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c/coldchain·posted 21 days ago by u/ines_lindqvist

freezing reconstituted product: why the answer is no

Data Sourced ×6 Slow Clap ×2

freezing reconstituted product: why the answer is no. Not a hot take, just something I have not seen said plainly here.

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.

On loggers, since I was sceptical and then bought one.

A small transit logger costs a fraction of a vial and records the whole journey rather than the moment of arrival. What I learned from three of them: my lane is far more stable than I assumed, the one excursion I did capture was on a weekend, and the arrival-temperature guessing I had been doing was worthless.

If you are going to argue about cold chain, argue from a chart. It is a one-off purchase and it ends the speculation permanently.

Seasonality, which the source-page lane tables show clearly once you look for it.

The same origin, destination and carrier can differ by several days between February and August, and the temperature exposure differs by much more than the transit time suggests. A lane that is uneventful in winter is the same lane that generates the summer threads.

Two practical consequences. First, compare like months when you compare lanes. Second, ask which lines a supplier holds in regional stock — a shorter leg in July is worth more than any amount of packaging.

If two or three other people have done the same thing we might actually learn something. Alone it is an anecdote.

1,851 up / 668 down73% upvoted53 commentsid qnovos9 Jul 2026

53 comments

22 in this archive, depth 5

best — the order this archive was captured in

u/marta_ilunga190 points·20 days ago

A stability statement is only meaningful with its conditions attached: temperature, duration, light exposure, and whether it covers powder or solution. Ask which.

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u/ines_lindqvistOP72 points·19 days ago

fridge, not freezer, once it is in solution

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u/emeka_delgado79 points·19 days ago

I would not freeze it in solution. That is a different failure mode and a worse one.

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u/rohan_steiner27 points·19 days ago·edited

I would not freeze it in solution.

This is the distinction that resolves most threads here — powder and solution are different problems.

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u/ilias_steiner7 points·19 days ago

ask which lines are held in regional stock before you order in July

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u/hplc_hobbyistruns their own column21 points·19 days ago·edited

Small fix — refrigerated, not frozen, once it is in solution.

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u/rohan_steiner100 points·19 days ago

the door shelf is the worst place in the fridge

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u/priya_weiss88 points·19 days ago

Moved everything off the fridge door after reading a thread here and my temperature log immediately got boring.

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u/marta_ilunga129 points·18 days ago

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.

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u/ines_lindqvistOP66 points·18 days ago·edited

Do you know what storage condition the stability statement covers?

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u/emil_marchand46 points·17 days ago

Correction: that stability figure covers the lyophilised powder, not the reconstituted solution. Different claim entirely.

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[removed]30 points·17 days ago

[removed by moderator]

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u/isabela_nilsen60 points·18 days ago

How many days in transit, and which month?

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u/nightowl_injector65 points·20 days ago

write the reconstitution date on the vial

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u/ice_pack_auditMOD42 points·20 days ago

Merged into the seasonal thread for that lane so the reports sit together.

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u/noor_cardoso-3 points·20 days ago

a summer lane and a winter lane are different lanes

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u/nadia_kjaer14 points·20 days ago

Yes — reconstitution date on the vial. It is the number you will want and cannot reconstruct.

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u/usb_logger_ursula17 points·19 days ago

Gel pack fully liquid on arrival, powder tested 97.8% against a claimed 97.0% afterwards. The pack had done its job for as long as it was designed to.

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u/nadia_kjaer20 points·19 days ago

light matters more than people think for some of these

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u/noor_cardoso10 points·19 days ago

Where in the fridge is it sitting now?

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u/ireland_drugs_pay15 points·18 days ago

regional stock removes most of this problem entirely

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u/chidi_abubakar22 points·20 days ago

Careful. "The cold chain failed" is a strong claim and the evidence you have is a warm box.

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About c/coldchain

Temperature and stability in the real world: what an excursion actually costs you, why lyophilised powder is far more forgiving than reconstituted solution, how to read a logger CSV, and how to photograph a failed shipment so the conversation with the vendor is short.

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