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Indexed by:期刊论文

Date of Publication:2016-10-01

Journal:CHROMATOGRAPHIA

Included Journals:SCIE、Scopus

Volume:79

Issue:19-20

Page Number:1263-1269

ISSN No.:0009-5893

Key Words:Monolithic column; Ring-opening polymerization; Anion exchange; Capillary liquid chromatography; POSS

Abstract:Polyethylenimine (PEI) and 2,4,6,8-tetramethyl-2,4,6,8-tetrakis(propyl glycidyl ether) cyclotetrasiloxane (POSS-epoxy) were used as precursors for the preparation of organic-silica hybrid monolithic columns (PEI-POSS monolith) via epoxy-amine ring-opening polymerization (ROP). The high density of amine groups in PEI provides rich chromatographic interaction sites for the polar or acidic analytes in hydrophilic interaction (HILIC) and weak anion exchange (WAX) mechanisms. The column preparation conditions, such as the porogens, solvent and reaction temperature, were systematically investigated according to the morphology, permeability and column efficiency. The separation mechanisms of HILIC and WAX were evaluated with neutral polar compounds and halogen benzoic acids. Owing to the existence of reactive amine groups on the matrix surface, the PEI-POSS monolith is also an ideal starting material for the preparation of HILIC or strong anionic exchange (SAX) stationary phases by modification. The modification of PEI-POSS monoliths with iodomethane or bromoacetic acid via the nucleophilic substitution reaction could achieve the retention mechanisms of SAX or zwitterionic HILIC, respectively.