RESUMO
In Brazil, the state of São Paulo contains both preserved areas (Juréia-Itatins Ecological Station) and extremely impacted ones (Cubatão Municipality). This study evaluated the concentrations of five metals (Cu, Cd, Cr, Pb, and Hg) in two mangroves with different levels of anthropogenic impact and the apparent genotoxicity to Ucides cordatus. Water and sediment samples were obtained, and metal concentrations were determined with an atomic absorption spectrophotometer. The genotoxic impact was quantified based on the number of micronucleated cells per 1,000 analyzed (MN), using hemolymph slides stained with Giemsa. Metal concentrations in water were below the detection limit, except for lead, although no significant difference was observed between the areas (P > 0.05). Sediment from Cubatão had higher concentrations of Cd, Pb, Cr, and Cu than sediment from Juréia-Itatins (P < 0.05), but no significant differences in metal concentrations were detected among depth strata of the sediment (P > 0.05). Crabs from Cubatão had a 2.6 times higher mean frequency of micronucleated cells (5.2 ± 1.8 MN) than those from Juréia-Itatins (2.0 ± 1.0 MN; P < 0.0001). The more-polluted conditions found in the mangrove sediments of Cubatão were reflected in the micronucleus assay, demonstrating their genotoxic effect; however, genetic damage should be attributed to a synergistic effect with other kinds of pollutants previously recorded in different environments of Cubatão. U. cordatus proved to be an excellent bioindicator of mangrove pollution. This study established, for the first time, the normal frequency of MN in a population of this species within an ecological station.
Assuntos
Braquiúros/fisiologia , Monitoramento Ambiental , Metais/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Animais , Brasil , Conservação dos Recursos Naturais/métodos , Ecossistema , Hemolinfa , Metais/toxicidade , Espectrofotometria Atômica , Poluentes Químicos da Água/toxicidadeRESUMO
A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method for the quantification of bromopride I in human plasma is presented. Sample preparation consisted of the addition of procainamide II as the internal standard, liquid-liquid extraction in alkaline conditions using hexane-ethyl acetate (1 : 1, v/v) as the extracting solvent, followed by centrifugation, evaporation of the solvent and sample reconstitution in acetonitrile. Both I and II (internal standard, IS) were analyzed using a C18 column and the mobile-phase acetonitrile-water (formic acid 0.1%). The eluted compounds were monitored using electrospray tandem mass spectrometry. The analyses were carried out by multiple reaction monitoring (MRM) using the parent-to-daughter combinations of m/z 344.20 > 271.00 and m/z 236.30 > 163.10. The areas of peaks from analyte and IS were used for quantification of I. The achieved limit of quantification was 1.0 ng/ml and the assay exhibited a linear dynamic range of 1-100.0 ng/ml and gave a correlation coefficient (r) of 0.995 or better. Validation results on linearity, specificity, accuracy, precision and stability, as well as application to the analysis of samples taken up to 24 h after oral administration of 10 mg of I in healthy volunteers demonstrated the applicability to bioequivalence studies.
Assuntos
Cromatografia Líquida de Alta Pressão , Antagonistas de Dopamina/sangue , Antagonistas de Dopamina/farmacocinética , Metoclopramida/análogos & derivados , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Metoclopramida/sangue , Metoclopramida/farmacocinética , Equivalência TerapêuticaRESUMO
PURPOSE: A sensitive, robust, and selective liquid chromatographic-tandem mass spectrometric method (LC-MS/MS) was developed and validated for paroxetine quantification in human EDTA plasma. METHODS: Sample preparation was based on liquid-liquid extraction using a mixture of ethyl acetate/hexane (50/50; v/v) to extract the drug and internal standard from plasma. Chromatography was performed on a C-18 analytical column and the retention times were 1.6 and 1.7 for paroxetine and fluoxetine (IS), respectively. The ionization was optimized using ESI(+) and selectivity was achieved by tandem mass spectrometric analysis using MRM functions, 330.0 --> 70.0 and 310 --> 43.9 for paroxetine and fluoxetine. RESULTS: Analytical curve ranged from 0.2 to 20.0 ng/mL. Inter-day precision and accuracy of the quality control (QC) samples were < 15% relative standard deviation (RSD). Analyte stability during sampling processing and storage were established. CONCLUSION: Validation results on linearity, specificity, accuracy, precision as well as application to the analysis of samples taken up to 120 h after oral administration of 20 mg of paroxetine in 28 healthy volunteers were found to be of good performance in bioequivalence study.