2011
The nano-coated Co-s-Mo alloys were electrodeposited from electrolytic solutions containing CoSO4, Na2MoO4, ascorbic acid, thiourea, and hexamine. The coated Co-S-Mo alloys were obtained evolving to hard magnetic behaviour. The coatings characterised by metallic lustre. The surface morphology of the coating was investigated by scanning electron microscope (SEM). The many alloys were electrodeposited using these baths....
Synthesis, electronic spectra and inhibitory study of some Salicylaldehyde Schiff bases of 2-aminopyridine
February 2011
A series of Schiff bases namely N-(2-hydroxylbenzylidene)pyridin-2-amine (I), N-(5-nitro-2-hydroxylbenzylidene)pyridin-2-amine (II), N-(5-bromo-2-hydroxylbenzylidene)pyridin-2-amine (III) and N-(5-methoxy-2-hydroxylbenzylidene)pyridin-2-amine (IV) derived from 2-aminopyridine and substituted benzyaldehydes are reported and characterized by IR, 1HNMR and elemental analysis. The...
Organotin dithiobiurets as corrosion inhibitors for mild steel-dimethyl sulfoxide containing HCl
February 2011
Corrosion inhibition studies of mild steel in dimethyl sulfoxide containing HCl have been performed at 25°C using dithiobiurets and their triphenyltin- and dibutyltin complexes as inhibitors. The inhibition efficiency (IE) of these compounds was evaluated by electrochemical polarization technique. Among the ligands, best performance was exhibited by ethoxyphenyl derivative. The IE values of the ligands enhanced...
Characterization of caffeine and determination of caffeine in tea leaves using uv-visible spectrometer
January 2011
In this research, characterization of pure caffeine and the method for determination of caffeine content in twelve commercial tea leaves have been reported using UV-visible spectrometer. The optical transition properties of caffeine were measured in different solvents (dichloromethane, water, chloroform and ethyl acetate). The results show that, caffeine has highest optical transitions in dichloromethane than the other...
Synthesis of 4-(2-Indenylethyl)morpholine and their cationic transition metal complexes
January 2011
The amido tethered ligand 4–(2–indenylethyl)morpholine (6) have been prepared in high yield (71%). All the compounds were fully characterized by NMR, IR, Mass Spec. and Microanalysis. Treatment of the lithio salt of (6) with TiCl4:2THF in THF afforded the new complex 4–(2–indenylethyl)morpholinetitanium dichloride (7a) in 26% yield as viscous green oil while, treatment with ZrCl22THF gave...
Kinetic approach to the mechanism of the redox reaction of malachite green and permanganate ion in aqueous acidic medium
December 2010
The redox kinetic and mechanistic studies of the reactions of malachite green (MG+) and MnO4– were carried out in aqueous acidic medium, at a temperature of 32.5 ± 0.5°C; ionic strength, m = 0.50 mol dm–3 (Na2SO4), [H+] = 5.00 x 10–3 mol dm–3 (H2SO4). In the stoichiometry, one mole of malachite green was consumed by one mole of MnO4–. The...
The potential of secondary metabolites in plant material as deterents against insect pests: A review
December 2010
The potential of using plant material as deterrent against pest in crops, on the field and during post-harvest period, is a study that is presently gaining acceptance as a result of the indiscriminate use of chemical pesticides which has given rise to many well-known problems, including genetic resistance of pest species, toxic residues in stored products, increasing costs of application, hazards from handling and...
An efficient synthesis and DNA binding interaction study of some novel heterocyclic fused-pyarzolequinolines: A potent antimicrobial agent
December 2010
In the present paper, the synthesis of 3-(5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)quinolin-2-ol (2a)/(3a) and 3-(2-hydroxyquinolin-3-yl)-5-phenyl-4,5-dihydro-1H-pyrazole-1 carbothioamide(4a) were prepared according to Claisen-Schmidt condensation, viacondensation of 2- hydroxyquinoline-3-carbaldehyde with ketones. Then finally, α, β-unsaturated ketone (3) reacts with hydrazine hydrate,...
