A sensitive and specific liquid-chromatography tandem mass spectrometry(LC-MS/MS)assay has been developed and validated for the simultaneous quantification of ivabradine and its active metabolite N-desmethylivabradine...A sensitive and specific liquid-chromatography tandem mass spectrometry(LC-MS/MS)assay has been developed and validated for the simultaneous quantification of ivabradine and its active metabolite N-desmethylivabradine in human plasma and urine.The assay employed a single liquid–liquid extraction of the analytes from plasma and urine samples,and diazepam was used as internal standard(IS).The chromatographic separation was achieved on a Diamonsil C18 column(150 mm4.6 mm,5 mm,Dikma)using a mixture of methanol and aqueous 5 mM ammonium acetate buffer containing 0.2%formic acid(80:20,v/v)as mobile phase.The assay for ivabradine and N-desmethylivabradine in plasma showed good linearity(r≥0.99)over the ranges 0.1013–101.3 ng/mL and 0.085–25.5 ng/mL,respectively.The assay for ivabradine and N-desmethylivabradine in urine showed good linearity(r≥0.99)over the ranges 10.13–6078 ng/mL and 8.5–850 ng/mL,respectively.The intra-and inter-day accuracy and precision values were found to be within the assay variability limits(RSD<15%)in accordance with FDA guidelines.The methods were successfully used for evaluating the pharmacokinetic properties of ivabradine and N-desmethylivabradine in human plasma and urine in Chinese healthy volunteers.展开更多
文摘A sensitive and specific liquid-chromatography tandem mass spectrometry(LC-MS/MS)assay has been developed and validated for the simultaneous quantification of ivabradine and its active metabolite N-desmethylivabradine in human plasma and urine.The assay employed a single liquid–liquid extraction of the analytes from plasma and urine samples,and diazepam was used as internal standard(IS).The chromatographic separation was achieved on a Diamonsil C18 column(150 mm4.6 mm,5 mm,Dikma)using a mixture of methanol and aqueous 5 mM ammonium acetate buffer containing 0.2%formic acid(80:20,v/v)as mobile phase.The assay for ivabradine and N-desmethylivabradine in plasma showed good linearity(r≥0.99)over the ranges 0.1013–101.3 ng/mL and 0.085–25.5 ng/mL,respectively.The assay for ivabradine and N-desmethylivabradine in urine showed good linearity(r≥0.99)over the ranges 10.13–6078 ng/mL and 8.5–850 ng/mL,respectively.The intra-and inter-day accuracy and precision values were found to be within the assay variability limits(RSD<15%)in accordance with FDA guidelines.The methods were successfully used for evaluating the pharmacokinetic properties of ivabradine and N-desmethylivabradine in human plasma and urine in Chinese healthy volunteers.
