RESUMO
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
The distribution and magnitude of vitamin A deficiency and dietary consumption of 161 children at 6 to 72 months of age in rural zones in Cansancao-Bahia-Brazil were evaluated. The serum retinol levels were measured by the spectrophotometric method (Bassey-Lowry modified by Araujo and Flores). The serum retinol average was found to be distributed homogeneously throughout the different age groups. Inadequate serum retinol levels (<20,0 mu g/dl) were detected in 44.7% of the children, which characterized the deficiency as constituting a public health problem. The serum retinol levels showed no statistically significant association as between the sex and age of the children; however the children of less than 24 months showed a higher prevalence of inadequate serum retinol levels. The main available source of vitamin A for these children was represented by carotenoids, especially beta-carotene. Foods regarded as being rich in vitamin A were consumed by all age groups. The greatest diversification of consumption of foodstuffs with moderate and low vitamin A content was observed in the group of children of from 24 to 72 months of age, through this was no guarantee of adequate serum retinol levels in this group however.