Rapid and efficient enantioseparation of ( S )‐amlodipine by surface‐imprinted core–shell polymer microspheres

We present a protocol for the preparation of surface‐imprinted polymer microspheres by core–shell precipitation polymerization for the enantioseparation of ( S )‐amlodipine. In this work, submicron mesoporous silica microspheres were prepared with gemini cationic surfactant as soft template. Molecularly imprinted polymers were coated on the silica supports with a low level of crosslinking, and the thickness of the thin‐walled imprinted shell was about 45 nm. The material showed fast binding kinetics for ( S )‐amlodipine (within only 20 min for complete equilibrium), and the saturation adsorption capacity reached 309.2 mg/g, indicating the good accessibility of binding sites and improved mass transfer for target molecule. The imprinted microspheres exhibited an appreciable enantiomeric excess of ( S )‐amlodipine of 11.3% when used as a glass chromatography column for the enantioseparation of ( S )‐amlodipine from amlodipine besylate without extra chiral additives. The surface‐imprinted materials display potentially amplification for industrial enantioseparation of ( S )‐amlodipine.