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

Considering the greater pharmaceutical and clinical interest of triiodothyronine (T 3 ) thyroid hormone, an effective D/L-T 3 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 T 3 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-T 3 , respectively. During validation, this method proved to be feasible, accurate as well as enantioselective and sensitive for the resolution of T 3 enantiomers. For commercial D- and L-T 3 chemicals, the enantiomeric impurities as the other enantiomer were 0.11% and 4.61%. On the other hand, the impurity as D-T 3 for commercial pharmaceutical products (liothyronine sodium tablets, two suppliers) was 0.68% and 6.57%.