Accepted answer
At 37 °C the question is which route is fastest, not whether dimerisation happens — and the routes do not share an activation energy, so their ranking changes with temperature. 37 °C is 32 kelvin above the 5 °C middle of a 2–8 °C refrigerator. The ten-degree rule of thumb — degradation rate roughly doubling per 10 K — makes that about 9.2 times the refrigerated rate, which is an order-of-magnitude statement and not a shelf life. That multiplier is an average over every route at once, which is exactly why it cannot tell you which one wins. Two chains join, usually through a disulfide, so the product is roughly twice the mass and shows up as a late peak — or as nothing, if it never comes off the column. So the way to answer it for your vial is to pick the method that sees dimerisation specifically and run it against a control held cold, rather than to infer a mechanism from a purity number that averages all of them.
The honest answer is that most reported "degradation" is adsorption and dilution error rather than chemistry.
Adsorption onto glass and plastic is significant at low concentrations — micrograms per millilitre — and negligible at milligrams per millilitre. It is the usual explanation for an apparent loss in a dilute preparation.
Light exposure matters for tryptophan-containing sequences and for anything with a chromophore. Amber vials and a closed box are free mitigations.
Aggregation at air-liquid interfaces is established from surface-tension and particle-count studies and is the basis for anti-agitation handling guidance.
Nothing here is medical advice, and research-use compounds are not approved for human use.
Swirl, never shake. Aggregation is a handling problem more than a time problem.
7The doubling-per-ten-degrees rule is the part I did not know and now use constantly. – bac_or_bust 3 months ago 8I would add a sentence about light, since tryptophan-containing sequences care. – Dr_Colm_Fitzhenry 5 months ago add a comment