Topic summary
Lyophilisation and why the cake looks the way it does
This is a generated summary. It shows the 5 most-liked posts from a topic of 38, 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.
For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
32 likes 12mo
desiccant_notes, post #1: Posting this under the heading it deserves: Lyophilisation and why the cake looks the way it does Everything below is what sits behind that. I would like to understand what this number means before I repeat it anywhere. A Medutest report on a retatrutide lot gives 98.9% purity. The supplier certificate for the same lot states 98.5%.… Go to post
post #13 is right about the mechanism and I think understates the practical bit.
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.
isotonic_review, post #6: On post #2 — agreed on the reasoning, with one qualification. Container closure: the vial material, rubber closure, and sealing all affect permeability to water and oxygen. Glass is less permeable than plastic. Rubber quality matters. Go to post
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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.
j.moreau, post #30: I read post #28 twice before replying, because I had assumed the opposite. 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. Go to post
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.
Read the full topic (38 posts)
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