Topic summary

Second pass at: Adsorptive losses at low concentration, and why dilute solutions are fragile

Practice › Storage & stability beyond-use date freeze-thaw cloudy or discoloured solution storage temperature excursion Closed

This is a generated summary. It shows the 9 most-liked posts from a topic of 88, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

v.malinowskiTL224 Dec 2025#6

I had written a reply contradicting post #4 and deleted it. Here is what survived.

On Adsorptive losses I would separate what is worth knowing from what is worth acting on. The first list is long and the second is short, and conflating them is how threads get heated.

28 likes 7mo

k.roosTL213 Jan 2026#17

Post #15 put the caveat in the right place and I want to underline it.

On Adsorptive losses, I would rather understate and be corrected upward than overstate and be quoted. That is a house style here and it is a good one.

32 likes 6mo

chromatogramTL4Analytical chemist22 Jan 2026#23

z.nakamura, post #19: Adsorption to container surfaces removes peptide from solution without changing how the solution looks. In dilute preparations that loss can be a meaningful proportion, and it is invisible. That is the practical version. The rigorous version is longer and says the same thing. Go to post

I want to gently push back on the reply above about storage extrapolation. The advice is sound and the confidence is not.

We are extrapolating from stability data on a licensed formulation to a preparation that differs in concentration, diluent and container. That extrapolation is reasonable and it is still an extrapolation. Saying so does not weaken the practical recommendation; it just stops the recommendation from hardening into a fact that someone cites as certain.

It reads as pedantry until the day it does not.

30 likes in reply to #19 6mo

r.venkatesanTL3Wiki editor5 Feb 2026#33

Clarity is a weak test. A solution can lose a significant fraction of its active content to degradation or adsorption while remaining perfectly clear.

I am confident about the direction and much less about the magnitude.

28 likes 6mo

t.marchettiTL214 Feb 2026#40

Reading rather than contributing, but this is the most useful thread I have found on it.

29 likes 5mo

e.adeyemiTL222 Feb 2026#47

I want to gently push back on the reply above about storage extrapolation. The advice is sound and the confidence is not.

Happy to be the one who is wrong here if it settles the question.

27 likes 5mo

sourced_claimsTL3Regular14 Mar 2026#63

a.jansen, post #41: This follows post #38 rather than contradicting it. Where I have landed on Adsorptive losses, having got it wrong once in public: the direction is clear, the magnitude is not, and anyone quoting a precise magnitude has borrowed it from somewhere that did not measure it. Go to post

An observation about Adsorptive losses that I cannot explain and am posting anyway, on the principle that unexplained observations are more useful public than private.

32 likes in reply to #41 4mo

b.oseiTL222 Mar 2026#70

Helpful, and short, which on this subject is harder than long.

31 likes 4mo

RodriguesTL3Regular25 Mar 2026#73

d.szymanski, post #46: On Adsorptive losses: the maintained page in the documentation commons covers the general case with citations and a review date, which is more reliable than any reply here including this one. Go to post

Clear enough that I do not think I have a follow-up, which is unusual.

30 likes in reply to #46 4mo

Read the full topic (88 posts)

This topic was referenced in

What published stability data actually covers, and what it does notPractice › Storage & stability · 12 replies
Revisiting: Power cut for eleven hours: how I assessed it afterwardsPractice › Storage & stability · 4 replies

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