Effect of substitution of blast-furnace slag by fired drinking water sludge on the properties of pozzolanic cement pastes

Journal of Thermal Analysis and Calorimetry - The effect of fired drinking water sludge (FDWS) as a mineral admixture on the physico-mechanical properties and the fire resistance of pozzolanic...     

Spectroscopic, structure and antimicrobial activity of new Y(III) and Zr(IV) ciprofloxacin

The preparation and characterization of the new solid complexes [Y(CIP)2(H2O)2]Cl(3)·10H2O and [ZrO(CIP)2Cl]Cl·15H2O formed in the reaction of ciprofloxacin (CIP) with YCl3 and ZrOCl(2)·8H2O in ethanol and methanol, respectively, at room temperature were reported. The isolated complexes have been characterized with elemental analysis, IR spectroscopy, conductance measurements, UV-vis and 1H NMR spectroscopic methods and thermal analyses. The results support the formation of the complexes and indicate that ciprofloxacin reacts as a bidentate ligand bound to the metal ion through the pyridone oxygen and one carboxylato oxygen. The activation energies, E*; entropies, ΔS*; enthalpies, ΔH*; Gibbs free energies, ΔG*, of the thermal decomposition reactions have been derived from thermogravimetric (TGA) and differential thermogravimetric (DTG) curves, using Coats-Redfern and Horowitz-Metzeger methods. The proposed structure of the two complexes was detected by using the density functional theory (DFT) at the B3LYP/CEP-31G level of theory. The ligand as well as their metal complexes was also evaluated for their antibacterial activity against several bacterial species, such as Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) and antifungal screening was studied against two species (Penicillium (P. rotatum) and Trichoderma (T. sp.)). This study showed that the metal complexes are more antibacterial as compared to free ligand and no antifungal activity observed for ligand and their complexes.     

Preparation and Spectroscopic of Vanadyl(Ⅱ) Vitamin D_3 Amino Acid Mixed Complexes as Insulin Mimetic Drug

A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD-1₃)(VO+2)(AA-1_n)] (where (n=1～6); AA₁=isoleucine, AA₂=threonine, AA₃=proline, AA₄=phenylalanine, AA₅=lysine and AA₆=glutamine) were synthesized by the chemical reactions between vitamin D₃ (VD₃), VOSO₄ and amino acids (AA_n) with equal molar ratio 1∶1∶1 in neutralized media. The structures of these complexes were elucidated by spectroscopic methods like, infrared and solid reflectance spectroscopes. Magnetic moments and electronic spectra reveal square pyramid geometrical structure of the complexes. The infrared spectra assignments of these complexes revealed that the chelation towards vanadyl(Ⅳ) ions existed via deprotonation of the hydroxyl group of VD₃ drug ligand and so amino acids act as bidentate ligand via N-amino and O-carboxylate groups. The anti-diabetic efficiency of these complexes were evaluated against streptozotocin induced diabetic male albino rats.     

Physico-chemical and Thermal Characteristics of Lime-silica Fume Pastes

Five lime-silica fume pastes were investigated using initial CaO/SiO₂ molar ratios of 0.80, 1.0, 1.30, 1.70 and 2.0. The kinetics and mechanism of hydration interaction between lime and silica fume were studied on the basis of the phase composition and the physical state of the formed hydration products. The developed strength could be related to the lime content of the lime-silica mixture and the formed hydrates. This revised version was published online in August 2006 with corrections to the Cover Date.     

