Isotachophoresis

Isotachophoresis (ITP) is an analytical procedure used for example in the testing of water samples.

The ions to be analyzed are separated in the electrolytic solution in an electric field. This is due to different ion mobilities. By using a discontinuous buffer system with a common counter-ion, the different ions move in accordance with the separation with the same speed. Hence the name of iso ( ἴσος ) = and stirred equal tachos ( τὸ τάχος ) = speed.

To use an electrolyte having a high ion mobility and thus in the field moves fast. This is located in front of the sample into the separation capillary and is therefore called Leading electrolyte. An electrolyte having a low ion mobility and thus the field slowly moves, is located behind the specimen in the separation capillary, and is therefore called a terminating electrolyte. Since the field between these two electrolytes has special properties, receive all ions between a certain order and concentration. These are independent of the initial state.

The procedure is similar to the chromatography.

The use of a Sammelgels on SDS gel electrophoresis of proteins, is also based on the isotachophoresis.

• Electrophoresis