1,3-dialkylimidazolium-based room-temperature ionic liquids as background electrolyte and coating material in aqueous capillary electrophoresis.
The 1-ethyl-3-methylimidazolium (EMIM) cation was found to have constant mobility of 4.5 x 10(-4) cm2 V(-1) s(-1) over the pH range of 3 to 11. The electroosmotic flow of bare silica capillary was reversed by the covalently bonded room-temperature ionic liquid (RTIL) coating. With run buffer of 5 mM EMIM (pH 8.5), NH4+ in human urine was separated from the K+ matrix and was detected to be 0.37 +/- 0.012%. K+, Na+, Li+, Ca2+, Mg2+ and Ba2+ were baseline separated in RTIL-coated capillary with run buffer of 10 mM EMIMOH-acetic acid at pH 5, and the concentration of the above ions in a red wine were detected to be 907, 27.9, 0, 71.0, 83.4 and 31.1 microg/ml, respectively. The RTIL-coated capillary showed stable electroosmotic flow for at least 80 h in the run buffer.
Qin
Weidong
W
Department of Chemistry, National University of Singapore, Singapore 119260, Singapore.
Weih
Hongping
H
Li
Sam Fong Yau
SF
D004573:Electrolytes / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D007093:Imidazoles / Q000737:chemistry*; D007477:Ions; D008670:Metals / Q000032:analysis; D000644:Quaternary Ammonium Compounds / Q000652:urine; D014920:Wine / Q000032:analysis
D004573:Electrolytes; D007093:Imidazoles; D007477:Ions; D008670:Metals; D000644:Quaternary Ammonium Compounds