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A flow-injection spectrometric method for determination of sodium diclofenac in pharmaceutical formulations was developed on this work. Sodium diclofenac solutions were injected into a stream of deionized water that reacted with potassium permanganate on acid medium producing Mn2+ ions whose exhibit maximum absorbance at 450 nm. The methodology used optimize experimental parameters was 33 factorial design and response surface. The proposed method obeyed the Beer’s Law over the range 25-160 mg L-1, applied in tablets and ampoules samples. Results were compare with the reference method. It was verified at the 95% confidence level, through paired t-test application – there is no statistic difference between them. The detection limit was valued in 2.6 mg L-1, relative standard deviation for 10 consecutive injections was 1.5% (100.0 mg L-1 sodium diclofenac solution) and the sample throughput was 80 samples h-1. Regarding optimization of operational conditions, the FIA spectrometric method presented analytical performance as good as other elaborated flow analyzers. Offers a simple and inexpensive way to this drug indirect determination aiming quality control on pharmaceutical industry’s assembly line. However, it can not be used for adulteration screening analysis due to non-selectivity and non-specificity of redox reactions.

The synthesis of carbonated hydrocalumites could be troublesome because the carbonate anions can precipitate as calcium carbonate, therefore the aging times should be reduced. In this paper, carbonated hydrocalumites were synthesized using an unique gel divided in two portions: a part was aging to temperature room for 30 min, and the other one, by microwave radiations for 2 min. Samples were characterized by different techniques such as: Fourier-transformed infrared spectroscopy, X-ray diffraction, BET surface measurements, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Then, they were tested as antacid using a synthetic gastric juice. Results showed that carbonated hydrocalumites aging by microwave radiations were more flawless than those obtained by the conventional method. Moreover, using microwave radiations, the aging times were notably reduced and the purity of carbonated hydrocalumites was improved. The antacid properties were similar for hydrocalumites synthesized by different ways. However, they showed they showed better antacid properties with higher antacid capacity than commercial antacid.

The mononuclear cobalt (III) complex derived from 1,10-phenanthroline with lactose [Co(phen)2lactose]Cl2·3H2O (1) has been prepared and its properties have been compared with the sucrose complex [Co(phen)2sucrose]Cl2·3H2O (2) and the complex without carbohydrate [Co(phen)2Cl2]Cl·3H2O (3).The chemical structure of (1) was assigned by 1H-NMR, IR, CD and UV-Vis spectral data. The antibacterial activity of (1) - (3) was evaluated by disc-diffusion assays, using Gram-negative and positive bacteria. The minimum inhibitory concentration of the three complexes on the studied bacteria and their cytotoxicity on HEK293 human cells was determined. A colorimetric plate assay was used to distinguish bacteriostatic from bactericidal effect. Finally, the complexes uptake mechanism was evaluated using bacteria with mutated genes that encode for carbohydrate and siderophore receptors. The results indicate that complex (1) has an antibacterial activity similar to (3), while (2) presents a more restricted one. Moreover, all three complexes act by a bacteriostatic effect against bacterial cells and both (1) and (3) use a siderophore uptake mechanism to enter on bacterial cytoplasm. Cytotoxicity assays show that carbohydrate complexes are not cytotoxic to human cells, in contrast with complex (3), which is highly toxic. These results suggest that the use of the lactose ligand would maintain the antibacterial activity and uptake mechanism of the complex at reasonable levels, and would also reduce its toxicity against human cells. Thus, its strategic use would allow a decrease in toxicity of complexes used in eventual studies on eukaryotic systems.

Thermal degradation of Poly(ethylene terephthalate) (PET) bottles waste was carried out by glycolysis using triethyleneglycol (TEG) as nucleophilic agent and N1,N2-bis(2-aminobenzyl)-1,2-diaminoethane zinc(II) (ABEN), in order to test this compound as catalyst in the degradation of PET until to obtain short chains of polyester (oligomers). The depolymerization processes was tested at 180, 190 and 210 °C, and two molar ratios of PET:TEG (1:1.3 and 1:2.6), the amount of catalyst used was fixed at 1% in relation to PET, the best experiment of PET glycolysis was found at 190 °C during two hours in a mass relation PET:TEG 1:1.3. All products were analyzed by Fourier transform infrared spectroscopy (IR), gel permeation chromatography (GPC) and differential scanning calorimetry (DSC), the behavior of the reaction rate was studied for the best experiment by measuring the amount of degraded PET at different glycolysis time. The degradation of PET was favored with the use of ABEN, which accelerates the reaction, obtaining oligomers in the absence of an organic solvent or reaction medium, this is the most efficient catalyst found so far. The oligomers were obtained with molecular weight between 900 and 1500 g mol-1 depending on the reaction time, 60 min was the less time of the total glycolysis of PET. Also was found that the molecular weight of the oligomers increased along the glycolysis, due to the recombination with TEG and ethylene glycol produced in degradation.

