Ussing Chamber

The Ussing chamber system is named after the Danish zoologist Hans Ussing, who invented the device in the 1950s to measure the short-circuit current as an indicator of net ion transport taking place across frog skin (Ussing and Zerahn, Acta Physiol Scand 23:110-127, 1951). Ussing chambers are increasingly being used to measure ion transport in native tissue, like gut mucosa, and in a monolayer of cells grown on permeable supports. However, the Ussing chamber system is, to date, not often applied for the investigation of the impact of food bioactives (proteins, sugars, lipids) on health. An Ussing system is generally comprised of a chamber and a perfusion system, and if needed, an amplifier and data acquisition system. The heart of the system lies in the chamber with the other components performing supporting roles. The classic chamber design is still in wide use today. However, several newer designs are now available that optimize for convenience and for diffusion- or electrophysiology-based measurements. A well designed Ussing chamber supports an epithelia membrane or cell monolayer in such a way that each side of the membrane is isolated and faces a separate chamber-half. The chambers are then filled with a physiologically relevant solution, such as Ringer’s solution. This configuration allows the researcher to make unique chemical and electrical adjustments to either side of the membrane with complete control. The Ussing chamber technique has its strengths and limitations, which will be explained in more detail in this chapter.