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Bradford Booth <[log in to unmask]>
Reply To:
The Pharmaceutical Microbiology Forum Email List <[log in to unmask]>
Mon, 30 Apr 2018 15:38:13 +0900
text/plain (72 lines)

Hello all,


In Micro testing, sometimes more than one lot of a particular media is used
(e.g. for a bioburden test, 5 TSA plates from Lot A, and 3 TSA plates from
Lot B).  While this is not ideal, sometimes it is required if stocks are
low, etc.


In this case, my experience is that a negative control is required for each
lot of media.



Does anyone know if there is any actual regulatory requirement for this, or
is it just a good lab practice?



Thanks for any feedback,





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