secondary reference standard qualification

[MestizoJoe]

Hi,

I have been instructed to proceduralize the qualification of secondary reference standards. Does anyone know where I can find some guidance (USP?) on this? I searched USP but didn't find anything.

Thanks,

[krickos]

Hi

Definitions and minor guidance is mentioned in ICH Q7 (www.ich.org)

As I recall (away and do not have acess to online USP) there is some more guidance in USP, unsure on chapter.

Generally speaking a secondary standard is qualified against a primary one. The amount of qualification may depend of purpose, is it for SST only, identity or assay or all? This impact in general the frequence of requalification of the secondary standard and accumalated knowledge of stability/physical properties of the substance in question.