Hydrophilic interaction liquid chromatography for separation and quantification of selected room-temperature ionic liquids.

CEA Saclay, DEN/DANS/DPC/SECR/LSRM, 91191, Gif-sur-Yvette, France.
Journal of Chromatography A (Impact Factor: 4.61). 10/2007; 1164(1-2):139-44. DOI: 10.1016/j.chroma.2007.06.053
Source: PubMed

ABSTRACT Hydrophilic interaction liquid chromatography (HILIC) is an alternative technique to ion pairing-reversed-phase liquid chromatography (IP-RPLC) and classical RPLC for separation of alkylimidazolium room-temperature ionic liquids (RTILs). Particularly, HILIC offers better retention and selectivity for short-chains RTILs imidazolium compounds. HILIC mechanisms were investigated by studying the influence of organic modifier content and salt concentration in the mobile phase. HILIC method was validated by quantifying 1-butyl-3-methylimidazolium cation (BMIM) degradation under gamma radiation at 2.5MGy. Development of separative reproducible analytical methods, including for low concentration, applicable to RTILs are today mandatory to improve RTILs chemistry.

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