Ionic Liquid 1-Vinyl-3-dodecylimidazole Bromide Embedded Hybrid Monolithic Column and Its Versatile Post-modification with Amino Acids

Abstract

The amino acids post-modified ionic liquids-based hybrid monolithic columns were successfully developed. For the first step, using 1-vinyl-3-dodecylimidazole bromide (VDI·Br) and polyhedral oligomeric silsesquioxane methacryl substituted (POSS-MA) as monomer and crosslinking agent, the monolithic POSS-VDI matrix material was polymerized in 100 μm capillary. The prepared POSS-VDI column is of ion-exchange/reverse-phase mixed-mode retention characteristics. The column efficiency reached 137,000 N/m for thioureas. The POSS-VDI column has also been successfully applied to recognize and analyze the effective components of Traditional Chinese Medicines Fangji and the Root of Kudzu Vine. Furthermore, based on its good chromatographic performances, in the second step, amino acids l-Proline (l-Pro), Glycine (Gly) or DL-Phenylalanine (DL-Phe) were further exploited as the anion exchangers to post-modify the POSS-VDI column. The new POSS-VDI-Pro, POSS-VDI-Gly and POSS-VDI-Phe columns exhibited different separation selectivity for the complex egg white protein sample. The present work provides a good route to fabricate versatile amino acids and ionic liquids modified monolithic columns with good separation selectivity.