Anal. Chem. 1993, 65, 1003-1011
1003
Suppressed Conductometric Capillary Electrophoresis Separation Systems Purnendu K. Dasgupta' and Liyuan Bao Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
A tubular catlon-exchange membrane Is Installed at the end of a 60-cm-long 75-pm-bore fwed-slllca capillary. A static dllute acld regenerant solution surrounds the membrane that functions as a suppressor. With podtlve high voltage applied to the capillary Inlet and the regenerant solution grounded, effectivesuppresdon of electrolytessuch as solutlonsof alkall metal borate, glyclnate, or cyanide Is observed. Electroosmotic flow carrles the capillary effluent past the suppressor Into a conductivity detection cell constitutedby two platinum wlres Inserted through the wall of a poly(v1nyl chloride) capillary. The system provides detectlon limits In the 10-20 pg/L rangefor a variety of anions; a typicalseparation requires 15 mln. Appllcabllity to a variety of real samples Is demonstrated.
Currently capillary electrophoresis (CE) is one of the most active areas in separation science. The basic principles of such separations have been known for some time; the present resurgence of interest is often credited to the work of Mikkers et al.' or more commonly to Jorgenson and Lukacs? whose pioneering studies demonstrated the extremely high separation efficiencies attainable by CE in narrow-bore (
