Assay of Pharmaceutical Products

Assay of products such as pharmaceutical suspensions and tablet coatings is a critical part of the Quality Assurance process. In some cases every batch of each product has to be tested, requiring 100% repeatability of results. 

 

 

The Process

Preparation of samples may involve disintegration of solids such as tablets, dispersion of powders into liquids, intimate mixing of liquid/liquid or liquid/solid components to accelerate reactions, etc. Typical process requirements include: 

• Efficient particle size reduction and homogenization of the sample before testing is essential in order to obtain 100% consistent and repeatable results. 
• The mixing process must be easily and accurately validated. 
• Some methods of disintegrating solids, especially on a small scale in the laboratory are difficult to validate; this can also lead to inconsistency between batches.
• Grinding equipment may be difficult to clean, raising potential contamination/hygiene issues. 
• The mixer must be capable of performing a wide range of tasks depending on the product being tested, for example disintegration of tablets, dispersion of powders into liquids, etc.
• In some cases a single tablet is tested. The mixing apparatus must be capable of processing such small volumes with the same efficiency as larger samples.