The plasma concentration of atorvastatin was measured by ultra-performance liquid chromatography (ACQUITY UPLC I-CLASS System; Waters, Milford, MA, USA) coupled with tandem mass spectrometry (Xevo TQ-XS triple quadrupole MS/MS system; Waters, Milford, MA, USA). The samples were separated under an ACQUITY UPLC BEH C18, 1.7 μm column (2.1 mm × 50 mm) (Waters, Milford, MA, USA). Atorvastatin-d5 was used as an internal standard (IS). The mobile phase was 10 mM ammonium formate (0.1% formic acid): acetonitrile 45:55 (v/v), with a flow rate of 0.35 mL/min. For the quality control samples, the accuracy was 98.7–100.3%, and the precision was ≤ 2.7%.
Plasma concentrations of EPA and DHA were measured by ultra-performance liquid chromatography (ACQUITY UPLC I-CLASS System; Waters, Milford, MA, USA) coupled with tandem mass spectrometry (Xevo TQ-XS triple quadrupole MS/MS system; Waters, Milford, MA, USA). The samples were separated under a Kinetex C18 100A 1.7 μm column (2.1 mm × 50 mm) (Phenomenex, Torrance, CA, USA). The mobile phase was 5 mM ammonium formate (0.2% formic acid): acetonitrile 30:70 (v/v) and had a flow rate of 0.4 mL/min. For the quality control samples of EPA and DHA, the accuracy was 100.1–104.0% and 100.2–102.1%, respectively, and the precision was ≤ 4.1% and ≤ 4.5%, respectively.
Plasma concentrations of EPA and DHA were measured by ultra-performance liquid chromatography (ACQUITY UPLC I-CLASS System; Waters, Milford, MA, USA) coupled with tandem mass spectrometry (Xevo TQ-XS triple quadrupole MS/MS system; Waters, Milford, MA, USA). The samples were separated under a Kinetex C18 100A 1.7 μm column (2.1 mm × 50 mm) (Phenomenex, Torrance, CA, USA). The mobile phase was 5 mM ammonium formate (0.2% formic acid): acetonitrile 30:70 (v/v) and had a flow rate of 0.4 mL/min. For the quality control samples of EPA and DHA, the accuracy was 100.1–104.0% and 100.2–102.1%, respectively, and the precision was ≤ 4.1% and ≤ 4.5%, respectively.