Chiral LC–MS/MS method for the discrimination of triiodothyronine enantiomers on a crown ether-based chiral stationary phase

Abstract

Considering the greater pharmaceutical and clinical interest of triiodothyronine (T3) thyroid hormone, an effective D/L-T3 enantiomer separation was performed on a crown ether-based chiral stationary phase by LC–MS/MS. In optimal analytical condition and selected reaction monitoring mode, the two enantiomers of T3 were baseline separated within 10 min. The limit of detection and limit of quantitation were found to be 0.05 and 0.10 ng/μl; 0.20 and 0.50 ng/μl for D- and L-T3, respectively. During validation, this method proved to be feasible, accurate as well as enantioselective and sensitive for the resolution of T3 enantiomers. For commercial D- and L-T3 chemicals, the enantiomeric impurities as the other enantiomer were 0.11% and 4.61%. On the other hand, the impurity as D-T3 for commercial pharmaceutical products (liothyronine sodium tablets, two suppliers) was 0.68% and 6.57%.