11.25 : 電気泳動: 概要

Electrophoresis uses the differential migration rate of charged species in an applied electric field. The greater the charge-to-size ratio, the faster the rate of migration through the gel.

Slab electrophoresis is performed on a thin, flat layer of porous semisolid gel containing an aqueous buffer solution.

The samples are placed as spots or bands in the sample well, and an electric field is applied across the slab. Post-separation, the distinct components are visualized using UV light or other staining techniques.

It is widely employed in DNA sequencing and analysis of mixtures.

Capillary electrophoresis, or CE, is more suitable for quantitative analysis.

CE employs a conducting buffer within a capillary tube. The sample is injected into one end of the tube.

Migrating sample components are influenced by electrophoretic mobility, which is the solute's response to the electric field.

They are also affected by electroosmotic flow arising from the movement of buffer solution through the capillary due to the electric field.

The migrating components eluting from the capillary at different times are recorded in an electropherogram.