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Intersection · Analytics × water content

Analytics topics tagged water content

Topics in Analytics carrying the tag water content. Karl Fischer titration and residual water in lyophilised material.

23 topics

TopicParticipantsRepliesViewsActivity
Named, unnamed and unspecified impurities as regulatory categories — the long version
Named, unnamed and unspecified impurities as regulatory categories — the long version — setting out what I have, and where I think it stops being reliable. Two reports on the same lot, and I would like help…
PNTDHFEFJR+112 120 7.6k 5h
Deletion sequences: expected mass shifts by residue — the long version
On the subject in the title: Deletion sequences: expected mass shifts by residue — the long version Working notes rather than a conclusion. Deletion sequences keeps being re-asked here and I think that is…
DBNASCPWEH+21 25 6.9k 10h
About the Impurities & related substances category
Deletion sequences, oxidation, deamidation, aggregates, residual solvents, and counter-ion content. This post is a community wiki: any member at trust level 3 or above can edit it, and every edit is recorded…
BNHSDSSDBW+6 10 50k 15h
Impurity thresholds: where the common numbers come from
Impurity thresholds: where the common numbers come from — setting out what I have, and where I think it stops being reliable. I have spent a fortnight trying to pin impurity thresholds down and I want to set…
MRDNLAPOBP+11 15 825 2d
Racemisation and why it is invisible to a mass measurement — what changed since
Racemisation and why it is invisible to a mass measurement — what changed since Writing it up because I had to work it out twice and would rather nobody else did. What changes if the standard account of…
TVBVCCBIN+11 15 42k 16d
Second pass at: Where impurities in solid-phase peptide synthesis come from
Second pass at: Where impurities in solid-phase peptide synthesis come from Writing it up because I had to work it out twice and would rather nobody else did. Impurities in solid-phase peptide synthesis, from…
GHDBEVLSMP+4 8 7.2k 1mo
Residual solvents and scavengers: what is looked for — what changed since
Residual solvents and scavengers: what is looked for — what changed since — setting out what I have, and where I think it stops being reliable. What changes if the standard account of Residual solvents and…
ESOFIASLC+37 41 7k 2mo
Named, unnamed and unspecified impurities as regulatory categories
On the subject in the title: Named, unnamed and unspecified impurities as regulatory categories Working notes rather than a conclusion. Two reports on the same lot, and I would like help deciding whether they…
DWZONPBNVK+10 14 504 3mo
Impurity thresholds: where the common numbers come from — what changed since
Posting this under the heading it deserves: Impurity thresholds: where the common numbers come from — what changed since Everything below is what sits behind that. What changes if the standard account of…
NAKBMM 2 61k 3mo
Deletion sequences: expected mass shifts by residue
Deletion sequences: expected mass shifts by residue — setting out what I have, and where I think it stops being reliable. Deletion sequences keeps being re-asked here and I think that is because the answer is…
SCBBCN 2 59 3mo
Where impurities in solid-phase peptide synthesis come from
Where impurities in solid-phase peptide synthesis come from Writing it up because I had to work it out twice and would rather nobody else did. Impurities in solid-phase peptide synthesis, and specifically the…
LCDSPOCLNK+54 59 14k 3mo
Endotoxin and why it is a separate question from purity
Endotoxin and why it is a separate question from purity Writing it up because I had to work it out twice and would rather nobody else did. A question about endotoxin that I think has a definite answer, unlike…
DNSGMB 2 22k 4mo
Second pass at: Where impurities in solid-phase peptide synthesis come from
Posting this under the heading it deserves: Second pass at: Where impurities in solid-phase peptide synthesis come from Everything below is what sits behind that. Working notes on impurities in solid-phase…
SABJBPJSMS+47 51 3.3k 5mo
[2026 update] A rising related-substance total over six months: degradation or method drift?
The question in the title: A rising related-substance total over six months: degradation or method drift? I will give what I have already checked below so nobody repeats it. Posting the method first, because…
CDASHKBSL+71 78 34k 5mo
Trifluoroacetate content and its consequences
Trifluoroacetate content and its consequences — setting out what I have, and where I think it stops being reliable. What changes if the standard account of trifluoroacetate content is wrong? I ask because I…
AIRDRVHFAV+123 134 31k 5mo
Aggregates and why a purity assay may miss them entirely
Aggregates and why a purity assay may miss them entirely Writing it up because I had to work it out twice and would rather nobody else did. I would like to disagree carefully with the settled view on…
RVIDSSVKFP+61 69 2.9k 6mo
Revisiting: Aggregates and why a purity assay may miss them entirely
Posting this under the heading it deserves: Revisiting: Aggregates and why a purity assay may miss them entirely Everything below is what sits behind that. I would like to disagree carefully with the settled…
LVNCOLNVMS+48 53 918 8mo
Particulates in a reconstituted solution: identifying the likely source
Posting this under the heading it deserves: Particulates in a reconstituted solution: identifying the likely source Everything below is what sits behind that. Something about particulates does not reconcile…
SCNECCYMRM+15 19 13k 9mo
Particulates in a reconstituted solution: identifying the likely source — what changed since
Particulates in a reconstituted solution: identifying the likely source — what changed since — setting out what I have, and where I think it stops being reliable. What changes if the standard account of…
GPMSCV 2 129 14mo
Coming back to: Oxidation pathways for methionine and tryptophan
Oxidation pathways for methionine and tryptophan Writing it up because I had to work it out twice and would rather nobody else did. Reading back through what has been written here about Oxidation pathways for…
YRFHKRZSCP+1 5 36k 15mo
Deamidation and the close-eluting pair it produces
Deamidation and the close-eluting pair it produces Writing it up because I had to work it out twice and would rather nobody else did. Something about deamidation does not reconcile and I would like a second…
IARMASPKA+33 37 46k 15mo
Follow-up: Attributing a new peak: degradation product or excipient?
Attributing a new peak: degradation product or excipient? I have a specific reason for asking rather than idle curiosity, and the context is below. A follow-up question about Attributing a new peak that I did…
KIABCSGV+15 19 671 17mo
Oxidation pathways for methionine and tryptophan
Posting this under the heading it deserves: Oxidation pathways for methionine and tryptophan Everything below is what sits behind that. Working notes on oxidation pathways for methionine rather than a…
GVQZILUCZC+58 63 1k 19mo