Chromatographic separation of tiropramide hydrochloride and its degradation products along with their structural characterization using LC-QTOF-MS/MS and NMR.

Tiropramide HCl, an antispasmodic drug was subjected to various stress conditions (hydrolytic, oxidative, photolytic and thermal) as per ICH guidelines. The drug is widely used as an antispasmodic agent but there were no comprehensive degradation studies reported on it. Hence, forced degradation studies of tiropramide HCl were carried out to establish the degradation profile and the storage conditions to maintain its quality attributes during the shelf life and usage. A selective HPLC method was developed to separate the drug as well as its degradation products using Agilent C18 (250×4.6 mm; 5 μm) column. The mobile phase of 10mM ammonium formate at pH 3.6 (solvent A) and methanol (solvent B) with gradient elution at a flow rate of 1.00 mL/min was used. Tiropramide was susceptible to acidic, basic hydrolytic exposure and oxidative stress conditions in the solution. This drug was found to be stable in neutral, thermal and photolytic conditions in both solution and solid-state. Five degradation products were detected under different stress conditions. The mass spectrometric fragmentation pattern of tiropramide and its degradation products was extensively studied using LC-Q-TOF-MS/MS for their structural characterization. The position of the oxygen atom in the N-oxide degradation product was confirmed by NMR studies. The knowledge gained by these studies was used to predict drug degradation profiles which will be helpful in analysing any impurities in dosage form.