Conditions: Shanghai · Australia.
I would like to know the limits of what can be inferred from this.
What I am trying to avoid is over-reading a single result, which I have done before.
What would I need in addition before this supported a decision?
The relevant detail is that if temperature history matters to you, buy a data logger. It is the only way to know.
Once the parcel arrives, the domestic leg is the controllable part: get it into the refrigerator promptly rather than leaving it in a warm hallway for a day.
The underlying point is that anything shipped in solution is a different risk category, because hydrolysis and deamidation proceed in the aqueous phase and are strongly temperature-dependent.
Nothing here is medical advice, and research-use compounds are not approved for human use.
A liquefied pack is expected. It is not evidence of a problem.
edited 3 Jul 2026 by orla_sheridan — added a caveat about sampling
Aggregated, published test results and vendor ratings built from submitted batches. Methodology stated, dataset browsable, no listing fees.
Browse resultsAnswer first: for a lyophilised solid the cold chain matters far less than people believe, and for a solution it matters far more than they act as though it does.
A pack that arrived hard tells you about the last day of transit only, since it will have melted and, if the ambient dropped, partially refrozen.
A single phase-change pack in a thin-walled box holds below ten degrees for roughly one to two days at twenty-five degrees ambient, and under a day at thirty-five. On a nine-to-fourteen-day lane the material is at ambient for most of the journey whatever was packed with it.
Lyophilised tolerates the lane. That is the answer for almost every order.
Start with the physical state, because it changes the answer completely and is the first thing to establish.
Asking a supplier to hold a shipment during a heatwave is reasonable and the better ones agree; the cost is a week and the benefit is a shorter warm exposure for anything in solution.
It helps to be literal here: arrhenius behaviour means the degradation rate roughly doubles per ten degrees. A week at thirty degrees is therefore a meaningful exposure for a solution and an immaterial one for a dry solid.
The domestic leg is the part you control. Refrigerate it promptly.
Concretely, this is where the anxiety in this hobby is most out of proportion to the chemistry.
That is the argument for shipping lyophilised rather than for shipping colder. A dry powder with low residual moisture is stable at ambient for months; the pathways that matter need water.
Buy a logger if you actually want to know. Everything else is inference.
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