Bioequivalence and Bioavailability Forum

Dear Suchit!

❝ My query is that Do we need to maintain desiered temperature as specified per protocol during segregation?

I’m not sure whether I do understand your question in connection with the subject line.
Hopefully you have validated the stability of your analyte from collection of whole blood until analysis [including stability in whole blood, cooling (e.g., on ice, thermostated waterbath) until centrifugation, temperature and duration of centrifugation,^[1] time needed to transfer plasma to sample vials, long term storage, temperature control at shipment,^[2] freeze-thaw cycles, benchtop stability,…).

If your analyte is very temperature-sensitive, it might be an option to shock-freeze matrix (liquid nitrogen or dry-ice in alcohol) instead of transferring them directly to a –80 ℃ freezer. Air has very poor thermal conductivity and it will take samples quite a while to reach the required low temperature. For some analytes alternatively you may add a stabilizer already to whole blood, avoiding temperature-related problems. Search the literature.

❝ and we have to keep record for that?

Yes.

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1. Even if the refrigerated centrifuge’s temperature reading is something like +4 ℃, samples might heat up. Sometimes it’s better to apply lower g-force for longer time. Check that.
   
2. Preferably use an electronic data logger with two sensing heads; one placed outside the primary container in dry ice and the other one between samples. I have seen partly thawed samples, where the logger was placed at the lowest part of the outer container where still a bit of dry ice was left. Of course the log was meaningless.