A novel cross-linked co-polymeric ionic liquid as a potential adsorbent for highly efficient adsorption of curcuminoids

Abstract

A novel cross-linked co-polymeric ionic liquid is prepared via mini-emulsion polymerization by using N-vinyl-3-(2-methoxy-2-oxyl ethyl) imidazolium chloride as a monomer and 1,4-butanediyl-3,3′-bis-l-vinylimidazoliurn dibromide as a crosslinker. The as-synthesized material is used as an adsorbent for the solid-phase extraction of curcuminoids. Ion-exchange and hydrogen-bonding interactions contribute to a highly efficient adsorption of curcuminoids onto the cross-linked co-polymeric ionic liquid, and a maximum adsorption capacity of 108.7 μg mg⁻¹ is achieved. Both the adsorption and desorption of curcuminoids could be achieved within 15 s, giving rise to a fast extraction process. This developed extraction protocol is applied to the isolation of curcuminoids from Curcuma longa Linn, and HPLC analysis demonstrates obvious improvement in extraction efficiency as compared with conventional extraction methodologies.