title: Histidine-modified organic-silica hybrid monolithic column for mixed-mode per aqueous and ion-exchange capillary electrochromatography.
abstract: A novel organic-silica hybrid monolith was prepared through the binding of histidine onto the surface of monolithic matrix for mixed-mode per aqueous and ion-exchange capillary electrochromatography. The imidazolium and amino groups on the surface of the monolithic stationary phase were used to generate an anodic electro-osmotic flow as well as to provide electrostatic interaction sites for the charged compounds at low pH. Typical per aqueous chromatographic behavior was observed in water-rich mobile phases. Various polar and hydrophilic analytes were selected to evaluate the characteristics and chromatographic performance of the obtained monolith. Under per aqueous conditions, the mixed-mode mechanism of hydrophobic and ion-exchange interactions was observed and the resultant monolithic column proved to be very versatile for the efficient separations of these polar and hydrophilic compounds (including amides, nucleosides and nucleotide bases, benzoic acid derivatives, and amino acids) in highly aqueous mobile phases. The successful applications suggested that the histidine-modified organic-silica hybrid monolithic column could offer a wide range of retention behaviors and flexible selectivities toward polar and hydrophilic compounds.
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources, CAS and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.|University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Tang
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources, CAS and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.
authors.forename: Shujuan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources, CAS and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Liang
authors.affiliation: Key Laboratory of Oil & Gas Production, China National Petroleum Corporation (CNPC) and Research Institute of Petroleum Exploration and Development (RIPED), Beijing, China.
authors.forename: Xiaofen
authors.initials: X
authors.lastname: Tang
authors.affiliation: Key Laboratory of Oil & Gas Production, China National Petroleum Corporation (CNPC) and Research Institute of Petroleum Exploration and Development (RIPED), Beijing, China.
authors.forename: Xingcai
authors.initials: X
authors.lastname: Wu
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources, CAS and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources, CAS and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Chemistry of Northwestern Plant Resources, CAS and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.
authors.forename: Shengxiang
authors.initials: S
authors.lastname: Jiang
keywords: Capillary electrochromatography; Ion-exchange chromatography; Mixed-mode chromatography; Organic-silica hybrid monolith; Per aqueous chromatography