RESUMO
OBJECTIVE:To study the compatible stability of doxofylline injection and dexmethasone sodium phosphate injection.METHODS:The changes in appearance and pH value of the mixture of doxofylline injection and dexmethasone sodium phosphate injection in 5%glucose injection within 6 hours at 25℃were observed and determined,the content of which was determined by HPLC.RESULTS:Compared with the solution at 0h of mixing,no significant changes were noted in color,clarity and content within 6 hours' mixing,however,there was an increase in its pH value.CONCLUSION:The mixture of doxophylline and dexmethasone in 5%glucose injection is stable in quality within 6 hours' mixing at 25℃.
RESUMO
OBJECTIVE:To establish a method for the determination of4major caffeine metabolites and to discuss the significance of which in the evaluation of the activity of drug-metabolizing enzyme CYP1A2.METHODS:The caffeine metabolites in the urine like5-acetylamino-6-formamido-3-methyluric acid(AFMU),1-methyluric acid(1U),1-methylxanthine(1X)and1,7-dimethyluricacid(17U)were determined by RP-HPLC gradient elution method,the ratios of metabolins(AFMU+1X+1U)/17U was calculated,the frequency distribution histogram was drawn and the activity of CYP1A2was evaluated.RESULTS:The mean value of the ratio of the metabolins in the subjects was4.27,which was in normal distribution.CONCLUSION:The method is simple,accurate and rapid,which is suitable for the determination of caffeine metabolites in urine and the study of the activities of CYP1A2.