Determination of irsogladine using HPLC-ESI-MS/MS in human plasma: Application to bioequivalence study

A highly sensitive analytical tool for the fast quantification of irsogladine in human plasma was developed. Cleanup using a solid-phase extraction technique is a simple method for extracting both irsogladine and lamotrigine (internal standard) spiked into human plasma: 89.4 ± 2.4% for irsogladine and 85.9 ± 3.4% for lamotrigine. The resolvable separation of both analytes through reversed-phase high-performance liquid chromatography (HPLC) was carried out within 5 min. The HPLC-electrospray ionization (ESI)-tandem mass spectrometry (MS) method, which was operated in a selected reaction monitoring mode specific to the target analytes, was verified for use in the quantification of irsogladine. The inter- and intra-day precision (RSD) were <4% and their accuracies were between 85.9 to 89.8%. The calibration curve for irsogladine spiked into human plasma was linear over the range from 1 to 100 ng/mL; the limit of quantification was estimated to be 1.8 ng/mL. The established method was successfully applied for a bioequivalence study of irsogladine.