Studies on some diazo coupled products of chromium(III) chelates of acetylacetone and benzoylacetone
November 2010
A number of diazo coupled products of chromium(III) chelates of acetylacetone and benzoylacetone were prepared by using some aryl diazonium ions. The aryl diazonium ions of 4-chloro, 4-bromo, 2,5-dimethoxy, 4-nitro and 1-naphthyl were synthesized by diazotization of respective aniline groups. The prepared diazo coupled products were characterized on the basis of their analytical data, magnetic moment, 1H NMR...
Evaluation of Lead, Cadmium and Chromium in Tilapia fish obtained from Makoko and Carter Bridge Rivers in Lagos, Nigeria
November 2010
Most of the fresh water fish consumed in Nigeria comes from the Southern part of the country. The major aim of this study was to evaluate the heavy metal concentrations of Tilapia fish (Tilapia orechromis) of Makoko and Carter Bridge Rivers, thereby conducting a health risk assessment of these fishes. Heavy metal analyses were carried out by atomic absorption spectrophotometry (AAS). Lead concentrations...
Synthesis of novel 2-quinolone derivatives
November 2010
In this work, N-amino quinoline-2-one (2) has been synthesized by the reflux of coumarin (1) with hydrazine hydrate (99%) in ethanol for 12 h. The azomethines (3-6) were prepared from the corresponding aryl aldehydes and ketones. Tetrazine derivative (7) was prepared from the reaction of compound (2) with CS2 and hydrazine hydrate in the presence of potassium hydroxide. However, the reaction of compound (2) with thiol...
Characterization of colour from some dye-yielding plants in Uganda
November 2010
Dyes from nine selected dye-yielding plants namely Albizia coriaria (bark), Vitellaria paradoxa (bark), Curcuma longa Linn (roots), Indigofera arrecta (leaves), Syzygium cordatum (bark), Morinda lucida (bark), Morinda lucida (roots), Rubia cordifolia (roots),Mangifera indica (bark) and Justicia betonica (leaves), collected from...
Phytochemical studies and pharmacological investigations on the flowers of Acacia arabica
November 2010
Fresh flowers of Acacia arabica willd were extracted with 80% alcohol and the concentrated extract was fractionated in the usual way. The ethyl acetate fraction was found to contain isoquercetin. The structure was characterized by UV, NMR, Paper Chromatographic and Chemical studies. The yellow pigment was found to contain promising results with respect to acute and chronic anti-inflammatory studies. It also...
The ground state structure and properties of erythritol in gas phase and in different solvents: A DFT / SC-IPCM approach
October 2010
Quantum mechanical study of the ground state structure and properties of erythritol was carried out in gas phase and in different solvents at the hybrid B3LYP DFT level with complete geometry optimization and varying basis sets [6-311G (d,p) and 6-311++G (d,p)] in order to provide detailed information of the model molecule in solvents of low, medium and high dielectric constant. It was found that the molecule is...
Synthesis and characterization of a novel ionic liquid (TBA-AMPS) and its applications in Mannich condensation reactions under solvent free conditions
October 2010
This paper deals with the synthesis and characterization of a novel ionic liquid using green chemicals such as tetra-butyl ammonium chloride (TBA) and 2-acrylamido-2-methylpropanesulphonate (AMPS) via an anion metathesis reaction and characterization by 1H-NMR technique. Also, this ionic liquid was used to catalyze Mannich reactions under solvent free conditions to afford the corresponding β- amino...
Solvent effects and photophysical studies of ADS560EI laser dye
October 2010
The ground state (μg) and the excited state (μe) dipole moments of a laser dye ADS560EI is estimated in various solvents by Lippert, Backshieve, Kawski-Chamma-Viallet, McRae and Suppan equations using the variation of stokes shift with the solvent dielectric constant and refractive index. The excited state dipole moments were also calculated by using the variation of stokes shift with microscopic solvent polarity...
