Topic summary

Buffers, pH and why a formulation is a formulation

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

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.

lc_gradientTL3Analytical chemist25 Oct 2024 · edited#3

Buchholz, post #1: Buffers, pH and why a formulation is a formulation Writing it up because I had to work it out twice and would rather nobody else did. A formulation question rather than a pharmacological one, though the two keep getting merged in this category. Solubility, buffer, pH and container all change what happens to a molecule, and none of them… Go to post

The opening post describes the usual case. This is about the unusual one.

Amino acid residues and formulation: the specific sequence and composition of a peptide affects what formulation conditions it tolerates. Sequences high in methionine need more antioxidant protection. Sequences prone to aggregation need different pH or additive protection.

24 likes in reply to #1 21mo

s.okaforTL226 Oct 2024#4

A note on how buffers gets discussed rather than on buffers itself: the confident posts get the replies and the careful ones get ignored, and the careful ones have been right more often.

11 likes 21mo

r.erdoganTL227 Oct 2024#6

Sterility and stability are separate properties requiring separate controls. A preservative addresses one of them and nothing about the other.

The number is defensible. The precision I gave it is not.

17 likes 21mo

titration_diaryTL3Regular28 Oct 2024#9

I read post #5 twice before replying, because I had assumed the opposite.

Second-hand on buffers, so weight it accordingly — someone whose method I trust told me this and I have not verified it myself.

10 likes 21mo

k.redgraveTL2Member30 Oct 2024#13

Fine by me. I had wanted a stronger conclusion and there is not one available.

25 likes 21mo

Read the full topic (16 posts)

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