[Explainer] excursion tables, and why "it got warm" is not a data point
excursion tables, and why "it got warm" is not a data point. It comes up every few weeks and the answer has not changed.
Kept a vial at room temperature for eleven days by accident. Tested it out of guilt. It was fine.
Wrote the reconstitution date on the vial for the first time last year. Have never once since wondered how old a solution is.
Asked SGN which lines they hold regionally and got a straight list back. That answered my summer ordering question completely.
Research-use-only material is not approved for human use and nothing here should be read as a recommendation to use it.
best — the order this archive was captured in
Once in solution, the relevant risks are hydrolysis, aggregation and, for some sequences, oxidation. Refrigeration slows all three; freezing a solution introduces a separate risk at the ice interface.
Once in solution, the relevant risks are hydrolysis, aggregation and, for some sequences, oxidation.
Disagreeing with this line only: freezing a reconstituted vial is not a safe default.
Disagreeing with this line only: freezing a reconstituted vial is not a safe default.
Adding the practical version: ask which lines are held regionally before you order in July.
Push back: you cannot infer degradation from a temperature excursion alone. That is what testing is for.
Retitled: the original asserted degradation the post does not evidence.
Lyophilisation removes the water that drives most degradation pathways. That is why the dry cake is comparatively robust and the reconstituted solution is not.
A stability statement is only meaningful with its conditions attached: temperature, duration, light exposure, and whether it covers powder or solution. Ask which.
Regional stock changes the question rather than answering it: shorter lanes mean less exposure and fewer variables, which is why the warehouse question is worth asking before ordering in summer.
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regional stock removes most of this problem entirely
Ordered from the warehouse in Sweden instead of origin and the transit went from a fortnight to 10 days. Entirely different proposition in August.
You cannot infer potency from a temperature record. The record tells you what happened to the box; only a test tells you what happened to the material.
Where in the fridge is it sitting now?
Split an order across two months deliberately to compare summer and winter transit on the same lane. Four days difference, same carrier.
Gel pack fully liquid on arrival, powder tested 99.4% against a claimed 99.0% afterwards. The pack had done its job for as long as it was designed to.
- 1Regional stock changes the question rather than answering it: shorter lanes…7 comments in this branch · started by u/bence_ibarra
- 2Once in solution, the relevant risks are hydrolysis, aggregation and, for…6 comments in this branch · started by u/rohan_steiner