γ-Cyclodextrin metal-organic framework supported by polydopamine as stationary phases for electrochromatographic enantioseparation

• Published in: Talanta (Oxford) 2020-10, Vol.218, p.121160-121160, Article 121160
• Main Authors: Li, Zhentao, Mao, Zhenkun, Zhou, Wei, Chen, Zilin
• Format: Article
• Language: English
• Subjects: Chiral stationary phase; Dns-DL-amino acids; Electrochromatography; Enantioseparation; Open-tubular column; γ-CD-MOF
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2020.121160

Metal-organic frameworks (MOFs) are a novel class of porous nanomaterials composed of metals and organic linkers that have been used in many fields. A novel stereoselective stationary phase for capillary electrochromatography (CEC) has been developed in this work by employing a biodegradable, easier-to-prepare and green homochiral MOFs (Cu-SD), which composed of octakis-[6-deoxy-6-(3-mercaptopropanoic sodium)]-γ-cyclodextrin (SD, sugammadex) and transition metal ion (Cu2+) supported by polydopamine as linker. The modified capillary was characterized by scanning electron microscopy (SEM), X-ray spectrometry (XRD), energy dispersive (EDS) and Fourier transform infrared spectroscopy (FT-IR). The Cu-SD modified capillary column exhibited outstanding chiral recognition separation for five Dns-DL-amino acids (the DL-forms of phenylalanine, leucine, valine, threonine, serine). In addition, the modified column showed excellent stability and reproducibility. The relative standard deviations (RSDs) of the retention time for intra-day (n = 5) and inter-day (n = 3) and between columns (n = 3) enantioseparations were less than 0.27, 1.45 and 4.88%, respectively. Conceivably, this new-type of γ-CD-MOF represents a useful chiral stationary phase in electrochromatographic separations, and it has great potential in chiral separation field. [Display omitted] •The combination of host-guest cavity and coordination sites makes Cu-SD fit for enantioseparation.•The polydopamine-supported method for immobilization of Cu-SD was simple and efficient.•The Cu-SD@PD@capillary exhibited good enantioseparation selectivity for Dansyl-DL-amino acids.•The Cu-SD@PD@capillary showed excellent reproducibility and stability.