Topic summary

Solubility limits and what a cloudy solution is telling you

Pharmacology › Formulation chemistry cloudy or discoloured solution storage counter-ion content

This is a generated summary. It shows the 5 most-liked posts from a topic of 16, 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.

s.solbergTL2 Moderator23 Jan 2026 · edited#2

Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up.

19 likes 6mo

v.salgadoTL2 Moderator14 Mar 2026#5

Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing.

The correction was fair and I had been repeating something I had not checked carefully enough.

27 likes 4mo

s.coelhoTL2 Moderator6 May 2026#9

Coming back to post #7, because the follow-up matters more than the original answer.

Buffers and pH: the pH of a solution is buffered to maintain stability. The buffer system (phosphate, Tris, or other) is chosen to keep the solution at the pH where the peptide is most stable.

20 likes 3mo

t.batistaTL2 Moderator23 Jun 2026#13

Isotonicity: an isotonic solution has the same osmotic pressure as blood. Non-isotonic solutions can cause discomfort on injection. Injectable peptide solutions are formulated to be isotonic.

15 likes 1mo

bench_peakTL3Regular5 Jul 2026 · edited#14

Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing.

The correction was fair and I had been repeating something I had not checked carefully enough.

30 likes 23d

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This topic was referenced in

About the Formulation chemistry categoryPharmacology › Formulation chemistry · 4 replies
[2026 update] Buffers, pH and why a formulation is a formulationPharmacology › Formulation chemistry · 2 replies

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