Functionalized metal-organic framework nanocomposites for dispersive solid phase extraction and enantioselective capture of chiral drug intermediates.

The facile preparation, characterization and application of a novel magnetic graphene oxide- metal organic framework [Zn(d-Cam)(4, 4'-bpy)] (MGO-ZnCB) as a sorbent for fast, simple and enantioselective capture of chiral drug intermediates are presented in this paper. The MGO-ZnCB nanocomposite, developed by encapsulating MGO nanoparticles into the homochiral metal organic framework of ZnCB, can integrate the advantages from each component endowing the hybrids with improved synergystic effects. The enantioselective performance of MGO-ZnCB was evaluated by dispersive magnetic nanoparticle solid phase extraction (d-MNSPE) of 1, 1'-bi-2-naphthol (BN) and 2, 2'-furoin (Furoin) racemic solutions. Due to the excellent dispersive capability, high stability, relatively larger saturation magnetization and distinct enrichment capacity of MGO-ZnCB, the d-MNSPE method provids good enantioselective separation of these compounds with enantiomeric excess (ee) values as high as 74.8% and 57.4%, respectively. The entire process with BN or Furoin can be completed within 3 min or less. After washing with methanol, the host MGO-ZnCB can be easily recycled and reused six times without any apparent loss of performance. Furthermore, the adsorbed BN and Furoin in nanodomains of the MGO-ZnCB composite were directly investigated for the first time by atomic force microscopy-infrared (AFM-IR) technique.