RESUMEN
Butorphanol tartrate is a synthetic opioid agonist-antagonist used as analgesic, possessing three chiral centres in the basic part of the molecule. Its chiral purity is routinely controlled only by optical rotation. A new capillary zone electrophoresis method, capable to separate the enantiomers of butorphanol and intermediate of its synthesis, cycloamine, was developed. Different electrolyte composition (type and concentration of carrier ion, pH, and organic solvent addition), and type and concentration of several chiral selectors (natural and modified cyclodextrins) were tested. Using the optimized conditions (acidic electrolyte with the addition of highly sulphated gamma-cyclodextrin) as low as 0.05% of undesirable enantiomers can be detected. Selected method characteristics, i.e., linearity (0-50 mg/l), precision (2.5% at 20 mg/l), and accuracy (101 +/- 2% at 20 mg/l) were evaluated. The optimized method was applied for the analysis of real batches of butorphanol and cycloamine. It was found that butorphanol tartrate manufactured by IVAX Pharmaceuticals contains less than 0.05% of undesirable enantiomer.
Asunto(s)
Butorfanol/análogos & derivados , Butorfanol/aislamiento & purificación , Electroforesis Capilar/métodos , Butorfanol/normas , Reproducibilidad de los Resultados , EstereoisomerismoRESUMEN
From the phosphate content in meat and meat protein a new ratio of free (non-protein) phosphate/protein (16±2 mg/g) was calculated. From the level of soluble phosphate determined by capillary isotachophoresis (CITP), protein content determined by Kjeldahl method and with the use of the earlier-mentioned ratio the amount of added phosphates could be calculated. The method was compared with the spectrophotometric dry-ashing reference method on 34 samples and good agreement was found.