Utilization of oxidation reactions for the spectrophotometric determination of captopril using brominating agents

Three simple, accurate and sensitive methods (A–C) for the spectrophotometric assay of captopril (CPL) in bulk drug, in dosage forms and in the presence of its oxidative degradates have been described. The methods are based on the bromination of captopril with a solution of excess brominating mixture in hydrochloric acid medium. After bromination, the excess brominating mixture is followed by the estimation of surplus bromine by three different reaction schemes. In the first method (A), the determination of the residual bromine is based on its ability to bleach the indigo carmine dye and measuring the absorbance at 610 nm. Method B, involves treating the unreacted bromine with a measured excess of iron(II) and the remaining iron(II) is complexed with 1,10-phenanthroline and the increase in absorbance is measured at 510 nm. In method (C), the surplus bromine is treated with excess of iron(II) and the resulting iron(III) is complexed with thiocyanate and the absorbance is measured at 478 nm. In all the methods, the amount of bromine reacted corresponds to the drug content. The different experimental parameters affecting the development and stability of the color are carefully studied and optimized. Beer's law is valid within a concentration range of 0.4–6.0, 0.4–2.8 and 1.2–4.8 μg mL^?1 for methods A, B and C, respectively. The calculated apparent molar absorptivity was found to be 5.16 × 10⁴, 9.95 × 10⁴ and 1.74 × 10⁵ L mol^?1 cm^?1, for methods A, B and C, respectively. Sandell's sensitivity, correlation coefficients, detection and quantification limits are also reported. No interference was observed from common additives found in pharmaceutical preparations. The proposed methods are successfully applied to the determination of CPL in the tablet formulations with mean recoveries of 99.94–100.11% and the results were statistically compared with those of a reference method by applying Student's t- and F-test.     

Indirect spectrophotometric determination of gentamicin and vancomycin antibiotics based on their oxidation by potassium permanganate

Four simple, accurate, sensitive and economical procedures (A–D) for the estimation of gentamicin sulphate and vancomycin hydrochloride, both in pure form and in pharmaceutical formulations have been developed. The methods are based on the oxidation of the studied drugs by a known excess of potassium permanganate in sulphuric acid medium and subsequent determination of unreacted oxidant by reacting it with amaranth dye (method A), acid orange II (method B), indigocarmine (method C) and methylene blue (method D), in the same acid medium at a suitable λ_max=521, 485, 610 and 664 nm, respectively. The reacted oxidant corresponds to the drug content. Regression analysis of Beer-Lambert plots showed good correlations in the concentration ranges 4–8, 3–8, 4–9 and 5–9 μg ml⁻¹ with gentamicin and 4–8, 1.5–4, 1.5–4 and 3.5–5.5 μg ml⁻¹ with vancomycin for methods A, B, C, and D, respectively. The molar absorptivity, sandell sensitivity, detection and quantification limits were calculated. The stoichiometric ratios for the cited drugs were studied. The optimum reaction conditions and other analytical parameters were evaluated. The influence of the substance commonly employed as excipients with these drugs were studied. The proposed methods were applied to the determination of these drugs in pharmaceutical formulations. The results have demonstrated that the methods are equally accurate and reproducible as the official methods.     

The Healing Capability of Clove Flower Extract (CFE) in Streptozotocin-Induced (STZ-Induced) Diabetic Rat Wounds Infected with Multidrug Resistant Bacteria

Treatment of diabetic foot ulcer (DFU) is of great challenge as it is shown to be infected by multidrug resistant bacteria (MDR bacteria). Sixty four bacterial isolates were isolated from DFU cases; antibiotic susceptibility tests were carried out for all of them. One bacterial isolate (number 11) was shown to resist the action of 8 out of 12 antibiotics used and was identified by both a Vitek-2 system and 16S rRNA fingerprints as belonging to Proteus mirabilis, and was designated Proteus mirabilis {"type":"entrez-nucleotide","attrs":{"text":"LC587231","term_id":"1917123988"}}LC587231 (P. mirabilis). Clove flower extract (CFE) inhibited distinctively the P. mirabilis bacterium obtained. GC-MS spectroscopy showed that this CFE contained nine bioactive compounds. The effect of CFE on wound healing of Type 1 diabetic albino rats (Rattus norvegicus) was studied. The results indicated that topical application of CFE hydrogel improved wound size, wound index, mRNA expression of the wound healing markers (Coli1, MMP9, Fibronectin, PCNA, and TGFβ), growth factor signaling pathways (PPAR-α, PGC1-α, GLP-1, GLPr-1, EGF-β, EGF-βr, VEGF-β, and FGF-β), inflammatory cytokine expression (IL8, TNFα, NFKβ, IL1β, and MCP1), as well as anti-inflammatory cytokines (IL4 & IL10), pro-apoptotic markers (FAS, FAS-L, BAX, BAX/BCL-2, Caspase-3, P53, P38), as well as an antiapoptotic one (BCL2). Furthermore, it improved the wound oxidative state and reduced the wound microbial load, as the cefepime therapy improved the wound healing parameters. Based on the previous notions, it could be concluded that CFE represents a valid antibiotics alternative for DFU therapy since it improves diabetic wound healing and exerts antibacterial activity either in vitro or in vivo.     

