The Peptide CommonsEst. May 2024
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Tags · Technique

HPLC

High-performance liquid chromatography, the workhorse purity method.

48 topics 16 solved Synonyms: uhplc, rp-hplc Group: Technique

Related in this group: LC-MS · high-resolution MS · MALDI-TOF · UV & DAD detection · peak integration · system suitability · gradient method · water content · amino acid analysis · ELISA · endotoxin testing · sterility testing

48 topics · page 2 of 2

TopicParticipantsRepliesViewsActivity
Detection wavelength and why 214 nm and 280 nm disagree
On the subject in the title: Detection wavelength and why 214 nm and 280 nm disagree Working notes rather than a conclusion. Posting the method first, because I know what the first three replies will…
BWZVGFFEDI+78 84 1.7k 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. Posting the method first, because I know what the…
SCNECCYMRM+15 19 13k 9mo
Theoretical plates: useful number or ritual?
Theoretical plates: useful number or ritual? I have a specific reason for asking rather than idle curiosity, and the context is below. I would like to understand what this number means before I repeat it…
MPALAV 2 284 9mo
Column chemistry choices for a 40-residue peptide
Column chemistry choices for a 40-residue peptide — setting out what I have, and where I think it stops being reliable. Posting the method first, because I know what the first three replies will otherwise be.…
SRDWZVGLCV+39 43 1.1k 10mo
System suitability injections: if they failed, the run did not happen
Posting this under the heading it deserves: System suitability injections: if they failed, the run did not happen Everything below is what sits behind that. A documentation question rather than an analytical…
KKCELLTNK+23 27 6k 11mo
Reading a chromatogram someone posted without axes
Reading a chromatogram someone posted without axes — setting out what I have, and where I think it stops being reliable. A documentation question rather than an analytical one. I have a certificate in front…
AZCMDDVVT+47 55 9.4k 13mo
Area percent versus weight percent: the confusion that causes most arguments — what changed since
Area percent versus weight percent: the confusion that causes most arguments — what changed since Writing it up because I had to work it out twice and would rather nobody else did. Posting the method first,…
VBSADMRLEN+30 34 40k 13mo
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. Posting the method first, because I know what…
GPMSCV 2 129 14mo
Residual solvents and scavengers: what is looked for
On the subject in the title: Residual solvents and scavengers: what is looked for Working notes rather than a conclusion. Posting the method first, because I know what the first three replies will otherwise…
DOEVABKPLG+19 23 39k 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. Working through the identity arithmetic and I would like it checked.…
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. I would like to understand what this number means before I repeat it…
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. Posting the method first, because I know what the first…
KIABCSGV+15 19 671 17mo
Attributing a new peak: degradation product or excipient?
Asking directly, because I could not find a straight answer: Attributing a new peak: degradation product or excipient? Posting the method first, because I know what the first three replies will otherwise be.…
SHOWM 2 15k 18mo
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 through the identity arithmetic and I would like it checked.…
GVQZILUCZC+58 63 1k 19mo
Why I ask for the gradient before I discuss the number
The question in the title: Why I ask for the gradient before I discuss the number I will give what I have already checked below so nobody repeats it. I would like to understand what this number means before I…
GPSFCNNDHK+35 39 4.9k 20mo
Follow-up: Trifluoroacetate content and its consequences
On the subject in the title: Trifluoroacetate content and its consequences Working notes rather than a conclusion. Posting the method first, because I know what the first three replies will otherwise be.…
AVABAZDTRG+12 16 5.7k 21mo
Gradient steepness and apparent purity: a worked comparison
On the subject in the title: Gradient steepness and apparent purity: a worked comparison Working notes rather than a conclusion. A documentation question rather than an analytical one. I have a certificate in…
POLFTI 2 51k 22mo
A rising related-substance total over six months: degradation or method drift?
Asking directly, because I could not find a straight answer: A rising related-substance total over six months: degradation or method drift? Posting the method first, because I know what the first three…
PBDAVGDVS+37 42 37k 23mo