ELECTRICALLY DRIVEN OPEN-TUBULAR LIQUID-CHROMATOGRAPHY

Electrically driven (ED), as opposed to pressure-driven (PD), open-tubular liquid chromatography (OTLC) was evaluated for different types of open-tubular columns, with inner diameters in the range 5-25 μm. The efficiency of ED-OTLC was found to be better than that of PD-OTLC by a factor of ca. 2, in agreement with theory. Injection of the sample in ED-OTLC by electromigration appears to be much simpler than that with the split-injection procedures in PD-OTLC. Electroosmotic mobility was found to depend little on the application of an ODS coating.With the mobile phase used at 60 000 V/m, the maximum linear velocity was 1.4 mm/s. The potential of ED-OTLC in 10-25 μm I.D. capillaries is demonstrated. © 1990.