Natural rubber/organoclay nanocomposites: Effect of filler dosage on the physicomechanical properties of vulcanizates
October 2010
Natural rubber/organoclay nanocomposites of varying filler loading [2 to 10 per hundred rubber (phr)] using derivative of tea (Camellia sinensis) seed oil were prepared by melt intercalation. Effects of filler dosage on the physicomechanical properties of the natural rubber (NR) vulcanizates were examined. Results of the mechanical properties indicates that tensile strength and tear properties of the modified...
Comparative phytochemical and antimicrobial screening of some solvent extracts of Samanea saman (fabaceae or mimosaceae) pods
October 2010
Antimicrobial activity of distilled water (DE), methanol (ME), ethanol (EE) and ethyl acetate (EAE) extracts of Samanea saman pods was investigated by well-diffusion method against five pathogenic organisms: Bacillus subtilis (B. subtilis), Staphylococsus aureus (S. aureus), Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Candida albicans (C. albicans). Only ME showed measurable...
Antioxidants: Its medicinal and pharmacological applications
August 2010
Antioxidants are essential and important for plants and animals’ sustenance. They are substances that protect cells from the damage caused by unstable molecules known as free radicals. The sources and origin of antioxidants which include fruits and vegetables, meats, poultry and fish were treated in this study. The types of antioxidants such as Ascorbic acid, glutathione, melatonin, tocopherols and tocotrienols...
Synthesis of polymethyl methacrylate (PMMA) by batch emulsion polymerization
August 2010
Poly (methyl methacrylate) was synthesized by batch emulsion polymerization with Methyl Methacrylate as the monomer potassium peroxo-disulfate as the initiator, sodium stearate as the emulsifier and distilled water as a medium. The kinetics of free radical polymerization was studied. The kinetics has been modeled, assuming homogeneous nucleation and the resulting equation were solved using Runge-kutta method. Degree of...
The inhibitive effect of Solanum melongena L. leaf extract on the corrosion of aluminium in tetraoxosulphate (VI) acid
August 2010
The effect of Solanum melongena L. leaf extract on the corrosion of aluminium in 0.5 M H2SO4 was investigated by using the gravimetric technique. It was shown that the presence of S. melongena L. leaf extract inhibited the corrosion of aluminium in the test solutions and that the inhibition efficiency depended on the concentration of the plant extract as well as on the time of exposure of the...
Remediation of arsenic from water/waste water using engineered carbon (EC)
August 2010
In the arena of eco-toxicological world, Arsenic pollution is a matter of alarming concern. Intake of arsenic contaminated water having concentration above the permissible limit causes Arsenic poisoning in living beings. In the present study, a batch mode lab. experiment was done using adsorption technology. Here, engineered carbon (EC) was used for remediation of arsenic from water/waste water. A significant amount of...
1H and 31P–NMR monitored cross-metathesis reaction of octavinylsilsesquioxane hybrid nanocomposite with ruthenium carbene: Possibility for multifunctional octasilsesquioxane derivatives
August 2010
Cross metathesis reaction of octavinylsilsesquioxane 1 with Grubb’s carbene 2 in CDCl3 has been monitored by 1H – and 31P – NMR spectroscopy. Reaction in the presence of excess 1 afforded a ruthenium alkylidene resonance attributable to a monofunctional derivative of 1, while in the presence of excess 2, a tetrafunctional derivative resulted as determined by 1H - ,31P – NMR...
Kinetics of thermal substitution reactions of some Chromium (III) -alkyl amine complexes in mixed solvent media
July 2010
Molecular dynamics of the aquation reactions of the complexes [Cr(en)2Cl2]Cl, [Cr(tn)2Cl2]Cl, [Cr(tetren)Cl]Cl2, [Cr(pn)2Cl2]Cl, [Cr(trien)Cl2]Cl and [Cr(dien)Cl3] have been extensively studied in mixed solvent media. Kinetics and thermodynamic parameters have been evaluated and the results are interpreted carefully in the light of statistical and regression models. Key words: Cr (III) complexes,...
