Determination of zolmitriptan enantiomers in rat liver microsomes by chiral high performance liquid chromatography with ?uorescence detection

Abstract

A selective chiral high performance liquid chromatographic method was developed and validated to separate and quantify the enantiomers of a new potent selective 5-HT(1B/1D) receptor partial agonist, S-zolmitriptan, and its antipode in rat liver microsomes induced with beta-naphtho flavone. S- and R-zolmitriptan were extracted from rat hepatic microsomal incubates with chloroform/isopropanol (75:25, v/v), and were separated on a narrow-bore enantioselective normal phase Chiralpak AD-H column (250 x 0.46 mm) with hexane-isopropanol-triethylamine (72/28/0.25, v/v/v) as mobile phase and fluorescence detection with emission at 350 nm and excitation at 291 nm. The calibration curves were linear for R- and S-zolmitriptan concentration over the range 0.1-5.0 microg/mL (r = 0.9996 and 0.9999), and the limits of quantitation were 0.1 microg/mL. The metabolism and interaction of the enantiomers of zolmitriptan in treated hepatic microsomes were investigated using chiral HPLC. There was significant difference between the disposition of the S- and R-zolmitriptan when racemic zolmitriptan or single enantiomers of zolmitriptan were incubated for 5, 10 and 20 min, suggesting that the metabolism of zolmitriptan in rat liver microsomes is enantioselective. In addition, there was also a significant difference between the IC(50) of R- to S-zolmitriptan and S- to R-zolmitriptan (IC(50S/R)/IC(50R/S) = 45.2). This indicated that the disposition process favored the S-form of zolmitriptan.

Significance and challenges of stereoselectivity assessing methods in drug metabolism

“…This method is easy, reliable, and can be applied to the simultaneous quantitative analysis of drug enantiomers in other clinical samples. Yu et al [54] developed a method to separate and quantify the enantiomers of a new potent selective 5-HT1B/1D receptor partial agonist, (S)-zolmitriptan, and its antipode in rat liver microsomes using a narrow-bore enantioselective normal phase Chiralpak AD-H column (250 mm×0.46 mm) with hexane–isopropanol–triethylamine as mobile phase and fluorescence detection. However, it should be noted that we should not use the eluents containing hydrochloric ethers, which will strip cellulose from the surface of silicon.…”

Validated RP-HPLC Method for the Determination of Zolmitriptan - A Serotonin 5-HT Receptor Agonist

“…Srinivasu developed liquid chromatographic method for its enantiomereic separation as well as its potential impurities [8,9]. Yu et al [10] and Chen [11] determined zolmitriptan enantiomers in rat liver microsomes by chiral high performance liquid chromatography with fluorescence detection. Hu et al [12] and Vijayakumar et al [13] determined ZLM and its related substances.…”

The successful binomium of multivariate strategies and electrophoresis for the Quality by Design separation of a class of drugs: the case of triptans

“…CE has been used for the analysis of TRP as single drugs such as sumatriptan and naratriptan , in stability indicating methods based on MEKC for sumatriptan , and MEEKC for rizatriptan and almotriptan . Enantioseparation of frovatriptan and zolmitriptan has been performed by EKC consisting of a plain buffer with addition of cyclodextrins.…”