Separation of ionic drug substances by supercritical fluid chromatography

A Comparative Study of Enantioseparations of Nα-Fmoc Proteinogenic Amino Acids on Quinine-Based Zwitterionic and Anion Exchanger-Type Chiral Stationary Phases under Hydro-Organic Liquid and Subcritical Fluid Chromatographic Conditions

“…A small proportion of a polar additive in the mobile phase is frequently suggested [47,48,49,50] to tune the elution of solutes and to improve peak shapes. Moreover, additives may decrease tailing asymmetry especially during the analyses of basic compounds.…”

A Comparative Study of Enantioseparations of Nα-Fmoc Proteinogenic Amino Acids on Quinine-Based Zwitterionic and Anion Exchanger-Type Chiral Stationary Phases under Hydro-Organic Liquid and Subcritical Fluid Chromatographic Conditions

“…A small proportion of a polar additive in the mobile phase is frequently suggested [47,48,49,50] to tune the elution of solutes and to improve peak shapes. Moreover, additives may decrease tailing asymmetry especially during the analyses of basic compounds.…”

Enantioresolution of dihydropyridine substituted acid by supercritical fluid chromatography on hypercarb® with Z-(L)-arginine as chiral counter ion

“…Even with as low a concentration as 1 mM of the N-blocked amino acid selector in the methanol modifier (20%) sufficiently good selectivity and resolution were obtained. The total actual concentration is then 0.2 mM which is quite low compared to LC systems with N-blocked dipeptides as chiral selectors [14,16] and and the carbon dioxide-based systems mentioned above [19,20]. One can also observe the change in retention with increasing counter ion concentration.…”

Recent developments of enantioseparation techniques for adrenergic drugs using liquid chromatography and capillary electrophoresis: A review

“…Earlier, Pettersson's group [79] used CSA as CMPA for the enantioseparation of ␤-blockers. Then, ZGP and CSA were found to present higher enantioselectivity for chiral separation of ␤-blockers [78,80].…”

A Comparative Study of Enantioseparations of Nα-Fmoc Proteinogenic Amino Acids on Quinine-Based Zwitterionic and Anion Exchanger-Type Chiral Stationary Phases under Hydro-Organic Liquid and Subcritical Fluid Chromatographic Conditions

“…A small proportion of a polar additive in the mobile phase is frequently suggested [47,48,49,50] to tune the elution of solutes and to improve peak shapes. Moreover, additives may decrease tailing asymmetry especially during the analyses of basic compounds.…”

Enantioresolution of dihydropyridine substituted acid by supercritical fluid chromatography on hypercarb® with Z-(L)-arginine as chiral counter ion

“…Even with as low a concentration as 1 mM of the N-blocked amino acid selector in the methanol modifier (20%) sufficiently good selectivity and resolution were obtained. The total actual concentration is then 0.2 mM which is quite low compared to LC systems with N-blocked dipeptides as chiral selectors [14,16] and and the carbon dioxide-based systems mentioned above [19,20]. One can also observe the change in retention with increasing counter ion concentration.…”

Recent developments of enantioseparation techniques for adrenergic drugs using liquid chromatography and capillary electrophoresis: A review

“…Earlier, Pettersson's group [79] used CSA as CMPA for the enantioseparation of ␤-blockers. Then, ZGP and CSA were found to present higher enantioselectivity for chiral separation of ␤-blockers [78,80].…”

A Comparative Study of Enantioseparations of Nα-Fmoc Proteinogenic Amino Acids on Quinine-Based Zwitterionic and Anion Exchanger-Type Chiral Stationary Phases under Hydro-Organic Liquid and Subcritical Fluid Chromatographic Conditions

“…A small proportion of a polar additive in the mobile phase is frequently suggested [47,48,49,50] to tune the elution of solutes and to improve peak shapes. Moreover, additives may decrease tailing asymmetry especially during the analyses of basic compounds.…”

Enantioresolution of dihydropyridine substituted acid by supercritical fluid chromatography on hypercarb® with Z-(L)-arginine as chiral counter ion

“…Even with as low a concentration as 1 mM of the N-blocked amino acid selector in the methanol modifier (20%) sufficiently good selectivity and resolution were obtained. The total actual concentration is then 0.2 mM which is quite low compared to LC systems with N-blocked dipeptides as chiral selectors [14,16] and and the carbon dioxide-based systems mentioned above [19,20]. One can also observe the change in retention with increasing counter ion concentration.…”

Recent developments of enantioseparation techniques for adrenergic drugs using liquid chromatography and capillary electrophoresis: A review

“…Earlier, Pettersson's group [79] used CSA as CMPA for the enantioseparation of ␤-blockers. Then, ZGP and CSA were found to present higher enantioselectivity for chiral separation of ␤-blockers [78,80].…”