Development and Validation of Tetrahydrozoline Hydrochloride in Rat’s Urine using Reverse-Phase HighPerformance Liquid Chromatography

Objective: This study aimed to develop and validate a bioanalytical method to determine tetrahydrozoline hydrochloride in rat’s urine using reverse-phase high-performance liquid chromatography (RP-HPLC) with a UVVis detector. Methods: The RP-HPLC method was developed using an Inertsil? ODS-3 5µm column (4.6 x 150 mm), with a mobile phase of water:methanol:2% formic acid in water (60:30:10), at a flow rate of 1.0 mL/min and was detected at a wavelength of 265 nm. Sample preparation was done using liquid-liquid extraction with acetonitrile: methylene chloride (1:1). The supernatant residue was dried and reconstituted with 500 µL of the mobile phase. Results: The development and validation of the bioanalytical method for tetrahydrozoline hydrochloride fulfilled the requirements of the EMA Guidelines 2011. The results showed the concentration range of the calibration curve was from 5 to 100 µg/mL, with linearity r > 0.9988. Conclusion: The method was successfully applied to a rat's urine sample of tetrahydrozoline hydrochloride with levels in the range of the test.