The effect of traces of water in nonaqueous solvents on the zeta-potential
is overrated, and the role of impurities in presumably pure organic solvent
s is often overlooked. Oxides can serve as potentiometric sensors to determ
ine the concentration and nature of impurities. Even in very inert solvents
the countercharge in solution must exist. Small ions are stabilized by hom
oconjugation and by amphiphilic nonionic compounds. The electrokinetic phen
omena of the second kind are more common in nonaqueous solvents and they le
ad to very high absolute values of mobility at high field strengths. (C) 19
99 Elsevier Science B.V. All rights reserved.