Capillary electrophoresis separation of p-sulfonated calix[n]arenes, n=4,6,8

The CE separation of p-sulfonated calix[n]arenes, where n=4,6 and 8, was investigated. Under positive potential conditions optimum separation was found to be borate buffer modified with sodium dodecyl sulfate. Under these conditions separation was achieved in less than 10 min. The effect on the separation of the addition of divalent cations: Mg(2+), Ca(2+) and Ba(2+) was studied. p-Sulfonatedcalixarenes were detected in the anodic side of the capillary. There was an improvement in the reproducibility and analysis time although efficiency did not improve significantly.