Intersection · Analytics × peak integration

Analytics topics tagged peak integration

Topics in Analytics carrying the tag peak integration. Where the integrator drew the baseline, and how much that changes the number.

26 topics

Topic	Participants	Replies	Views	Activity
What a reversed-phase purity number actually is HPLC system suitability data table peak integration Solved The question in the title: What a reversed-phase purity number actually is I will give what I have already checked below so nobody repeats it. I would like to understand what this number means before I repeat…	+87	101	27k	4h
Follow-up: Comparing two chromatograms from different laboratories, properly gradient method system suitability HPLC peak integration Comparing two chromatograms from different laboratories, properly — setting out what I have, and where I think it stops being reliable. I would like to understand what this number means before I repeat it…	+62	67	12k	9h
Why 99.2% and 97.8% on the same lot can both be correct system suitability peak integration gradient method data table Solved Why 99.2% and 97.8% on the same lot can both be correct 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…	+16	20	3.1k	11h
Shoulders, tangent skims, and defensible integration peak integration UV & DAD detection HPLC gradient method Posting this under the heading it deserves: Shoulders, tangent skims, and defensible integration Everything below is what sits behind that. Setting out an integration problem with the actual figures, because…	+16	20	11k	13h
About the HPLC & UHPLC category HPLC peak integration gradient method Pinned Wiki Reversed-phase separations, gradients, columns, integration, and reading a chromatogram properly. This post is a community wiki: any member at trust level 3 or above can edit it, and every edit is recorded…		4	137	18h
System suitability injections: if they failed, the run did not happen — the long version gradient method UV & DAD detection system suitability peak integration System suitability injections: if they failed, the run did not happen — the long version — setting out what I have, and where I think it stops being reliable. A narrow question about System suitability…	+2	6	6.2k	1d
[2026 update] Why 99.2% and 97.8% on the same lot can both be correct UV & DAD detection system suitability peak integration gradient method Solved Why 99.2% and 97.8% on the same lot can both be correct — that is the question, and I have not found it answered plainly anywhere I have looked. I would like to understand what this number means before I…	+1	5	719	2d
[2026 update] Area percent versus weight percent: the confusion that causes most arguments gradient method UV & DAD detection peak integration data table On the subject in the title: Area percent versus weight percent: the confusion that causes most arguments Working notes rather than a conclusion. Proposing that Area percent versus weight percent deserves a…	+65	70	1.1k	16d
Resolution and tailing factor: real acceptance criteria HPLC gradient method peak integration system suitability Resolution and tailing factor: real acceptance criteria Writing it up because I had to work it out twice and would rather nobody else did. Asking about resolution and tailing factor on behalf of the question…		2	15k	1mo
Injection volume, overload, and peak distortion peak integration system suitability HPLC data table Solved Posting this under the heading it deserves: Injection volume, overload, and peak distortion Everything below is what sits behind that. I have spent a fortnight trying to pin injection volume down and I want…	+43	47	36k	2mo
Area percent versus weight percent: the confusion that causes most arguments system suitability UV & DAD detection HPLC data table Posting this under the heading it deserves: Area percent versus weight percent: the confusion that causes most arguments Everything below is what sits behind that. Proposing that area percent versus weight…	+10	14	2.1k	2mo
[2026 update] Reading a chromatogram someone posted without axes peak integration HPLC UV & DAD detection data table Posting this under the heading it deserves: Reading a chromatogram someone posted without axes Everything below is what sits behind that. Reading a chromatogram, from the point of view of someone who has read…		2	59	2mo
Shoulders, tangent skims, and defensible integration — the long version HPLC system suitability peak integration data table Shoulders, tangent skims, and defensible integration — the long version Writing it up because I had to work it out twice and would rather nobody else did. Setting out an integration problem with the actual…	+16	20	27k	3mo
Injection volume, overload, and peak distortion — one year on system suitability peak integration gradient method data table Under review Injection volume, overload, and peak distortion — one year on Writing it up because I had to work it out twice and would rather nobody else did. Posting a small dataset on Injection volume. It is mine, it is…	+4	8	1.2k	4mo
Comparing two chromatograms from different laboratories, properly peak integration system suitability UV & DAD detection gradient method Solved Closed Posting this under the heading it deserves: Comparing two chromatograms from different laboratories, properly Everything below is what sits behind that. I would like to understand what this number means…	+35	40	22k	7mo
Detection wavelength and why 214 nm and 280 nm disagree peak integration UV & DAD detection system suitability HPLC On the subject in the title: Detection wavelength and why 214 nm and 280 nm disagree Working notes rather than a conclusion. I would like to disagree carefully with the settled view on detection wavelength,…	+78	84	1.7k	8mo
Coming back to: Resolution and tailing factor: real acceptance criteria peak integration data table UV & DAD detection Posting this under the heading it deserves: Resolution and tailing factor: real acceptance criteria Everything below is what sits behind that. Reading back through what has been written here about Resolution…	+93	112	5.7k	9mo
Coming back to: Where the integrator drew the baseline, and how much it moved the number peak integration gradient method UV & DAD detection data table On the subject in the title: Where the integrator drew the baseline, and how much it moved the number Working notes rather than a conclusion. Posting the method first, because I know what the first three…	+20	24	2.7k	10mo
Revisiting: Why I ask for the gradient before I discuss the number UV & DAD detection data table peak integration system suitability Posting this under the heading it deserves: Revisiting: Why I ask for the gradient before I discuss the number Everything below is what sits behind that. I would like to understand what this number means…	+15	19	43k	10mo
Column chemistry choices for a 40-residue peptide gradient method system suitability HPLC peak integration Column chemistry choices for a 40-residue peptide — setting out what I have, and where I think it stops being reliable. Collecting what is known about column chemistry choices in one place, because it is…	+39	43	1.1k	10mo
System suitability injections: if they failed, the run did not happen peak integration HPLC data table gradient method 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. Proposing that system suitability injections…	+23	27	6k	11mo
Second pass at: What a reversed-phase purity number actually is peak integration UV & DAD detection system suitability On the subject in the title: Second pass at: What a reversed-phase purity number actually is Working notes rather than a conclusion. I would like to understand what this number means before I repeat it…		2	7.4k	11mo
Reading a chromatogram someone posted without axes HPLC UV & DAD detection gradient method data table Reading a chromatogram someone posted without axes — setting out what I have, and where I think it stops being reliable. Posting a small dataset on reading a chromatogram. It is mine, it is uncontrolled, and…	+47	55	9.4k	13mo
Carryover and the ghost peak from last week's standard data table UV & DAD detection peak integration system suitability On the subject in the title: Carryover and the ghost peak from last week's standard Working notes rather than a conclusion. What changes if the standard account of carryover is wrong? I ask because I have…	+80	92	16k	16mo
Coming back to: Column chemistry choices for a 40-residue peptide peak integration system suitability gradient method data table On the subject in the title: Column chemistry choices for a 40-residue peptide Working notes rather than a conclusion. Column chemistry choices — I have the observation and I do not trust my interpretation of…		2	43k	16mo
Gradient steepness and apparent purity: a worked comparison data table UV & DAD detection peak integration HPLC On the subject in the title: Gradient steepness and apparent purity: a worked comparison Working notes rather than a conclusion. I have spent a fortnight trying to pin gradient steepness and apparent purity…		2	51k	22mo

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