In situ rapid preparation of homochiral metal-organic framework coated column for open tubular capillary electrochromatography

• A novel homochiral metal organic framework coated capillary column was developed.
• The coating was in situ synthesized in 1 h by using ZnO as nucleating agents.
• Well enantioseparation of three monoamine neurotransmitters was achieved.
• The isomers of nitrophenols and analogues of bisphenols were also well separated.

Fabricating metal-organic frameworks (MOFs) with the use of nucleating agents in the microenvironment have attracted increasing attention recently. Herein, a simple and rapid synthesis method was developed to in situ fabricate homochiral MOF [Zn(s-nip)2]n in the capillary inner wall by using ZnO nanoparticles as efficient nucleating agents for open tubular capillary electrochromatography (OT-CEC) separation of monoamine neurotransmitters enantiomers of epinephrine, isoprenaline and synephrine, the diastereoisomers of ephedrine and pseudoephedrine, the isomers of nitrophenols and analogues of bisphenols with good resolution. The relative standard deviations (RSDs) for the analytes migration time of intra-day, inter-day and column-to-column were in the range of 0.8–2.1% (n = 10), 0.3–3.2% (n = 3) and 3.2–9.3% (n = 3), respectively. Additionally, the homochiral MOF [Zn(s-nip)2]n coated capillary column could be successively used over 260 runs without observable change in the separation efficiency.