Preparation and evaluation of a triazole‐bridged bis(β‐cyclodextrin)–bonded chiral stationary phase for HPLC

Abstract A triazole‐bridged bis(β‐cyclodextrin) was synthesized via a high‐yield Click Chemistry reaction between 6‐azido‐β‐cyclodextrin and 6‐propynylamino‐β‐cyclodextrin, and then it was bonded onto ordered silica gel SBA‐15 to obtain a novel triazole‐bridged bis(β‐cyclodextrin)–bonded chiral stationary phase (TBCDP). The structures of the bridged cyclodextrin and TBCDP were characterized by the infrared spectroscopy, mass spectrometry, elemental analysis, and thermogravimetric analysis. The chiral performance of TBCDP was evaluated by using chiral pesticides and drugs as probes including triazoles, flavanones, dansyl amino acids and β‐blockers. Some effects of the composition in mobile phase and pH value on the enantioseparations were investigated in different modes. The nine triazoles, eight flavanones, and eight dansyl amino acids were successfully resolved on TBCDP under the reversed phase with the resolutions of hexaconazole, 2′‐hydroxyflavanone, and dansyl‐DL‐tyrosine, which were 2.49, 5.40, and 3.25 within 30 minutes, respectively. The ten β‐blockers were also separated under the polar organic mode with the resolution of arotinolol reached 1.71. Some related separation mechanisms were discussed preliminary. Compared with the native cyclodextrin stationary phase (CDSP), TBCDP has higher enantioselectivity to separate more analytes, which benefited from the synergistic inclusion ability of the two adjacent cavities and bridging linker of TBCDP, thereby enabling it a promising prospect in chiral drugs and food analysis.