ONLINE MEASUREMENT OF ELECTROOSMOSIS IN CAPILLARY ELECTROPHORESIS USING A CONDUCTIVITY CELL

A common phenomenon in capillary electrophoresis is electroendosmotic dow (EOF). Although often useful, EOF fluctuations introduce extra variances in the overall reproducibility of the analysis. In order to correct for these fluctuations, an on-line EOF monitoring method is required. The method presented utilizes a conductivity cell as the ground electrolyte reservoir, filled with dilute running buffer. During the separation the EOF will cause a continuous dow of non-diluted buffer into this reservoir. From the resulting continuously rising conductivity signal, the EOF can be calculated and used for, e.g., migration time and peak area corrections.