Capillary electrophoresis is a separation technique that is used to separate and analyze ions based on their electrophoretic mobility. It involves the use of a narrow-bore capillary tube filled with an electrolyte solution, through which an electric field is applied. The analytes in the sample are separated based on their differential migration under the influence of the electric field. This method is often used in analytical chemistry and biochemistry for the separation and quantification of different compounds.