RESUMO
Rifaximin, an oral antimicrobial, has no standardized analytical methods in many official compendia. In this context, the aim was to develop and validate an analytical method by capillary electrophoresis for quantification of rifaximin in tablets. The choice of capillary electrophoresis was based on the concepts of green analytical chemistry, taking into account the health of the operator and environment, analytical conscience, as well as the parameters of linearity, selectivity, precision, accuracy and robustness. The method was linear between 50 and 500 µg mL-1 (r = 0.9993) using purified water and ethanol in the sample preparation, silica capillary, borate buffer 25 mM pH 9.5, 20 kV and 290 nm. It presented good precision intraday (1.30%) and interday (1.56%). The accuracy complied with average recovery of 100.24%, as well as selectivity in the presence of impurities and degradation products and robustness against variations in the concentration, pH, rinse time of the buffer, voltage, wavelength, injection time and temperature. The capillary electrophoresis method developed for the evaluation of rifaximin tablets is low cost, fast, miniaturized, clean and environmentally friendly and can be used by laboratories and chemical and pharmaceutical industries for quality control of the drug.
Assuntos
Antibacterianos/análise , Eletroforese Capilar/métodos , Rifaximina/análise , Limite de Detecção , Controle de Qualidade , Comprimidos/análiseRESUMO
Amino acids play an important role in clinical analysis. Capillary electrophoresis-electrospray ionization-mass spectrometry (CE-ESI-MS) has proven to possess several characteristics that make it a powerful and useful tool for the analysis of amino acids in clinical studies. Here we present a method for the separation and quantitative analysis of 27 amino acids in urine based on CE-ESI-MS. The method presents an improved resolution between the isomers Leu, Ile, and aIle, in comparison to other CE-ESI-MS methods in the literature. This method is fast, selective, and simple and has improved sensitivity by applying a pH-mediated stacking strategy, showing that it can be successfully used for amino acid analysis and probably for other small cationic metabolites.
Assuntos
Aminoácidos/urina , Eletroforese Capilar/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Concentração de Íons de Hidrogênio , Isoleucina/urina , Leucina/urinaRESUMO
A selective and rapid capillary zone electrophoresis method for determination of the multicomponent aminoglycoside antibiotic gentamicin is described. Baseline separation of gentamicin C1, C1a, C2, C2a and C2b components was achieved with a background electrolyte containing 0.35 mM cetyl trimethylammonium bromide, 3% methanol and 90 mM sodium pyrophosphate (pH 7.4) and detected directly with UV detection without derivatization. Quantitative analysis was performed and illustrated the potential use of capillary electrophoresis for the identification and quantitation of gentamicin components, but the application of this method is limited to a gentamicin concentration range of 2-6 mg/ml.