Chromatography Forum

Can one use expired material for method validation? The lot came off stability about 3 months ago. This is not expired standard. It is the finished product that would be used in such experiements as accuracy.

Validation isn't exactly my area of expertise, but generally one can do "whatever" as long as it's documented.

For example, we only use real samples in our validations for Precision and Intermediate Precision. Stuff like Accuracy, LOD, LOQ, etc., are done with placebo product that is spiked at various levels with active pharmaceutical ingredient.

Why is there no more-recent product available???

the expired lot has a larger peak of interest for the validation, thereby making integration easier.

Kristin: It will raise a "red flag" to any Auditor who sees that you're using expired materials for anything other than "initial investigatory experiments on a method or instrument". I realize that the peak of interest has better chrom on the expired lot---to circumvent this problem with the in-service lot (albeit having a lower peak height) just lower the attenuation in order to bump up the peak size for the in-service lot of reference material.

Kristin: It will raise a "red flag" to any Auditor who sees that you're using expired materials for anything other than "initial investigatory experiments on a method or instrument". I realize that the peak of interest has better chrom on the expired lot---to circumvent this problem with the in-service lot (albeit having a lower peak height) just lower the attenuation in order to bump up the peak size for the in-service lot of reference material.

The FDA GLP regulations state "Deteriorated or outdated reagents
and solutions shall not be used".(21 CFR part 58.83).

My QA would reject any validation where I used expired material. If your method (validated with expired material) was used to support a GLP study it would have to be documented as an "exception to GLP" in the final report and would cast doubt on all the analytical work. In my opinion it's not worth it, the problems you will cause by using out of date material are better avoided.

How do you know your "expired" material behaves the same as the within date stuff?

The FDA GLP regulations state "Deteriorated or outdated reagents
and solutions shall not be used".(21 CFR part 58.83).

As far as I have understood, she isn't talking about reagents or solutions. She is talking about analytes.

My QA would reject any validation where I used expired material. If your method (validated with expired material) was used to support a GLP study it would have to be documented as an "exception to GLP" in the final report and would cast doubt on all the analytical work. In my opinion it's not worth it, the problems you will cause by using out of date material are better avoided.

Your QA is certainly right in doing that, as you have a SOP about that.
What is the shelf life of soil samples or serum?

Personally I think in GMP expired material can be analysed. My QA would second that. Whats the alternative? When you are forced to do i.e. method precision on impurities and your SOP says they should be close to the spec limit then you are left with either spiking or using stressed samples.

I prefer using stressed (either time or temp./humidity or both) samples.

How do you know your "expired" material behaves the same as the within date stuff?

Its not the material that has to be investigated, Its the method. If a method wasn't able to deal with tablets three months past their expiry date, I wouldn't trust any stabilty data collected to support that shelf life.