Vortex-assisted ionic liquid microextraction coupled to flame atomic absorption spectrometry for determination of trace levels of cadmium in real samples

A simple and rapid vortex assisted ionic liquid based liquid-liquid microextraction technique [VALLME] was proposed for preconcentration of trace levels of cadmium. According to this method, the extraction solvent was dispersed into the aqueous samples by the assistance of vortex agitator. Cadmium preconcentration was mediated by chelation with the 8-hydroxyquinoline; [oxine] reagent and an IL, 1-octyl-3-methylimidazolium hexafluorophosphate [[Omim][PF[6]] was chosen as the extraction solvent to extract the hydrophobic complex. Several variables such as sample pH, concentration of oxine, volume of [Omim][PF[6]] and extraction time were investigated in details and optimum conditions were selected. Under the optimum conditions, the limit of detection [LOD] was 2.9 microg L[-1] for Cd [] and relative standard deviation [RSD%] for five replicate determinations of 125 microg L[-1] was 4.1%. The method was successfully applied to the determination of cadmium in tap water, apple and rice samples

Radiosynthesis and biological evaluation of [111]in-tris [8-hydroxy-2-methylquinoline] complex as a possible imaging agent

Due to the interesting pharmacological properties of radiolabeled metal oxine derivatives such as cell internalization, tumor avidity and antiproteosome activity, [111]In-tris[8-Hydroxy-2-methylquinoline] [[111]In-HMQ] was developed in this study. [111]In-HMQ was prepared using [111]InCl[3] and 8-Hydroxy-2-methylquinoline [HMQ] for 60 min at 100[degree sign] C [radiochemical purity: >99% ITLC, >99% HPLC, specific activity: 13-14 GBq/mmol]. Stability of the complex was checked in final formulation and in the presence of human serum for 48 h. The partition coefficient was calculated for the compound [log P=0.68]. The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies and SPECT up to 24 h. A detailed comparative pharmacokinetic study for [111] In cation and [111]In-HMQ are performed up to 24h. The complex is mostly cleaned from the circulation by kidneys and is a compound rapidly washing from the circulation. The biodistribution of the complex in tumor models is on-going

[66Ga] oxine complex; preparation and stability as a possible PET radiopharmaceutical

Gallium-66 [T1/2= 9.49 h] is an interesting radionuclide that has potential for positron emission tomography [PET] imaging of biological processes in intermediate to slow target tissue uptake. Oxine has been labeled with this radioisotope in the form of [66Ga]gallium chloride for its possible diagnostic properties. Materials and methods: 66Ga was produced in the 30 MeV cyclotron [Cyclon-30, IBA] via the 66Zn[p,n]66Ga reaction.TLC was performed on polymer backed silica gel. A Gamma spectrometer HPGe detector was used for countings. After the bombardment, the production yield was 11.2 mCi/ m Ah. The [66Ga]Oxine complex was obtained at the pH=5 in phosphate buffer medium at 37°C in 10 minutes. Radio-TLC showed an overall radiochemical yield of 97% [radiochemical purity > 98%]. The chemical stability of the complex was checked in vitro with a specific activity of 896 mCi/ml. [66Ga]oxine can be used in diagnostic studies due to its suitable physico-chemical properties both in vitro and in vivo

Further phenotypic characterization of pso mutants of Saccharomyces cerevisiae with respect to DNA repair and response to oxidative stress

The sensitivity responses of seven pso mutants of Saccharomyces cerevisiae towards the mutagens N-nitrosodiethylamine (NDEA), 1,2:7,8-diepoxyoctane (DEO), and 8-hydroxyquinoline (8HQ) further substantiated their allocation into two distinct groups: genes PSO1 (allelic to REV3), PSO2 (SNM1), PSO4 (PRP19), and PSO5 (RAD16) constitute one group in that they are involved in repair of damaged DNA or in RNA processing whereas genes PSO6 (ERG3) and PSO7 (COX11) are related to metabolic steps protecting from oxidative stress and thus form a second group, not responsible for DNA repair. PSO3 has not yet been molecularly characterized but its pleiotropic phenotype would allow its integration into either group. The first three PSO genes of the DNA repair group and PSO3, apart from being sensitive to photo-activated psoralens, have another common phenotype: they are also involved in error-prone DNA repair. While all mutants of the DNA repair group and pso3 were sensitive to DEO and NDEA the pso6 mutant revealed WT or near WT resistance to these mutagens. As expected, the repair-proficient pso7-1 and cox11-Delta mutant alleles conferred high sensitivity to NDEA, a chemical known to be metabolized via redox cycling that yields hydroxylamine radicals and reactive oxygen species. All pso mutants exhibited some sensitivity to 8HQ and again pso7-1 and cox11-Delta conferred the highest sensitivity to this drug. Double mutant snm1-Delta cox11-Delta exhibited additivity of 8HQ and NDEA sensitivities of the single mutants, indicating that two different repair/recovery systems are involved in survival. DEO sensitivity of the double mutant was equal or less than that of the single snm1-Delta mutant. In order to determine if there was oxidative damage to nucleotide bases by these drugs we employed an established bacterial test with and without metabolic activation. After S9-mix biotransformation, NDEA and to a lesser extent 8HQ, lead to significantly higher mutagenesis in an Escherichia coli tester strain WP2-IC203 as compared to WP2, whereas DEO-induced mutagenicity remained unchanged

