A simple and sensitive HILIC-based UHPLC-MS/MS method for quantifying of rivaroxaban in dried blood spots: Application in comparison with the plasma sample method.

Rivaroxaban, indicated for the treatment of atrial fibrillation, deep vein thrombosis, pulmonary embolism, and coronary or peripheral artery disease, is one of the most frequently used direct oral anticoagulants. Therapeutic drug monitoring [TDM] is essential to minimize bleeding and thrombosis during personalized rivaroxaban treatment. An efficient and reliable analytical technique is required to quatify the rivaroxaban during its therapeutic indication. Dried blood spots (DBSs) sampling is a convenient bioanalytical method with minimal invasive blood drawing, long-term stability, and low shipment and storage costs. Therfore, DBS sampling technique is growing rapidly for TDM of drugs in medical care. This study developed an ultra high performance liquid chromatography-tandem mass spectrometry method of quantitating rivaroxaban in DBSs samples using the isotopic labeled analog (rivaroxaban-d4) as an internal standard (IS). Rivaroxaban and IS were separated on an Acquity HILIC column and eluted with a mobile-phase composition of acetonitrile and 20 mM ammonium acetate in the ratio of 95:5 at a flow rate of 0.3 mL/min. The precursor-to-product ion transitions of 436.03 ˃ 144.9 for rivaroxaban and 440.04 ˃ 144.9 for IS were used to quantify in multiple reaction monitoring mode. The method was accurate and precise in the 2.06-1000 ng/mL calibration range without hematocrit and blood spot volume effects. Rivaroxaban was stable in DBSs samples under different anticipated storage and temperature conditions. We observed good correlation between the plasma concentration and the DBSs concentration, indicating that the proposed DBSs method is suitable for monitoring the rivaroxaban concentration using a simple and convenient sample collection procedure.