Separation of peptides utilizing ultrahigh-temperature micellar electrokinetic chromatography

The use of ultrahigh column temperatures, up to 110 degreesC, in micellar e lectrokinetic capillary chromatography was investigated. The number of plat es generated per unit time increased from 0.22 to 12.8 plates/s for separat ions at 15 degreesC and 110 degreesC, respectively. Ultrahigh-temperature m icellar electrokinetic capillary chromatography was used for the separation of cyclic undecapeptides (cyclosporins). A minimum resolution of 1.39 was calculated for a critical peak pair at 110 degreesC, which is more than a 5 0% increase over resolution generated at 40 degreesC. During a run time of more than 90 min at 110 degreesC and at pH 9.3, no sample degradation or so lvent boiling was observed.