title: Improved enantioseparation via the twin-column based recycling high performance liquid chromatography.
abstract: A long-neglected recycling high performance liquid chromatography (R-HPLC) strategy was adopted to improve the enantioseparation efficiency in this work. Taking intractable isoxazolidine mixtures as the example, two different R-HPLC methods including single-column and twin-column based strategy were applied to improve the enantioseparation efficiency. Under the optimized conditions, these two methods present distinct separation results: the conceptually simple and commonly used single-column based R-HPLC led to severe peak broadening and degraded separation efficiency; on the contrary, the enantioseparation was significantly improved by adopting the relatively complicated twin-column strategy. This observed difference might be mainly attributed to less peak spreading and sample mixing of the latter, as a result of avoiding redirecting the effluent back to LC pump.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Liu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Junan
authors.initials: J
authors.lastname: Xiao
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Jingang
authors.initials: J
authors.lastname: Yu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Yixi
authors.initials: Y
authors.lastname: Xie
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China; Collaborative Innovation Center of Resource-conserving & Environment-friendly Society and Ecological Civilization, Changsha 410083, China. Electronic address: xqchen@csu.edu.cn.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China. Electronic address: hyangchem@csu.edu.cn.
authors.forename: Hua
authors.initials: H
authors.lastname: Yang
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D013237:Stereoisomerism
keywords: Chiral HPLC; Enantiomeric excess; Enantioseparation; Isoxazolidines; Recycling HPLC; Twin-column based