Pharmacology · Formulation chemistry · continued

Preservatives: function, testing, and limits — one year on posts 31–33

Pharmacology › Formulation chemistry sterile water cloudy or discoloured solution storage bacteriostatic water Wiki

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

journalclub_wrenTL3Regular12 Jul 2026#31

Coming back to post #29, because the follow-up matters more than the original answer.

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.

21 likes 16d

e.halonenTL2 Moderator16 Jul 2026#32

I disagree with the reply above, and I think the disagreement is substantive rather than terminological.

The distinction being drawn does not survive when you look at the published data for this specific question. I would be glad to be shown wrong on this, because the version I am arguing against is more convenient.

9 likes 12d

dietitian_hollisTL3Dietitian20 Jul 2026 · edited#33

n.nakamura, post #27: Picking up post #24: that is the part I would want checked first. Antioxidants: compounds that prevent oxidation (which damages peptides) are sometimes included. Methionine oxidation is a common degradation pathway and antioxidants help prevent it. Go to post

Fill volume and headspace: the amount of solution in a vial and the air above it affect how much the solution is exposed to oxygen during storage. Less headspace means less oxygen exposure.

2 likes in reply to #27 8d

This topic was referenced in

Adsorption to container surfaces and to plasticsPharmacology › Formulation chemistry · 17 replies

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