Sampling in cleaning validation:
Direct sampling (swab test) .
There are two sampling methods which are most used and are accepted by regulatory agencies world wide , they are direct sampling methods that is the sampling of surface of the equipment and rinse solutions .
The advantages of direct sampling method in cleaning validation is that the surfaces of equipments and machines which are otherwise difficult for cleaning can be evaluated for their cleanness after cleaning.
The effectiveness of this method should be evaluated properly the sampling adhesives in swab many time have tendency to interfere with the test, therefore in while making the validation program and cleaning validation protocol the materials used for sampling should be verified for their interference. The residues which get dried or are insoluble can be directly sampled by physical means.
Rinse water (Rinse solution sampling, rinse water analysis).
The advantage rinse sampling is that the large aria of the surface of equipment can be sampled and evaluated. The areas which are otherwise not accessible for direct sampling can be washed with the rinse solution and the rinse sample can be analyzed for the residue after cleaning. Rinse water, rinse solution sample can be taken over from the parts of equipments which can not be disassembled.
Alternative method for sampling should be adapted when the residue becomes insoluble and occlude the equipment, observing the equipment by a quality assurance personal physical is of importance in such cases.
Only rinse water quality test for contamination is not acceptable by regulatory agencies rather they want the evaluation whether it meets the required limits and whether it can assure that the cleanness of equipment when it is used during cleaning validation, it should be able to test it for potential contaminates.
good manufacturing practices
Cleaning validation series:
Sterile drug product validations
Aspects of Validation of Aseptic Process and Sterilisation , Sterilization of Equipment, Containers, and Closures
Pharmaceutical Process Validation Series
Quality by design concept for pharmaceutical industry
Quality by design concept in pharmaceutical industry an explanation