Bioassays and biological stability.

The development of the concept of <>, made possible through the power and detail afforded by modern biochemical and biophysical techniques, has resulted in questions being raised about the value of the more variable bioassay. However bioassays, particularly in a routine stability monitoring situation, continue to be useful and often provide unique information not obtained by other techniques. They have advantages in that they are relatively easy to perform and generally have better sensitivity than most structural techniques. They can be used to monitor for previously undetected changes - particularly those associated with conformational alterations, and can be used to monitor the effective combination of all individual changes.