Ku Hei-Young, Shon Ji-Hong, Liu Kwang-Hyeon, Shin Jae-Gook, Bae Soo Kyung
Department of Pharmacology, Inje University College of Medicine, Jin-Gu, Busan, South Korea.
J Chromatogr B Analyt Technol Biomed Life Sci. 2009 Jan 1;877(1-2):95-100. doi: 10.1016/j.jchromb.2008.11.015. Epub 2008 Nov 14.
A rapid and sensitive LC-MS/MS method for the determination of vardenafil and its major metabolite, N-desethylvardenafil, in human plasma using sildenafil as an internal standard was developed and validated. The analytes were extracted from 0.25-mL aliquots of human plasma by liquid-liquid extraction, using 1 mL of ethyl acetate. Chromatographic separation was carried on a Luna C(18) column (50 mm x 2.0 mm, 3 microm) at 40 degrees C, with an isocratic mobile phase consisting of 10 mM ammonium acetate (pH 5.0) and acetonitrile (10:90, v/v), a flow rate of 0.2 mL/min, and a total run time of 2 min. Detection and quantification were performed using a mass spectrometer in the selected reaction-monitoring mode with positive electrospray ionization at m/z 489.1-->151.2 for vardenafil, m/z 460.9-->151.2 for N-desethylvardenafil, and m/z 475.3-->100.1 for the internal standard (IS), respectively. This assay was linear over a concentration range of 0.5-200 ng/mL with a lower limit of quantification of 0.5 ng/mL for both vardenafil and N-desethylvardenafil. The coefficient of variation for the assay precision was <13.6%, and the accuracy was >93.1%. This method was successfully applied to a pharmacokinetic study after oral administration of vardenafil 20mg tablet in Korean healthy male volunteers.
建立并验证了一种快速、灵敏的液相色谱-串联质谱法，以西地那非为内标，用于测定人血浆中的伐地那非及其主要代谢物N-去乙基伐地那非。通过液-液萃取，用1 mL乙酸乙酯从0.25 mL人血浆等分试样中提取分析物。色谱分离在Luna C(18)柱(50 mm×2.0 mm, 3 µm)上于40℃进行，等度流动相由10 mM乙酸铵(pH 5.0)和乙腈(10:90, v/v)组成，流速为0.2 mL/min，总运行时间为2 min。采用质谱仪在选择反应监测模式下进行检测和定量，正电喷雾电离，伐地那非的m/z为489.1→151.2，N-去乙基伐地那非的m/z为460.9→151.2，内标(IS)的m/z为475.3→100.1。该测定法在0.5-200 ng/mL的浓度范围内呈线性，伐地那非和N-去乙基伐地那非的定量下限均为0.5 ng/mL。测定精密度的变异系数<13.6%，准确度>93.1%。该方法成功应用于韩国健康男性志愿者口服20 mg伐地那非片后的药代动力学研究。
