Suitability of various chromatographic and spectroscopic techniques for analysis and kinetic degradation study of trelagliptin

Multifaceted comparative analytical methods for trelagliptin (TRL) were investigated, applied to ZAFATEK tablets and HPLC-UV was selected for a degradation kinetic study. UPLC-MS/MS (Method I), UPLC-UV (Method II), HPLC-UV (Method III), UHPLC-UV (Method IV) and direct UV (Method V) methods were developed. Methods (I-V) showed satisfactory results using TRL concentration ranges of 50–800 ng/mL, 2.5–80 μg/mL, 5–100 μg/mL, 5–100 μg/mL and 5–50 μg/mL, respectively. Multiple Reaction Monitoring (MRM) of the transition pairs of m/z 358.176 to 134.127 for TRL and m/z 340.18 to 116.08 for alogliptin (IS) were employed utilizing positive mode Electrospray Ionization (ESI). The degradation kinetic study (Method VI) was carried out using 1 N HCl based on three different temperatures (70 °C, 80 °C and 90 °C). Through the optimized method-3, a good chromatographic separation of TRL from its major degradation product was achieved. Arrhenius plot was used in the kinetic study and the apparent 1(st) order degradation rate constant (K), t(1/2), t(90), and the activation energies were calculated for each temperature and at 25 °C. The optimized UPLC-MS/MS method is suitable for further TRL assay either in biological fluids or in the presence of impurities.