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content-assay

Page 9 of 20 · 476 questions tagged content-assay.

476 questions · sorted by votes · page 9 of 20

21 votes2 answers36k views
How much of the gross mass of an 8 mg orforglipron vial is actually peptide?

Numbers first: 8 mg · orforglipron. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would rather…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
water-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 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
orforglipron
orforglipron

A non-peptide, orally bioavailable small-molecule GLP-1 receptor agonist studied in the ATTAIN programme. It is not a peptide, which changes…

219 questions
asked by ines_delacruz 16k · 2.1 years ago
21 votes 5 answers34k views
How do I check that two SGN lots of retatrutide agree on content assay?

Concretely: SGN · retatrutide. I have a result I cannot explain, and I would rather diagnose it than guess. I have checked the obvious explanations and eliminated the…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
retatrutide
retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

251 questions
asked by pip_okonjo 13k · 20 months ago
21 votes 3 answers29k views
What counter-ion should I expect on an MKM survodutide lot?

Concretely: MKM · survodutide. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I am reasonably comfortable with…

acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
purity
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 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by ayo_fadipe 9.4k · 19 months ago
21 votes2 answers22k views
Does mazdutide adsorb measurably to the vial wall at 6.67 mg/mL?

Details up front: mazdutide · 6.67 mg/mL. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by zainab_mustafa 21k · 2.0 years ago
21 votes 4 answers19k views
How does reference-standard error propagate into a retatrutide content figure?

The method section is present, which is unusual enough that I want to make use of it. The units are where I keep going wrong, so please be explicit about them. I have…

reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
retatrutide
retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

251 questions
asked by Dr_Wren_Halliday 19k · 11 months ago
21 votes 5 answers19k views
What does peptide mapping add for survodutide that a purity figure does not?

Setup, so nobody has to ask: peptide mapping · survodutide. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
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 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by ekaterina_volk 21k · 7 months ago
21 votes 4 answers18k views
Would you accept 98.2% on ecnoglutide from SWB without a content assay?

The particulars: 98.2% · ecnoglutide · SWB. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with explicit stopping…

purity
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 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
asked by fibre_or_fragment 13k · 2.3 years ago
21 votes5 answers17k views
Does dimerisation of a GLP-1 receptor agonist at minus 80 °C show up as a loss of content or of purity?

Stated plainly: dimerisation · a GLP-1 receptor agonist · minus 80 °C. I keep seeing this stated as a fact with no explanation attached, and unexplained facts make me…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
asked by gradient_slope 46k · 8 months ago
21 votes 5 answers16k views
Is a sterility test worth paying for on top of a purity figure for dulaglutide?

For reference: a sterility test · dulaglutide. This is a planning question. I know what my options are; I do not know how to weigh them. What I want is the minimum…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
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 questions
asked by amara_nwachukwu 20k · 12 months ago
21 votes 4 answers14k views
What counter-ion should I expect on a QST liraglutide lot?

The specifics, since they change the answer: QST · liraglutide. I would like to know the limits of what can be inferred from this. What I am trying to avoid is…

acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
purity
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 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by two_point_four 8.9k · 4 months ago
21 votes 2 answers13k views
Does fibrillation of survodutide at 2–8 °C show up as a loss of content or of purity?

For reference: fibrillation · survodutide · 2–8 °C. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. I have…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by bufferline42 30k · 23 months ago
21 votes5 answers12k views
How does reference-standard error propagate into a dulaglutide content figure?

I am comparing a supplier certificate against an independent result on the same lot. I have worked this out and I would like someone to find the error, because I…

reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
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 questions
asked by noor_alhassan 11k · 3 months ago
21 votes 5 answers11k views
How does reference-standard error propagate into a GLP-1 receptor agonist content figure?

I have the report as a PDF with the chromatogram on page two, so I can quote specifics. I can do the algebra. I am not confident about the conversion factors. If…

reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
asked by ravi_pillai 12k · 10 months ago
21 votes0 answers9.7k views
Would you accept 98.2% on liraglutide from ERP without a content assay?

The case in front of me: 98.2% · liraglutide · ERP. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow the plan…

purity
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 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by shear_at_the_front 17k · 10 months ago
21 votes5 answers8.4k views
How much of the gross mass of a 40 mg tirzepatide vial is actually peptide?

The case in front of me: 40 mg · tirzepatide. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
water-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 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
asked by fibre_or_fragment 13k · 2 months ago
21 votes0 answers7.1k views
Would you accept 98.2% on mazdutide from QST without a content assay?

Stated plainly: 98.2% · mazdutide · QST. I am trying to build something sustainable rather than something thorough that I will abandon. I have already decided the…

purity
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 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by Dr_Jonas_Halvorsen 28k · 10 months ago
21 votes 1 answer7k views
What counter-ion should I expect on an MKM ecnoglutide lot?

The particulars: MKM · ecnoglutide. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I am reasonably comfortable…

acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
purity
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 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
asked by drawn_and_capped 12k · 6 months ago
21 votes 4 answers6.9k views
What makes something a "certified reference material", and why is my content result only as good as the standard?

Every explanation of quantitative HPLC I have read says the result is traceable to the reference standard, and then moves on as though that settles it. I want to open…

reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
purity
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 questions
asked by lukas_sedlacek 16k · 16 months ago
21 votes 5 answers6.5k views
Is a residual-solvent screen worth paying for on top of a purity figure for mazdutide?

For reference: a residual-solvent screen · mazdutide. I am trying to build something sustainable rather than something thorough that I will abandon. I have already…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
residual-solvent
residual-solvent

Solvents left behind by synthesis and purification - acetonitrile, TFA, DMF, DCM - their ICH limits, how they are measured by headspace GC, and…

14 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by cap_the_luer 14k · 2 months ago
21 votes0 answers6k views
Does retatrutide adsorb measurably to the vial wall at 3.33 mg/mL?

Setup, so nobody has to ask: retatrutide · 3.33 mg/mL. I have worked this out and I would like someone to find the error, because I suspect there is one. My working…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
retatrutide
retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

251 questions
asked by grainne_ahearn 50k · 3 months ago
20 votes 5 answers24k views
Does aspartimide formation of tirzepatide at 37 °C show up as a loss of content or of purity?

Conditions: aspartimide formation · tirzepatide · 37 °C. This is one of those things that everyone repeats and nobody derives. This matters practically, not just…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
asked by anders_vestby 8.5k · 16 months ago
20 votes5 answers23k views
Does fibrillation of semaglutide at room temperature show up as a loss of content or of purity?

Setup, so nobody has to ask: fibrillation · semaglutide · room temperature. I would like the mechanism, because I want to be able to reason about the cases nobody has…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

470 questions
asked by hana_petrikova 10k · 11 months ago
20 votes 5 answers22k views
How much of the gross mass of a 20 mg mazdutide vial is actually peptide?

Stated plainly: 20 mg · mazdutide. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude and it seems…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
water-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 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by olu_babatunde 6.2k · 20 months ago
20 votes0 answers22k views
Why does my content assay disagree with the label by more than purity would allow?

The method section is present, which is unusual enough that I want to make use of it. I noticed this today and I have not touched anything since, in case the state is…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
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 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
asked by pieter_maas 14k · 2.2 years ago