Improved resolution of tryptic digest fragments from haemoglobin variants using phytic acid in free zone capillary electrophoresis.

Capillary electrophoresis can be applied to the rapid characterization of tryptic digests of proteins. The addition of phytic acid to the separation buffer was found to improve resolution considerably when the technique was applied to differentiate between tryptic digests derived from variant haemoglobins. Moreover, analysis time was of the order of 15 min, which is considerably shorter than that obtained using gradient reversed-phase high-performance liquid chromatography or two-dimensional paper chromatography-electrophoresis.