Determination of RKI-1447 in rat plasma by UPLC–MS/MS and investigation on its pharmacokinetics, an effective ROCK1 and ROCK2 inhibitor

RKI-1447 is an effective ROCK1 and ROCK2 inhibitor, having anti-invasion and anti-tumor activity. In this study, we used ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) to detect RKI-1447 in rat plasma and investigated its pharmacokinetics in rats. Diazepam was utilized as an internal standard, and an acetonitrile precipitation method was used to process the plasma samples. Chromatographic separation was achieved using a UPLC ethylene bridged hybrid (BEH) column (2.1 mm × 50 mm, 1.7 μm) with a gradient acetonitrile–water mobile phase (containing 0.1% formic acid). Flow rate was set at 0.4 mL/min. Electrospray ionization (ESI)–tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization was applied: m/z 327.1 → 204.0 and 285.1 → 193.3 for RKI-1447 and internal standard, respectively. The results indicated that within the range of 10–2000 ng/mL, the linearity of RKI-1447 in rat plasma was acceptable (r > 0.995), and the lowest limit of quantification (LLOQ) was 10 ng/mL. Intra-day precision RSD of RKI-1447 in rat plasma was lower than 8%, and inter-day precision RSD was lower than 11%. Accuracy range was between 91.6% and 107.1%, and the matrix effect was between 85.1% and 87.0%. The analysis method was sensitive and fast with suitable selectivity, and was successfully applied in the pharmacokinetics of RKI-1447 in rats. The bioavailability of the RKI-1447 was 7.3%.

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Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).