Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/210513

Title

Salt effects in capillary zone electrophoresis IV: resolution versus time and the effect of potassium phosphate and its concentration in the high ionic strength separation of sulphonamides

Author(s)

Cross, Reginald F.;  Cao, Jing

Abstract

The effects of potassium phosphate buffer and its concentration upon the capillary zone electrophoretic separation of 23 sulphonamides and a neutral marker were examined at pH 7. The resolution between the pairs was improved with the increased concentration of the buffer from 65 mM to 174 mM. Nineteen sulphonamides, a hydrolysis product and several unidentified minor components were baseline resolved in both 101 and 138 mM phosphate buffers. In 174 mM buffer all 21 ionised sulphonamides and the other compounds were separated. A simple relationship between the resolution of analyte pairs (R(s)) and the square root of the mean analysis time for the pair (t(app)) was derived, but few of the pairs displayed this behaviour. For the majority of pairs of compounds, Joule heating appeared to cause a maximum in the R(s) versus t(app) relationship, while non-ideality and shifts in ionisation with increasing salt concentration appeared dominant in other cases.

Publication type

Journal article

Research centre

Swinburne University of Technology. School of Engineering and Science

Source

Journal of Chromatography A, Vol. 849, no. 2 (Jul 1999), pp. 575-585

Publication year

1999

FOR Code(s)

03 Chemical Sciences;  09 Engineering;  10 Technology

Keyword(s)

Buffer composition;  Capillary electrophoresis;  Ionic strength;  Potassium dihydrogen phosphate;  Resolution;  Salt effects;  Sodium chloride;  Sulfonamide;  Sulphonamides

Publisher

Elsevier

ISSN

0021-9673

Publisher URL

http://dx.doi.org/10.1016/S0021-9673(99)00627-5

Copyright

Copyright © 1999 Elsevier Science B.V.

Peer reviewed