title: Pharmacokinetic study of ACT-132577 in rat plasma by ultra performance liquid chromatography-tandem mass spectrometry.
abstract: It was reported that macitentan was metabolized predominantly by cytochrome P450 3A4, and ACT-132577, its pharmacologically active metabolite, is fivefold less potent at blocking ET receptors than macitentan. In this work, a sensitive and selective ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for determination of ACT-132577 in rat plasma was developed and validated. After addition of diazepam as an internal standard (IS), protein precipitation by acetonitrile was used to prepare samples. Chromatographic separation was achieved on a UPLC BEH C18 column (2.1 mm × 100 mm, 1.7 μm) with 0.2% formic acid and methanol as the mobile phase with gradient elution. An electrospray ionization source was applied and operated in positive ion mode; multiple reactions monitoring (MRM) mode was used for quantification using target fragment ions m/z 546.9→200.6 for ACT-132577, and m/z 285.1→193.1 for IS. Calibration plots were linear throughout the range 10-4000 ng/mL for ACT-132577 in rat plasma. Mean recovery of ACT-132577 in rat plasma ranged from 82.6% to 90.6%, matrix effect of ACT-132577 in rat plasma ranged from 101.4% to 115.2%. RSD of intra-day and inter-day precision were both less than 11%. The accuracy of the method ranged from 96.1% to 103.5%. The method was successfully applied to pharmacokinetic study of ACT-132577 after oral and intravenous administration of macitentan.
authors.affiliation: Department of Clinical Lab Medicine, Taizhou Municipal Hospital affiliated with Taizhou University Taizhou 318000, Zhejiang, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: The Laboratory of Clinical Pharmacy, The People's Hospital of Lishui Lishui 323000, Zhejiang, China.
authors.forename: Peiwu
authors.initials: P
authors.lastname: Geng
authors.affiliation: Department of Clinical Lab Medicine, Taizhou Municipal Hospital affiliated with Taizhou University Taizhou 318000, Zhejiang, China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Luo
authors.affiliation: Department of Anesthesiology, Maternity and Child Care of Lishui Lishui 323000, Zhejiang, China.
authors.forename: Genzhi
authors.initials: G
authors.lastname: Zhou
authors.affiliation: Laboratory Animal Centre, Wenzhou Medical University Wenzhou 325035, Zhejiang, China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Laboratory Animal Centre, Wenzhou Medical University Wenzhou 325035, Zhejiang, China.
authors.forename: Lijing
authors.initials: L
authors.lastname: Zhang
authors.affiliation: The Laboratory of Clinical Pharmacy, The People's Hospital of Lishui Lishui 323000, Zhejiang, China.
authors.forename: Shuanghu
authors.initials: S
authors.lastname: Wang
authors.affiliation: Laboratory Animal Centre, Wenzhou Medical University Wenzhou 325035, Zhejiang, China.
authors.forename: Congcong
authors.initials: C
authors.lastname: Wen
authors.affiliation: Laboratory Animal Centre, Wenzhou Medical University Wenzhou 325035, Zhejiang, China.
authors.forename: Jianshe
authors.initials: J
authors.lastname: Ma
authors.affiliation: The Laboratory of Clinical Pharmacy, The People's Hospital of Lishui Lishui 323000, Zhejiang, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Ding
keywords: ACT-132577; UPLC-MS/MS; pharmacokinetics; rat