Patent ID: 7052589

Claim:
A method for electrophoretically altering the initial composition of a feed solution containing at least two components, entities A and B, comprising: providing an electrophoretic apparatus having a separation chamber and a pair of electrodes; providing a separation medium containing a selected resolving agent R at a selected concentration [R] to cause the bands of entities A and B to have an effective electrophoretic mobility μ eff A and μ eff B and separation selectivity, α, where μ A eff = μ A 0 + μ AR 0 ⁡ [ R ] 1 + K AR ⁡ [ R ] and μ B eff = μ B 0 + μ BR 0 ⁡ [ R ] 1 + K BR ⁡ [ R ] α = μ A eff μ B eff = μ A 0 + μ AR 0 ⁢ K AR ⁡ [ R ] μ B 0 + μ BR 0 ⁢ K BR ⁡ [ R ] ⁢ 1 + K BR ⁡ [ R ] 1 + K AR ⁡ [ R ] and μ 0 A , μ 0 B , μ 0 AR , and μ 0 BR are the ionic mobilities of entities A, B, AR and BR, K AR and K BR are the respective equilibrium coefficients characterizing the interactions of entities A and R in forming entity AR and B and R in forming entity BR, and [R] is the species concentration of the free resolving agent R, wherein when at least one of μ 0 A or μ 0 B is not equal to zero, the selected resolving agent R is selected to cause at least one of the ratios μ 0 A /μ 0 AR or μ 0 B /μ 0 BR to be less than or equal to zero, and [R] is selected to cause a to be less than or equal to zero; applying an electric potential between the pair of electrodes; and collecting a desired fraction from the eletrophoretic apparatus; wherein the effective electrophoretic mobility of the bands of entities A and B are equal in magnitude and opposite in sign.