Advances in the enantioseparation of second-generation antidepressant drugs by electrodriven methods

Stereochemistry is steadily increasing in importance in the development of new drugs, and the availability of pure enantiomer drugs can make therapy safer and more efficacious. In particular, almost all second generation antidepressant drugs possess one or more chiral centers; however, only some of them are administered as single enantiomers. A fundamental part of the quality control of pharmaceutical formulations is the determination of enantiomeric excess and enantiomeric purity; this is also important for the therapeutic drug monitoring of depressed patients. For this purpose, efficient and reliable analytical methods are needed and electrodriven techniques (most of all capillary electrophoresis, capillary electrochromatography and micellar electrokinetic chromatography) are very efficient and inexpensive candidates for the role. In this review, the enantioselective electrodriven methods available for the analysis of second generation antidepressant are presented and discussed. In particular, the following pharmacological classes of antidepressants will be considered: selective serotonin reuptake inhibitors (SSRIs: fluoxetine, citalopram, paroxetine, sertraline); norepinephrine reuptake inhibitors (NRIs: reboxetine); serotonin and norepinephrine reuptake inhibitors (SNRIs: venlafaxine, milnacipran, duloxetine); and noradrenergic and specific serotonergic antidepressants (NaSSAs: mirtazapine).