Bioanalytical Department, Integrated Product Development, Dr. Reddy's Laboratories Ltd, Bachupalli, Hyderabad 500 072, India.
J Chromatogr B Analyt Technol Biomed Life Sci. 2011 Sep 15;879(26):2827-33. doi: 10.1016/j.jchromb.2011.08.006. Epub 2011 Aug 11.
A highly sensitive, selective and evaporation free SPE extraction, ESI-LC-MS/MS method has been developed for estimation of misoprostol free acid in human plasma using misoprostol acid-d(5) as an internal standard (IS). The analyte was separated using isocratic mobile phase on reverse phase column and analyzed by MS/MS in the multiple reaction monitoring mode using the respective [M-H] anions, m/z 367-249 for misoprostol acid and m/z 372-249 for the IS. The total run time was 5.0 min and the elution of misoprostol acid and misoprostol acid-d(5) (IS) occurred at 3.6 min. The developed method was validated in human plasma with a lower limit of quantification of 2.5 pg/mL. A linear response function was established for the range of concentrations 2.5-1200 pg/mL (r>0.998) for misoprostol acid in human plasma. The intra and inter-day precision values for misoprostol acid met the acceptance as per FDA guidelines. Misoprostol acid was stable in the battery of stability studies viz., bench-top, auto-sampler and freeze/thaw cycles. The developed assay method was applied to an oral pharmacokinetic study in humans.
已开发出一种高灵敏度、选择性且无蒸发的 SPE 提取、ESI-LC-MS/MS 方法，用于使用米索前列酸-d(5)作为内标 (IS) 来估算人血浆中的米索前列醇游离酸。使用反相柱在等度流动相下分离分析物，并通过 MS/MS 在多重反应监测模式下进行分析，使用各自的 [M-H] 阴离子，m/z 367-249 用于米索前列酸和 m/z 372-249 用于 IS。总运行时间为 5.0 分钟，米索前列醇酸和米索前列醇酸-d(5) (IS) 的洗脱时间为 3.6 分钟。该方法在人血浆中进行了验证，定量下限为 2.5 pg/mL。已建立米索前列醇酸在人血浆中的浓度范围为 2.5-1200 pg/mL (r>0.998) 的线性响应函数。根据 FDA 指南，米索前列醇酸的日内和日间精密度值符合要求。米索前列醇酸在一系列稳定性研究中稳定，即台式、自动进样器和冻融循环。所开发的测定方法已应用于人体口服药代动力学研究。