Gas chromatography – mass spectrometry analysis of the hexane extract of Calliandra portoricensis and its antimicrobial activity
July 2010
Calliandra portoriscensis is widely used in traditional medicine preparation in South western part of Nigeria for the management of sickle cell crisis and other health challenges. Analysis of the hexane extract of C. portoricensis by GC-MS revealed 14 – methyl methylpentadecanoate as the major component. Other fatty acids/fatty acid methyl esters detected were hexadecanoic acid,...
SEM Characterization of the mass transfer of Cr(VI) during the adsorption on used black tea leaves
July 2010
This study presents the mass transfer mechanism of Cr(VI) during the adsorption on used black tea leaves (UBTLs) as a low cost biosorbent. Batch adsorption experiments were conducted in acidic media with different particle sizes of UBTLs and Cr(VI) concentrations, and the results were verified with different transport models to elucidate the mass transfer mechanism. Scanning electron microscope (SEM) and X-ray...
Design, synthesis and bioassay of novel coumarins
June 2010
In Iraq like most third world countries, attempts to discover new antibiotic drugs derived from coumarins moreover develop the branch of applied in organic chemistry. Novel coumarin derivatives were synthesized in a good yield through converting lacton to lactam and study the biological activity of the synthesized compounds. Coumarins were characterized by elemental analysis, FT-IR, 1H-NMR and UV/visible spectra....
Surface modification with copper by electroless deposition technique: An overview
June 2010
Surface behaviour is very important for which substrate surface preparation is emphasized in electroless deposition process. It directly or indirectly affects surface behaviour as well as the kinetics of electroless deposition process. So far as mechanism is concerned, it proceeds in an electrochemical pathway. The electrochemical approach provides clarity of the mechanism by studying independently the partial anodic...
Applicability of an ionic liquid in the removal of chromium from tannery effluents: A green chemical approach
June 2010
The task specific ionic liquid tricaprylmethyl ammonium thiosalicylate proved to be an excellent extraction agent for chromium from aqueous solution. Chromium was removed from tannery effluents to a greater extent than the conventional methods; using the water insoluble, thiol containing task specific ionic liquid. Key words: Task- specific...
Palladium (II)-triphenylphosphine-arylazoimidazole complexes: Synthesis and spectroscopic characterization
June 2010
Reaction of [Pd(PPh3)2Cl2/Br2] with AgOTf in dichloromethane followed by addition of ligand leads to [Pd(PPh3)2(OSO2CF3)2] and then [Pd(PPh3)2(RaaiR)](OSO2CF3)2 [RaaiR/ = p-R-C6H4-N=N-C3H2-NN-1-R/, (1-3), abbreviated as N,N/-chelator, where N(imidazole) and N(azo) represent N and N/, respectively; R = H (a), Me (b), Cl (c) and R/ = Me (1), CH2CH3 (2), CH2Ph (3), OSO2CF3 is the triflate anion]. 31P...
Synthesis of nano-nickel by a wet chemical reduction method in the presence of surfactant (SDS) and a polymer (PVP)
May 2010
Nano-sized nickel particles have been synthesized by a bottom-up approach, using hydrazine as the reducing agent in the presence of an anionic surfactant - sodium-dodecyl sulphate (SDS). The effect of adding a cationic polymer -polyvinylpyrrolidone (PVP) with an anionic surfactant has been studied at two different temperatures; the rate of reduction increased as the reaction temperature was increased from 60 to...
Kinetics study of fibrinogen adsorbed on titanium powder
May 2010
A kinetics study of fibrinogen adsorbed on titanium has been investigated by means of spectrophotometer of the type developed for micro-enzyme linked immune-sorbent assay determination. Implants invoke inflammatory responses from the body and an attempt to alleviate the problem caused by the adsorption of protein on artificial implants mostly used in the medical, informed this study. The experimental isotherm data were...
