High-performance liquid chromatographic method for the determination of nicardipine in pure, pharmaceutical preparations and plasma and its application to pharmacokinetics in humans

Abstract

A simple, sensitive and reproducible reversed-phase liquid chromatographic method has been developed and validated for the determination of nicardipine hydrochloride (NC) in pure, pharmaceutical preparations, human plasma and the study of the pharmacokinetics of the drug in human body. Nicardipine in plasma were extracted with hexane-butanol (12:1,v/v) after addition of borate buffer (0.5 M, pH=9.0), and then measured by HPLC-UV using a Waters Symmetry C18 column as stationary phase and methanol– triethylamine buffer (0.01M) pH 4 with acetic acid (70:30) as mobile phase. Nicardipine was quantified by ultraviolet absorbance at 353 nm. The method proved to be linear in the pure drug in the ranges of 15-200 ng/mL (r=0.9989) and 5-40 µg/mL (r=0.9995), and for the pharmaceutical preparations and plasma for drug concentrations in the range of 5-40 µg/mL (r =0.9992) and 25-150 ng/mL (r=0.9991), respectively. The lower limit of detection and the lower quantitation limit of NC in plasma were 11.74 and 35.57 ng/mL, respectively. The method is sensitive and reliable for pharmacokinetic studies of nicardipine in humans after the oral administration of immediate-release capsules to healthy subjects.