1998 WAE McBryde Medal Lecture - Searching for the Holy Grail in analytical separations

This paper describes the chemistry presented during the W.A.E. McBryde Meda l address given at the 81st Chemistry in Canada Conference held in Whistler . The narrative chronicles our Quest to perform isotopic separations in the solution phase using as our Excalibur, capillary zone electrophoresis. The narrative takes you through the highs of our early success in separating C l-35(-) and Cl-37(-). This separation was achieved by adjusting the electro osmotic flow to be equal in magnitude but opposite in direction to the chlo ride mobility. The narrative then takes you through the dark days, when we could not extend the isotopic separations to cationic species or even expla in why there was an isotopic effect on mobility. Since those dark days, we have made numerous discoveries that have aided our Quest. Firstly, the deve lopment of mixed surfactant wall coating procedures yielded control of the reversed electroosmotic flow. This control enabled us to perform isotopic s eparations of systems such as N-15-/N-14-aniline and (NH4+)-N-15/(NH4+)-N-1 4. In terms of understanding electrophoretic mobility, we demonstrate the i mportance of dielectric friction to mobility. Further, the effect of ionic strength in capillary zone electrophoresis is explained using the Pitts tre atment, which is analogous to the extended Debye-Huckel equation for ionic activity. So, have we completed our Quest? Read on.