Preservation of TOC samples

Hi all,

I would like to know your opinion about how to preserve TOC samples for cleaning validation:

          - What is better: maintain the swab in the vial in WFI or dry until the assay? Why? 

          - I have read that it is recommended that if we are going to analyze the samples 24h after sampling, it is recommended to maintain them at 2-8ºC in an acid media. Is this correct?

Thank you very much in advance!

As per my experience, it can be decided by “solution stability” test results in your analytical method validation.
If you can prove that your standard solution yields same test results, even after 24 hours, when stored at room temperature, you can store in normal sampling container. But, if you found any degradation, you need to look for a suitable container and storage condition for your sample.

Regards
Veerraju Nalla