A study on the anticancer activities of ethanolic curcumin extract
May 2010
In Iraq like most third world countries, attempts to extract, identify and study the anticancer activity of the active components of plants and use it as drugs. Curcumin[(1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5dione] is the major yellow pigment extracted from turmeric, a commonly used spice, derived from the rhizome of the plant Curcuma longa. In India and Southeast Asia, turmeric has long been...
Redox and spectral behaviour of copper (II)-chloro and bromo complexes in some nonaqueous solvents
April 2010
The redox behaviour of 3 × 10-3 M each of CuCl2.2H2O and CuBr2.H20 have been investigated at Platinum (Pt) electrode and 1 × 10-3 M CuCl2.2H20 at glassy carbon (GCE) electrode in dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetonitrile (AN) and ethanol/0.1 M tetrabutylammonium perchlorate (TBAP) using cyclic voltammetry. For CuCl2 System, Epc1 and E0 are more positive, ∆Ep...
Biotransformation of n – phenyl cyclohexenylimide and 3, 5 – dinitrobenzoic acid
April 2010
N - phenyl cyclohexenylimide and 3,5 - dinitrobenzoic acid were subjected to biotransformation on maize fermenting system. These compounds were left for two weeks in the fermenting system and later extracted with a mixture of n - hexane, diethyl ether and ethanol. The TLC of the biotransformed products were carried out. The structures proposed for the isolated biotransformed products were based on FT - IR and NMR...
Dynamical behavior of coumarin compounds in alcohol solvents
April 2010
Dynamical behavior of 3-(2-Benzimidazolyl)-7-(DiethylAmino) coumarin [coumarin7 (C7)] and 3-(2-N-Methylbenzimidazolyl)-7-N, N-diethylamino coumarin [coumarin30 (C30)] laser dyes have been examined in methanol as a function of temperature. It is observed that, the rotational motion of probe molecule in methanol solvent increases as the temperature increase. We also investigated that, C30 rotates faster than C7 in the...
Analysis of heavy metals concentration in road sides soil in Yauri, Nigeria
March 2010
Assessment of seasonal variation in physiochemical properties and concentration of the heavy metals in road side soil in Yauri, was undertaking during the two major seasons of Nigeria. This was done to determine the environmental pollution status of the soil at the road side. Soil samples collected during the 2007/2008 rainy and dry seasons were treated and digested using microwave acid digestion methods. The heavy...
A study of the biological activities of Avena sativa extracts
March 2010
In Iraq like most third world countries, attempts to extract, identify and study the activity of the active components of plants and use it as drugs. The use of herbal medicine predates the introduction of antibiotics and predates social, economic and religious barriers. The extract of the herb Avena sativa L. (Gramineae), from Iraq, was done by using of 70% ethanol as a solvent, the study the antimicrobial...
Chemical composition and cytotoxicity of the essential oils of Crinum ornatum (Ait.) Bury
March 2010
The bulbs of Crinum ornatum were collected, dried and grounded. The powdered samples were subjected to distillation using a hydro-distiller (all-glass clevenger apparatus) to extract the essential oil present in the plant samples. GC and GC/MS analysis were carried out on the essential oil and was found to contain 18 compounds; hydrocarbons being the dominating group of compounds. They are...
Inhibition effects of some plant extracts on the acid corrosion of aluminium alloy
February 2010
Corrosion inhibition of aluminium alloy (AA3003) in 0.5 M HCl by extracts of selected plants was investigated using gravimetric technique at 30 and 60°C. The studied plant materials include extracts of Euphorbia hirta and Dialum guineense. The results indicate that all the extracts inhibited the corrosion process in the medium by virtue of adsorption and inhibition efficiency improved...
Determination of heavy metal pollutants in street dust of Yola, Adamawa State, Nigeria
February 2010
Contamination of the environment by heavy metals is a phenomenon of global importance today. When present in high concentrations in the environment, heavy metals may enter the food chain from soils and result in health hazards. This study is aimed at determining the elemental concentrations of heavy metal pollutants that may be present in street dust samples in Yola, Adamawa State, Nigeria. Dust samples...
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