Some Hints for Selecting a Detergent
The number of detergents which can be used in the various fields of biotechnology is immense. Finding the right detergent for a special application, can therefore be a difficult and tedious task. To begin with, a survey of scientific publications on this topic will be helpful. A detergent which has been used successfully for the isolation of a similar membrane protein, enzyme or receptor should be tried first. Other detergents with similar or slightly different properties can be tried in additional tests.
If the isolation process involves a dialysis step, detergents with a high CMC are preferred as they bind less strongly to proteins than detergents with low CMC. For electrophoretic separation or ion exchange chromatography, nonionic or zwitterionic detergents are recommended.
To maintain the biological activity of an isolated membrane protein, it may be necessary to test not only different detergents, but also each detergent under different conditions, e.g. concentration, pH, buffer composition etc. Generally, nonionic and zwitterionic detergents are milder than ionic ones and better suited to preserve biological and enzymatic activity.