In reverse Electro Osmotic Flow (EOF), reverse polarity is used and therefore negatively charged species (Anions) will migrate to the anode and will be swept past the detector as well by the EOF which is now in the opposite direction.
All positively charged species (Cations) which migrate to the cathode may or may not be slowly swept past the detector by the reverse EOF much later than the anions would. In either mode, (normal or reversed polarity) neutral compounds will move at the speed of the EOF and will not be separated from each other.
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