A SmartUSSING System, used to measure transport across epithelial membranes, is generally comprised of a chamber and 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, first introduced by the Danish physiologist Hans Ussing in the early 1950’s, is still in wide use today. However, several newer designs are now available that optimize for convenience and for diffusion or electrophysiology based measurements. 

Epithelia are polar structures possessing an apical (or mucosal) and basolateral (or serosal) side. It is the movement of electrolytes, nonelectrolytes, and H2O. Ussing systems have been used to make measurements from native tissue including stomach, large and small intestine, gall and urinary bladder, skin, and trachea, as well as from tissue derived cell monolayers from various sources including renal tubes, pancreas, and salivary and sweat glands. 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. This configuration allows the researcher to make unique chemical and electrical adjustments to either side of the membrane while maintaining complete control.

An electrophysiology based SmartUSSING-System focuses on measuring transepithelial electrical responses to experimental perturbations. These systems are used to quantify the operation of electrogenic pathways in the membrane (for example, ion pumps, channels, etc). As such, an electrophysiology based system carries the additional hardware requirement of a voltage and/or current clamp amplifier, a data acquisition system, and data acquisition and analysis software. 

Basic measurement parameters in electrophysiology based systems include transmembrane voltage (Vt), epithelial membrane resistance (Rt), and short circuit current (ISC).

While a single SmartUSSING chamber block can hold from 1 to 6 chambers, multiple systems can be operated in parallel on a single computer giving you the flexibility to work with up 24 chambers in parallel. Each block is controlled with its own USSING Control software.

Hardware Components

The SmartUSSING-System is complete with up to six included chambers and amplifiers, air/gas fitting kit, electrode set and support stand with an option to connect a thermocirculator for thermostatic temperature control of the front and back plate. USSING chambers are available in a variety of sizes and shapes. 

Chamber Types

Different types of USSING chambers are available. All USSING chambers have the following features in common: holding the membrane while minimizing tissue damage, holding and exchanging solutions, a way to facilitate electrode placement, and a way to control temperature and gas load.

Example:  Vertical Chamber

To see options please locate them here on the Warner Instruments website. 

Epithelial Voltage Clamp Amplifier

This small amplifier is specifically designed for studies of epithelial transport and the electrical properties of tissue. It features high common mode rejection, multiple clamp speed selection, membrane resistance measurement circuitry, and a watertight headstage that includes a model membrane. 

Air Manifold

The air manifold for this diffusion chamber has been specially designed for use with mixed oxygen gases. Oxygen in the presence of hydrocarbons is combustible. Do not use this manifold to deliver gases which contain traces of hydrocarbons. Medical grade gases are recommended. Routine maintenance extends only to replacing the air lines, please do not open the air manifold by removing the fittings as this can introduce contaminants into the clean environment. 

Thermocirculator

Set up instructions for the thermocirculator can be found here. 

Technical Specifications: