Enantiomeric separation of bupropion by liquid chromatography on derivatized cyclofructan chiral stationary phase.

High-performance liquid chromatography (HPLC) is an ideal tool for enantiomeric separations of different drugs. In this study, the direct enantioseparation of bupropion, an atypical antidepressant structurally related to cathinone, was explored by using five chiral columns, including three based on derivatized cyclofructans, macrocyclic glycopeptide teicoplanin, and an immobilized amylose derivative under multimodal elution conditions. Baseline enantioseparation was obtained on the LarihcShell CF6-RN column, with derivatized cyclofructan 6, in the polar organic mode. The effects of the mobile-phase composition, type and content of major components, the nature and the amount of mobile-phase additives, and the column temperature on the retention, selectivity, and resolution were investigated to optimize enantioseparation. The calibration curve was linear in the range of 10-125 µg/ml for each enantiomer. The limits of detection and quantification were 0.1 and 0.3 µg/ml for both enantiomers of bupropion. The chiral recognition was controlled especially by H bonds, π-π, dipole-dipole interactions, and steric effects. Finally, the developed method was applied to the determination of bupropion in the commercially available drug.

Fast enantioseparation of indole phytoalexins in additive free supercritical fluid chromatography.

A series of chiral indole phytoalexins with potential anticancer and antimicrobial activity were enantioseparated in supercritical fluid chromatography. Two polysaccharide-based chiral stationary phases composed of tris-(3,5-dimethylphenylcarbamate) derivatives of amylose or cellulose coated on 2.5 µm silica particles were successfully used. The influences of the polysaccharide backbone, co-solvent type and co-solvent content in the mobile phase on retention, enantioselectivity and enantioresolution of indole phytoalexins were investigated. Fast baseline separations were achieved for 26 from 27 tested compounds. Amylose-based chiral stationary phase provided higher number of baseline resolutions of the indole phytoalexins than the cellulose-based one. However, certain complementary enantioresolution results towards the studied compounds were observed between the investigated columns. The relationship between structure of the indole phytoalexins and their chromatographic behavior in supercritical fluid chromatography was discussed.