TITLE:
Determination of Ozanimod in Human Plasma by Using Liquid Chromatography-Tandem Mass Spectrometry
AUTHORS:
Nihal Saraner, İlayda Akgül, Berrak Güney, Onursal Sağlam
KEYWORDS:
Ozanimod, Ozanimod-D6, Human Plasma, LC-MS/MS, Bioanalytical Method Validation
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.16 No.10,
October
26,
2026
ABSTRACT: A rapid, sensitive and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantitative determination of ozanimod in human plasma. Plasma samples were prepared using protein precipitation with acetonitrile followed by evaporation and reconstitution. Chromatographic separation was achieved on an InertSustain AQ-C18 column (3 µm, 4.6 × 75 mm) using gradient elution at a flow rate of 1.2 mL/min. Detection was performed using electrospray ionization in positive-ion mode with multiple reaction monitoring (MRM). The monitored transitions were m/z 405.2 → 146.0 for ozanimod and m/z 411.1 → 147.05 for ozanimod-D6, used as the internal standard. The total chromatographic run time was 4.5 min, with mass spectrometric data acquisition performed between 2.1 and 3.51 min. The method exhibited linearity over the concentration range of 5 - 600 pg/mL using a weighted (1/C2) linear regression model. The method was validated with respect to selectivity, linearity, accuracy, precision, recovery, matrix effect and stability in accordance with applicable bioanalytical validation principles. The developed method provides a simple and rapid analytical approach for the sensitive quantification of ozanimod in human plasma and is suitable for application in pharmacokinetic and bioequivalence studies.