Determination of vitamin K1 in blood serum by high-performance liquid chromatography

A method is proposed for the determination of vitamin K1 concentration in blood serum using HPLC on a Gemini C18 (250 mm × 4.6 mm ID, 5 μm) column and elution with a methanol–acetonitrile–dichloromethane (45 : 50 : 5, v/v) mobile phase at a flow rate of 1 mL/min and detection at 248 nm. The limit of detection for the vitamin is 0.5 ng/mL and relative error is 19%. The volume of sample in the column is 100 μL. The method has been applied to the evaluation of vitamin K1 deficit in a human body in medical practice.