Novel approach for fritless capillary electrochromatography

作者：Baltussen E; van Dedem GWK^*

来源：Electrophoresis, 2002, 23(9): 1224-1229.

DOI：10.1002/1522-2683(200205)23:9<1224::AID-ELPS1224>3.0.CO;2-S

• capillary column packing
• capillary electrochromatography

At present, the main limitation for the further adoption of capillary electrochromatography (CEC) in the (routine) laboratory is caused by the lack of reproducible and stable columns. The main source of column instability is concentrated in the frits needed to retain the packed bed inside the CEC capillary. The sintering process used to prepare the frits can be rather problematic and irreproducible, particularly for small stationary phase particles and wide column diameters. Since the (surface) composition of the frits is different from the bulk stationary phase packing, different electroosmotic flow (EOF) velocities are generated. This effect is assumed to be primarily responsible for rapid column destruction. In this contribution, a novel approach for the preparation of fritless CEC capillaries is presented and evaluated. Using 5 pm Hypersil ODS particles, separation efficiencies in the range of 130000-200000 plates/m were obtained. In a 100 mum inner diameter packed column, electrical currents up to 50 muA could be tolerated without negative effects such as bubble formation. The prepared CEC columns were found to be stable and could easily be operated continuously for several days without column damage. An additional advantage of the proposed tapering approach is that application of pressure on the in- and outlet vial during separation was not required to prevent bubble formation.

• 出版日期2002-5