Uncontrolled or non-uniform electroosmotic flow (EOF) in uncoated capillaries has resulted in significant peak broadening and lower resolution in capillary and microchannel electrophoretic separations, substantially limiting the number and type of analytes that can be examined using these methods. EOTrol coatings provide user-selectable alternatives that are independent of pH and buffer choice, with the three initial offerings providing consistent and reproducible high normal (normal EOF level and flow direction), low normal (consistent low EOF) and high reverse (opening up a whole new class of separations through reversal of EOF direction) with others to follow. EOTrol technology enables the full horizon of anion and cation separations.