LC Method for Determination of Rasagiline Mesylate in Different Plasma Matrices and its Application to Oral Pharmacokinetic Study in Rabbits

A simple, rapid and sensitive reverse-phase liquid chromatographic method is developed and validated for estimation of rasagiline mesylate in different plasma matrices (rat, rabbit and human plasma). The method employs an isocratic elution technique with a Kromasil C18 column and has an optimized mobile phase composition of 10 mM ammonium acetate buffer-acetonitrile (40:60 v/v). The plasma samples displayed linear detector responses in the concentration range of 0.5-20 µg/mL in all plasma matrices when monitored at 265 nm using an ultraviolet detector. Because the simple protein precipitation method yields over 95% recovery of rasagiline mesylate from all plasma matrices, no internal standard was used in this method. A detailed validation study of the method proves the accuracy, precision and selectivity (in estimating rasagiline mesylate) in all plasma matrices. The drug is also stable under various processing and storage conditions in all plasma matrices, as evident from the study. The present method was applied to determine the drug-protein binding ratio in all the plasma matrices. The use of this method in determining pharmacokinetic parameters of rasagiline mesylate by non-compartmental analysis after oral dosing in rabbits is also discussed.