LC-MS Compatible Stability Indicating RP-UPLC Method for the Estimation of Ester Prodrug of Mycophenolic Acid in Injection Formulation

Abstract

This study explores the ultra performance liquid chromatography for the quantification of mycophenolate mofetil (an immunosuppressant agent) in an injection formulation. Mycophenolate mofetil was separated from its seven specified impurities on HSS (high strength silica) C18 column (100 × 2.1 mm, 1.8 µm). The optimized mobile phase is compatible to mass spectrometry and hence the method can be equally run on LC-MS system for mass determinations. Efficient UV detection at 250 nm enabled determination of mycophenolate mofetil with no interference from placebo solution, diluent and other specified and unspecified impurities. The retention time of mycophenolate mofetil in the method was 1.79 min and all other impurities were eluted within in 8 min. The method optimization studies show that the selectivity of mycophenolate mofetil and its impurities was dependent on the type of organic solvent and its elution strength. The method was validated for specificity, linearity, precision, accuracy and robustness in range of 50 to 150 % of target analyte concentration (i.e. 62.50-195.31 µg mL -1 ). The linearity of peak area responses versus concentrations was demonstrated by linear least square regression analysis. An excellent linear relation exists between the concentration and detector response (R 2 > 0.9999). Precision of the test method was proved with a relative standard deviation less than 1.0 %.