When it comes to measuring the release rates of drugs in a manufacturing environment then the technique of Tablet Dissolution testing is employed.
Tablet Dissolution is a standardised method for measuring the rate of drug release from a dosage form and the key word here is “standardisation" because for any results to be meaningful, it is essential that all the apparatus used for the testing, produces the same sets of results given all other parameters are equal.
There are many discussions about how good dissolution testing may or may not be compared with the actual in-vivo effects, but without a standardised test it is impossible to gain comparative data.
The principle function of the dissolution test may be summarised as follows:

• Optimisation of therapeutic effectiveness during product development and stability assessment.
• Routine assessment of production quality to ensure uniformity between production lots.
• Assessment of ‘bioequivalence’, that is to say, production of the same biological availability from discrete batches of products from one or different manufacturers.

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