BIOANALYTICAL METHOD DEVELOPMENT AND VALIDATION OF MARALIXIBAT IN RAT PLASMA BY LC-MS/MS DETECTION AND ITS APPLICATION TO A PHARMACOKINETIC STUDY

Abstract

Objective: To quantify maralixibat in rat plasma utilizing liquid-liquid extraction (LLE) approach, a practical, efficient, and accurate LC-MS/MS approach was devised. Methods: As an internal standard (IS), Elobixibat was adopted. Utilizing an Agilent eclipse C18, 150 mm x 4.6 mm, 3.5 µm column, the drug separation was accomplished using an isocratic mobile phase entailing acetonitrile (ACN) and buffer (1 ml Tri fluoro acetic acid into 1liter water and stir well. Filtered through 0.22µ membrane filter paper) composition of 70:30 (v/v), dispensed at 1.0 ml/min. Results: Multiple reaction monitoring (MRM) positive mode allowed for the simultaneous detection of maralixibat and elobixibat exhibiting proton adducts around m/z 676.0278-290.3625 and m/z 696.8541-480.6328, correspondingly. The correlation coefficient (r2) of the approach was ≥0.99977 across a linearity concentration spanning between 5.00–100.00 ng/ml. This technique achieved intra-day accuracy and precision between 99.31-100.93% and 0.22-6.55%, correspondingly. Across 3 freeze-thaw sessions, bench top testings, and postoperative stability investigations, maralixibat was shown to be stable. Conclusion: Through intravenous injection, this approach was effectively utilized in rats for studying the drug's pharmacokinetics.