title: Adsorption behaviour of a quinidine carbamate-based chiral stationary phase: role of the additive.
abstract: In this study, we incorporate the additive properties into the theoretical model of a general preparative chromatographic system; this is normally not done and this limits a proper process optimization. As a model phase system, we used the adsorption of 9H-fluoren-9-ylmethoxycarbonyl-allylglycine (Fmoc-allylglycine) enantiomers on a quinidine carbamate-based chiral stationary phase (anion exchanger) together with a methanol-glacial acetic acid-ammonium acetate eluent. The inverse method was used to measure the competitive adsorption isotherms of both the Fmoc-allylglycine enantiomers as well as the non-detectable additive acetic acid. It was concluded that this enantioselective preparative system is well described by a non-heterogeneous adsorption model and that the loading capacity is very high. The proposed model is valid over a wide range of additive concentrations, which is important for process optimization.
authors.affiliation: AstraZeneca AB, Process R&D, Södertälje, Sweden.
authors.forename: Robert
authors.initials: R
authors.lastname: Arnell
authors.forename: Patrik
authors.initials: P
authors.lastname: Forssén
authors.forename: Torgny
authors.initials: T
authors.lastname: Fornstedt
authors.forename: Roccaldo
authors.initials: R
authors.lastname: Sardella
authors.forename: Michael
authors.initials: M
authors.lastname: Lämmerhofer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lindner
mesh_terms: D019342:Acetic Acid / Q000737:chemistry*; D000327:Adsorption; D002219:Carbamates / Q000737:chemistry*; D003198:Computer Simulation; D011804:Quinolines / Q000737:chemistry*; D015203:Reproducibility of Results; D013237:Stereoisomerism; D013696:Temperature; D013997:Time Factors
chemical_list: D002219:Carbamates; D011804:Quinolines; C508171:quinidine carbamate; D019342:Acetic Acid