Spectrophotometric quantification of direct factor xa inhibitor, rivaroxaban, in raw and tablet dosage form

Two simple spectrophotometric methods (I and II) are described for the determination of rivaroxaban in bulk and tablets. Method I is based on the reaction of rivaroxaban with 4-Chloro-7-nitrobenzo-2-oxa-1,3-diazole in alkaline medium. Method II involved the reaction of rivaroxaban with p-Dimethylaminocinnamaldehyde in acidic medium. The reactions products were measured at 405 nm and 545 nm for methods I and II, respectively. Beer's law was obeyed over the concentration ranges of 2-20 g/mL and 25-125 g/mL with lower limits of detection of 0.110 g/mL and 0.483 g/mL for Methods I and II, respectively. Percent recovery of rivaroxaban for both methods I and II were found in the range of 99.74-100.51% with relative standard deviation in the range of 0.621-0.900%. The proposed methods I and II were successfully applied for quantification of rivaroxaban in tablet dosage forms with good accuracy and precision. Hence, the proposed methods I and II can be suitably adopted for routine analysis of rivaraxaban.