Spectroscopic studies of new asymmetrical Schiff base compounds derived from 7-formyl-8-hydroxyquinoline with aliphatic and aromatic diamines and beta-diketones

The electronic absorption spectra of some new assyrnmetrical Schiff bases derived from 7-formyl-8-hydroxyquinoline[FHQ] with different diamines and beta-diketones are investigated in organic solvents of varying polarities. The important bands in the IR spectra of the compounds as well as the main signals of the [1]H NMR spectra are discussed in relation to molecular structure. Mass spectra and the mechanism leading to different fragment ions of the compounds are also discussed

Tomografia por emissäo de fóton único em epilepsia temporal: estudos intercríticos e críticos com análise visual e semi quantitativa / Single photon emission tomography in temporal epilepsy: interictal and ictal studies with visual and semi quantitative analysis

Vinte e oito estudos intercríticos e 9 críticos/pós críticos de tomografia por emissäo de fóton único (SPECT) foram realizados em 27 pacientes com epilepsia do lobo temporal e esclerose mesial temporal. Estudos intercríticos localizaram corretamente a área epileptogênica em 19 (67 por cento) dos pacientes pela análise visual e 16 (61,5 por cento) pela semi quantitativa, com 10,7 e 15,3 por cento, de falsa lateralizaçä respectivamente. Todos os 9 estudos críticos/ pós críticos detectaram o hemosfério epileptogênico e permitiram localizaçäo correta da área epileptogênica em 5 de 9 pacientes cujos exames intercríticos haviam sido inonclusivos. Três estudos realizados durante crises secundariamente generalizadas e simétricas mostraram hiperfluxo restrito ao lobo temporal

Derivados azoicos da oxina com sulfas potencialmente antimalaricas / Oxine azoic derivatives with potentially antimalarial sulfonamides

Com o objetivo de obter farmacos potencialmente antimalaricos prepararam-se, pelo processo de hibridacao molecular, cinco compostos mediante reacao do sal de diazonio e sulfas antimalaricas - sulfadiazina, sulfadoxina, sulfametoxipiridazina, sulfametoxazol e sulfamonometoxina - com a oxina (8-hidroxiquinolina). Submetidos a analises espectrometricas - IV, UV, RMP -, os derivados apresentaram caracteristicas das estruturas propostas

Effect of metal chelators on thermoluminescence peaks of spinach chloroplasts and photosystem II particles: probing the water oxidation cycle with 8-hydroxyquinoline.

Inhibition of photosystem II (PS II) activity by 8-hydroxyquinoline (8-HQ) has been investigated in case of spinach chloroplasts and isolated photosystem II particles using the thermoluminescence technique. In presence of 8-HQ, water to methylviologen (MV) photoreduction in isolated chloroplasts is inhibited while the reduction of dichlorophenol indophenol is inhibited in both chloroplasts as well as in photosystem II particles. The activity can be restored fully by addition of diphenylcarbazide (DPC), suggesting that the donor side of water oxidation complex is affected. The changes in the thermoluminescence peaks indicate that the charge recombination processes involving S2 or S3 states of the Kok's cycle are probably affected by 8-HQ treatment.

Self adduct formation in the extraction of uranium [VI] chelate of 8-quinolinol

Tremendous amount of work has been done on the metal chelate system in which any one kind of ligand is involved in chelation. The effect of such factors as ligand basicities, sizes of chelate rings, steric factors and metal ion acidity have been evaluated in the formation of a chelate from the aquated metal ion and the chelating agent. The extraction of coordination - unsaturated chelates can, in some cases, be favoured by the use of an excess of chelating agent. Despite the contributions from several authors to the formation of uranium oxinate complexes, it is interesting that the composition and other characteristics of the extracting uranium-oxine system are not established with certainty. The present study attempts to throw more light on these aspects

Efeito espermicida da associaçäo ácido bórico/sulfato de 8-hidroxiquinolina em pessários de manteiga de cacau (Parte II) / Spermicidal effect of the association boric acid/8-hydroxichinolin sulfate in vaginal suppository of cacao butter (Part II)

Os autores demonstram, usando a prova de Sims-Huhner, que o uso da associaçäo ácido bórico/quinosol em pessários de manteiga de cacau apresenta marcante efeito espermicida em todas as pacientes estudadas

Efeito espermicida in vitro da associaçäo ácido bórico-sulfato de 8-hidroxiquinolina em pessários de manteiga de cacau / In vitro spermicidal effect of the combination of acid 8-hydroxyquinoline sulfate in vaginal suppository of cacao's butter

O autor demonstra, com técnica própria in vitro, que a associaçäo ácido bórico-quinosol apresenta marcante feito espermicida em 100% da populaçäo de espermatozóides em 10 lotes de sêmen humano testados

Spectrophotometric studies on the Al, Ga and in chelates with 5- [2-hydroxy-5-sulphophenylazo] -8-quinolinol

Trivalent ions of Al, Ga and In form colored complexes with 5 - [2-, hydroxy - 5-8 sulphaphenylazo] -8- quinolinol. The complexes were used satisfactorily for the photometric determination of the metal ions. The optimum conditions for the formation of the complexes were extensively investigated. Universal buffers of pH 6.6, 4.5 and 6.60 were used for Al, Ga and In respectively. The stoichiometry of the formed complexes and their stability constants were determined spectrophotometrically. The interference of many metal ions in the determination was also investigated. Beer's law is obeyed up to 0.67, 1.7 and 3.44 ppm metal ion. A Spectrophotometric titration of Ga with EDTA proved to be successful