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mass-spec

Page 3 of 3 · 52 questions tagged mass-spec.

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52 questions · sorted by votes · page 3 of 3

3 votes5 answers1.4k views
Dulaglutide as an Fc fusion — what changes analytically?

This matters because it predicts what a related molecule should do. These are treated as interchangeable and I do not think they are. If both are acceptable I would…

dulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

200 questionsmass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 questionspurity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questionsasked by eighty_six_hours 20k · 40 days ago
1 vote 4 answers5.2k views
How do I compute the +3 charge state m/z for a peptide of 4731.3 Da?

What I am working with: +3 · 4731.3 Da. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude and it…

mass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 questionsdosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questionspurity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questionsasked by tadhg_o_riordan 7.7k · 6 months ago
1 vote2 answers4.5k views
How do I compute the +5 charge state m/z for a peptide of 3751.0 Da?

Concretely: +5 · 3751.0 Da. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as well as the value…

mass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 questionsdosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questionspurity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questionsasked by k_szabo 27k · 8 months ago
1 vote0 answers1.4k views
Would a Karl Fischer water content test distinguish deamidation from a synthesis impurity in dulaglutide?

Conditions: a Karl Fischer water content test · deamidation · dulaglutide. I would like the axes of comparison first and the recommendation second. I have tried the…

peptide-mapping
peptide-mapping

Enzymatic digestion followed by LC-MS/MS to confirm sequence rather than just mass. The method that catches a scrambled sequence or a D-amino-acid…

103 questionspurity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questionsmass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 questionswater-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questionsdulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

200 questionsasked by mira_sundqvist 7.1k · 10 months ago