title: Surface-imprinted microspheres prepared by a template-oriented method for the chiral separation of amlodipine.
abstract: The surface imprinting technique has been developed to overcome the mass-transfer difficulty, but the utilization ratio of template molecules in the imprinting procedure still remains a challengeable task to be improved. In this work, specifically designed surface-imprinted microspheres were prepared by a template-oriented method for enantioseparation of amlodipine besylate. Submicron mesoporous silica microspheres were surface-modified with double bonds, followed by polymerizing methacrylic acid to generate carboxyl modified mesoporous silica microspheres (PMAA@SiO2). Afterwards, PMAA@SiO2was densely adsorbed with (S)-amlodipine molecules to immobilize template molecules through multiple hydrogen bonding interactions. Then surface molecular imprinting was carried out by cross-linking the carboxyl group of PMAA@SiO2with ethylene glycol diglycidyl ether. The surface-imprinted microspheres showed fast binding kinetics of only 20 min for equilibrium adsorption, and the saturation adsorption capacity reached 137 mg/g. The imprinted materials displayed appreciable chiral separation ability when used as column chromatography for enantioseparation of amlodipine from amlodipine besylate, and the enantiomeric excess of (S)-amlodipine reached 13.8% with only 2.3 cm column length by no extra chiral additives. Besides, the imprinted materials exhibited excellent reusability, and this allows the potential application for amplification production of amlodipine enantiomer.
authors.affiliation: Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, Hunan, China.|School of Chemical Engineering, Xiangtan University, Xiangtan, Hunan, China.
authors.forename: Shenzhi
authors.initials: S
authors.lastname: Lai
authors.affiliation: Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, Hunan, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Ouyang
authors.affiliation: Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, Hunan, China.
authors.forename: Changqun
authors.initials: C
authors.lastname: Cai
authors.affiliation: Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, Hunan, China.
authors.forename: Wensheng
authors.initials: W
authors.lastname: Xu
authors.affiliation: Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, Hunan, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Chen
authors.affiliation: Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, Hunan, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D017311:Amlodipine / Q000302:isolation & purification*; D000959:Antihypertensive Agents / Q000302:isolation & purification*; D008863:Microspheres; D054802:Molecular Imprinting; D011108:Polymers; D012822:Silicon Dioxide
chemical_list: D000959:Antihypertensive Agents; D011108:Polymers; D017311:Amlodipine; D012822:Silicon Dioxide
keywords: amlodipine; enantioseparation; surface-imprinted microsphere; template