A new macrocycle Schiff base, by the reaction between benzene-1,2-diamine and 3-bromo-pentane-2,4-dione, is introduced and a series of its complexes with Co(II), Ni(II), Cu(II) and Zn(II) have been synthesized. FTIR, 1H and 13C NMR, and TGA, also biological activities of all complexes and the electronic spectral data have been investigated. The results show that there are no water molecules, also that macrocycle Schiff base is bonded to the metal ions through nitrogen atoms of four azomethine groups via an octahedral arrangement containing N4 tetra-dentate donor sites on planar and two Cl atoms occupying the other two opposed sites. The corresponding Cu(II) and Zn(II) complexes showed good antibacterial and antifungal activities. The molecular geometry, frontier molecular orbitals and Mulliken atomic charge of the compounds are investigated theoretically using DFT method.

The activity of Fe2O3/Al2O3 catalysts prepared by impregnation of Al2O3 with different amounts of Fe and calcination temperatures (650 and 900 ºC) in the direct N2O decomposition reaction was studied. High calcination temperature was introduced to study the effect of “aging”, which are the conditions prevailing in the process-gas option for N2O abatement. The catalysts were characterized by BET, XRD, UV-DRS, and H2-TPR. The incorporation of Fe promotes the alumina phase transition (g-Al2O3 to a-Al2O3) when the catalysts are calcined at 900 ºC, which is accompanied by a decrease in the specific area. The activity of the catalysts and the specific surface area depend on Fe loading and calcination temperature. It was found that highly dispersed Fe species are more active than bulk type Fe2O3 particles. We conclude that Fe2O3/Al2O3 catalysts prepared by impregnation method are active in the decomposition of N2O, to be used at low or high reaction temperatures (tail-gas or process-gas treatments, respectively), as part of nitric acid production plant.

Nanomaterials synthesize by different techniques exhibit excellent photocatalytic activity. These catalysts could be employed for environmental remediation, renewable energy sources, photocatalysis and many other applications in various fields. Nanophotocatalyst has been used for the treatment of hazardous materials such as industrial effluents containing complex organic compounds, dyes and metal ions successfully. The multidimensional study of composition, shape, size, surface area and nanostructure and different operating parameters like pH, concentration, temperature etc, of these photocatalyst help in current and further development of photocatalysts for different applications . The photocatalytic activity of nanoparticles has made a great contribution in providing definitive mechanistic information about the photocatalytic processes.The main aim of this review paper is to give an overview of the enhanced photocatalytic activities of titanium dioxide (TiO2) nanoparticles. This review includes the basic properties of photocatalyst and mechanim of photocatalysis process followed by unique photocatalytic properties and research of TiO2 nanoparticles as photocatalysts. An effort has also been made to give an overview of expedient photocatalytic activity of these doped nanoparticles. Many investigators have reported the enhanced photocatalytic activity by the degradation of dyes as a model compound.

In this work, a matrix based on silica xerogel, synthesized from TEOS, water, ibuprofen (as template) and acetic acid at room temperature, was used for ibuprofen (IBF) incorporation, aiming to create a drug delivery system capable of releasing this compound under a basic pH condition (considering desirable and optimal release in the intestines). The IBF release was checked at different pH values (ranging from 2 to 8), using appropriate buffered solutions. After observing the IBF release performance from the silica xerogel and its dependence on the pH, the same matrix containing IBF was submitted to a novel assay, using only a pH 7 buffered solution as the best way to check the chronological release. This was carried out at 1, 2, 5 and 10 minutes to determine aliquot removal, as well as IBF concentration at each elapsed period.

UPLC-MS analytical procedure has been established for the determination of adrenaline in marketed formulation and in the pure form. The detection of the adrenaline was executed considering positive electrospray ionization (ESI) and selected ion reaction (SIR) modes. Chromatographic separation was achieved using ACQUITY UPLC BEH C18 column (100 mm × 2.1 mm, 1.7 μm particles size) using a binary mobile phase mixture of methanol and water (50:50). The mobile phase was set to flow at the rate of 0.3 ml min-1. The run time time for adrenaline was as short as 1.5 minutes. Linearity was found to be over the concentration range of 1μg ml-1 - 6μg ml-1. An excellent recovery of 100.18 % - 100.68 % was achieved using this procedure. The standard deviation ranged from 0.014 - 0.118 in intra-day studies and 0.016 - 0.096 in case of inter-day studies. The procedure’s quantitation limit was 0.76μg ml-1 and detection limit was 0.25 μg ml-1. The method was successfully applied to determine adrenaline in drug formulations. In order to get the information about the stability of adrenaline in various environments forced degradation studies were conducted and the characterization of the stressed samples were performed using mass spectrometry.

Phthalic acid as a green, biodegradable economical and environmentally benign nature catalyst for the one-pot three-component Biginelli synthesis of 3,4-dihydropyrimidin-2-(1H)-one derivatives via β-keto esters, aldehyde derivatives and urea/thiourea under thermal and solvent-free conditions and one-pot four-component domino condensation of substituted dihydro-2-oxypyrrole by reaction of dialkyl acetylenedicarboxylate, formaldehyde and amines (aromatic and aliphatic) under ambient temperature with short reaction times and excellent yields is reported. The most benefits this procedure are such as green, biodegradable, inexpensive and non-toxic catalyst, eco-friendly, high catalytic activity, efficient, easily separation with no column chromatographic separation, simple operational procedures, one-pot, excellent yields, environmentally benign nature.