UV-vis, IR spectra and thermal studies of charge transfer complex formed between poly(amidoamine) dendrimers and iodine

The intermolecular charge-transfer (CT) complexes formed between two poly(amidoamine) dendrimers (PAMAM) from zero (D1) and second generation (D2) as donor and iodine as sigma-acceptor have been studied spectrophotometrically in the chloroform medium. The suggested structures of the solid iodine charge-transfer complexes investigated by several techniques using elemental analysis, mid infrared spectra, and thermal analysis (TGA and DTG) of the solid CT-complexes along with the photometric titration curves for the reactions. The results indicate the formation of two CT-complexes [(D1)]-I(2) and [(D2)]-2I(2) with acceptor:donor molar ratios of 1:1 and 1:2, respectively. The kinetic parameters (non-isothermal method) for their decomposition have been evaluated by graphical methods using the equations of Horowitz-Metzger (HM) and Coats-Redfern (CR).     

Treatment of phosphogypsum waste using suitable organic extractants

Phosphogypsum (PG) is a residue of the phosphate fertilizer industry that has relatively high concentrations of harmful radioactive materials. The reduction in concentration of the radionuclides from PG was investigated. The removal process is based on leaching of radionuclides using suitable organic extractants. The studied radionuclides were ²²⁶Ra, ²¹⁰Pb, ²³⁸U and ⁴⁰K. The factors affect the leaching process such as type of leaching materials, contact time, concentration of the desired solvent, liquid to solid ratio, and temperature were studied. Based on the experimental results, about 71.1, 76.4, 62.4, and 75.7% of ²²⁶Ra, ²¹⁰Pb, ²³⁸U and ⁴⁰K respectively were successfully removed from the PG. The reduction in the concentration of radionuclides was accompanied by reduction in the concentration of rare earth elements (∑REE) equals to 69.8%. Using the desired organic extractant under optimum conditions for treatment of the PG waste leads to obtain a decontaminated product that can be safely used in many industrial applications.     

Spectrophotometric determination of β-adrenergic antagonists drugs via ion-pair complex formation using MO and EBT

Two simple, rapid and sensitive spectrophotometric methods have been proposed for the assay of bisoprolol fumarate (BSF), propranolol hydrochloride (PRH), and timolol maleate (TIM) either in bulk or in pharmaceutical formulations. The methods are based on the reaction of the selected drugs with methyl orange (MO) and eriochrome black T in acidic buffers, after extracting in dichloromethane and measured quantitatively with maximum absorption at 428 and 518 nm for MO and EBT, respectively. The analytical parameters and their effects on the reported systems are investigated. The extracts are intensely colored and very stable at room temperature. The calibration graphs were linear over the concentration range of 0.8–6.4, 0.4–3.6, 0.8–5.6 μg/mL for BSF, PRH, and TIM, respectively, with MO and 0.8–6.4, 0.4–3.2, and 0.8–8.0 μg/mL for BSF, PRH, and TIM, respectively, with EBT. The stoichiometry of the complexes was found to be 1 : 1 in all cases. The proposed methods were successfully extended to pharmaceutical preparations. Excipients used as additive in commercial formulations did not interfere in the analysis. The proposed methods can be recommended for quality control and routine analysis where time, cost effectiveness and high specificity of analytical technique are of great importance.