caa a22 4500 445881550 CHVBK 20180317145545.0 cr unu---uuuuu 170323e20110701xx s 000 0 eng 10.1007/s00604-011-0599-y doi (NATIONALLICENCE)springer-10.1007/s00604-011-0599-y Electrophoretic separation of acidic and basic proteins in the presence of micromolar concentrations of an ionic liquid [Elektronische Daten] [Janar Tursen, Aimin Wang, Weidong Qin] We report on the use of an ionic-liquid (IL) as additive to an acidic background electrolyte (BGE) for capillary electrophoretic separation of the proteins human serum albumin, transferrin, trypsin inhibitor, hemoglobin, catalase, myoglobin and lysozyme. The method was carried out in a capillary zone electrophoresis mode because the concentration of the ionic liquid is far below its critical micelle concentration, and the proteins were detected by measurement of capacitively coupled contactless conductivity. The addition of the IL to the BGE in micromolar concentration improves (a) the detection sensitivity of the method, (b) the recovery of the protein due to the alleviated wall-adsorption of proteins, and (c) the resolution due to strong interaction between IL and protein. In fact, even microheterogeneous variants of trypsin inhibitor, hemoglobin and catalase could be resolved. Proteins were separated within typically 18min at pH 2.5, with detection limits of 0.7 to 9.4μg mL−1 (34.8-141.1 nM). The method was specifically employed to analyze human serum samples. Figure Model proteins, lysozyme (1), human serum albumin (2), transferrin (3), myoglobin (4), trypsin inhibitor (5), hemoglobin (6) and catalase (7), partially merged in 200mM HAc (a); but they were better resolved in the presence of 30μM [C12MIm]Br (b). Springer-Verlag, 2011 Additive nationallicence Background electrolyte nationallicence Contactless conductivity detection nationallicence 1-Dodecyl-3-methylimidazolium-bromide ionic liquid nationallicence Protein nationallicence Human serum nationallicence Tursen Janar College of Chemistry, Beijing Normal University, No. 19, Xinjiekou Wai Street, 100875, Beijing, People's Republic of China aut Wang Aimin College of Chemistry, Beijing Normal University, No. 19, Xinjiekou Wai Street, 100875, Beijing, People's Republic of China aut Qin Weidong College of Chemistry, Beijing Normal University, No. 19, Xinjiekou Wai Street, 100875, Beijing, People's Republic of China aut Microchimica Acta Springer Vienna 174/1-2(2011-07-01), 63-71 0026-3672 174:1-2<63 2011 174 604 https://doi.org/10.1007/s00604-011-0599-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00604-011-0599-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tursen Janar College of Chemistry, Beijing Normal University, No. 19, Xinjiekou Wai Street, 100875, Beijing, People's Republic of China aut NATIONALLICENCE 700 1- Wang Aimin College of Chemistry, Beijing Normal University, No. 19, Xinjiekou Wai Street, 100875, Beijing, People's Republic of China aut NATIONALLICENCE 700 1- Qin Weidong College of Chemistry, Beijing Normal University, No. 19, Xinjiekou Wai Street, 100875, Beijing, People's Republic of China aut NATIONALLICENCE 773 0- Microchimica Acta Springer Vienna 174/1-2(2011-07-01), 63-71 0026-3672 174:1-2<63 2011 174 604 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer