@article { ISI:000296830200055, title = {Flow-Through Microvial Facilitating Interface of Capillary Isoelectric Focusing and Electrospray Ionization Mass Spectrometry}, journal = {ANALYTICAL CHEMISTRY}, volume = {83}, number = {22}, year = {2011}, month = {NOV 15}, pages = {8748-8755}, abstract = {A capillary electrophoresis mass spectrometry (CE-MS) interface utilizing a flow-through microvial is used to ensure the electric continuity and supply the catholyte and mobilizer solutions during the capillary isoelectric focusing (cIEF) and mobilization process. The flow-through microvial provides a stable chemical environment and helps to improve the ionization efficiency without significantly diluting the analyte. The CE-MS interface facilitates the transfer of the mobilized cIEF effluent to the site of electrospray ionization, and the gaseous ions can be detected directly by a mass spectrometer. It also allows for complete focusing and mobilization processes to be performed automatically in programmed sequences with commercial CE systems. Two different strategies, using either a part of the capillary or the flow-through microvial of the CE-MS interface as the catholyte reservoir for bare fused silica capillaries or neutral coated capillaries, respectively, were developed for automated cIEF-electrospray ionization (ESI)-MS. Reasonable separation efficiency was achieved using proper concentration of carrier ampholytes and suitable strategies of electroosmotic/electrophoretic mobilization.}, issn = {0003-2700}, doi = {10.1021/ac202130f}, author = {Zhong, Xuefei and Maxwell, E. Jane and Ratnayake, Chitra and Mack, Scott and Chen, David D. Y.} }