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Electrophoresis can be defined as the migration and separation of charged particles (ions) under the application of electric field. The system consists of two electrodes of opposite charges that is, anode and cathode which are connected by the medium known as electrolyte. The isoelectric point is the pH of an aqueous solution of an amino acid at which the molecules on average have no net charge. In an acidic solution, amino acids exist as cation, thus the movement of amino acid will be towards cathode which is the negative electrode. Movement of amino acid will be towards anode in basic solution when amino acids exist as anion.

The movement of amino acids towards anode or cathode will depend on the overall charge the amino acid is carrying at pH 9.7. At pH 9.7, alanine has isoelectric point 6.0, and has a charge of -1, hence will migrate towards anode which is the positive terminal. Lysine which has isoelectric point of 9.7 will not move as it has zero charge and aspartic acid having isoelectric point of 2.8 has a charge of -2 and thus will migrate towards the anode faster than alanine.

Electrophoretic separation of Ala, Lys, and Asp at pH 9.7