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content-assay

Page 3 of 20 · 476 questions tagged content-assay.

476 questions · sorted by votes · page 3 of 20

33 votes 4 answers15k views
Does orforglipron adsorb measurably to the vial wall at 3.33 mg/mL?

Setup, so nobody has to ask: orforglipron · 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
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 zeynep_arslan 16k · 20 months ago
32 votes 5 answers39k views
Does tirzepatide adsorb measurably to the vial wall at 4 mg/mL?

For reference: tirzepatide · 4 mg/mL. I would rather understand the derivation than memorise the outcome. Two people I asked gave two answers that differ by a factor…

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
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 ilaria_bertone 33k · 15 months ago
32 votes 5 answers36k views
What counter-ion should I expect on a GGPeps ecnoglutide lot?

Conditions: GGPeps · ecnoglutide. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is that I am being…

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 jana_horakova 10k · 2.1 years ago
32 votes5 answers32k views
How much of the gross mass of a 15 mg survodutide vial is actually peptide?

The particulars: 15 mg · survodutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator…

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
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 marta_szymanska 10k · 19 months ago
32 votes5 answers27k views
How do I check that two WWB lots of retatrutide agree on content assay?

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

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 rhian_prydderch 23k · 16 months ago
32 votes0 answers22k views
What is the point of a content assay if I already have a purity figure?

I have both a purity figure and a content figure, which is why the discrepancy is visible. I can predict the outcome but I cannot explain it, which means I will get…

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 juliette_farnese 13k · 14 months ago
32 votes 5 answers19k views
How much of the gross mass of a 2 mg orforglipron vial is actually peptide?

What I have: 2 mg · orforglipron. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method is what…

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 w_okoye 43k · 2.1 years ago
32 votes 5 answers17k views
Does a large published testing history at Homopeptide imply lot consistency?

I am comparing a supplier certificate against an independent result on the same lot. I want to know whether this is a real physical effect or an artefact of how it is…

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
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
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
asked by bufferline42 30k · 11 months ago
31 votes 5 answers43k views
Does oxidation of oral semaglutide at 30 °C show up as a loss of content or of purity?

Concretely: oxidation · oral semaglutide · 30 °C. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the…

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
oral-glp1
oral-glp1

Oral routes for GLP-1 receptor agonism: peptide formulations rescued by absorption enhancers such as SNAC, and true small molecules that need no…

219 questions
asked by birk_nordahl 16k · 2.1 years ago
31 votes3 answers43k views
Does a large published testing history at TFC imply lot consistency?

I am comparing a supplier certificate against an independent result on the same lot. This is one of those things that everyone repeats and nobody derives. This…

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
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
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
asked by ravi_pillai 12k · 2.1 years ago
31 votes 5 answers39k views
Would you accept 99.1% on oral semaglutide from WXT without a content assay?

Conditions: 99.1% · oral semaglutide · WXT. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow the plan I write…

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
oral-glp1
oral-glp1

Oral routes for GLP-1 receptor agonism: peptide formulations rescued by absorption enhancers such as SNAC, and true small molecules that need no…

219 questions
asked by lucia_marchetti 19k · 2.2 years ago
31 votes5 answers35k views
Does a large published testing history at QST imply lot consistency?

The method section is present, which is unusual enough that I want to make use of it. This is one of those things that everyone repeats and nobody derives. This…

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
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
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
asked by Dr_Idris_Coulibaly 33k · 23 months ago
31 votes 5 answers34k views
What counter-ion should I expect on a WXT mazdutide lot?

Concretely: WXT · mazdutide. I have read the primary source rather than the summary, which has left me with more questions. I understand the headline. I do not…

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
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 plunger_stop 13k · 2.0 years ago
31 votes 5 answers31k views
Does oxidation of tirzepatide at 4 °C show up as a loss of content or of purity?

Conditions: oxidation · tirzepatide · 4 °C. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the question is…

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 coring_risk 27k · 20 months ago
31 votes 2 answers28k views
Does retatrutide adsorb measurably to the vial wall at 20 mg/mL?

What I am working with: retatrutide · 20 mg/mL. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so far,…

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 tare_and_weigh 12k · 16 months ago
31 votes 5 answers23k views
Does oxidation of oral semaglutide at 25 °C show up as a loss of content or of purity?

The case in front of me: oxidation · oral semaglutide · 25 °C. I want to know whether this is a real physical effect or an artefact of how it is measured. What…

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
oral-glp1
oral-glp1

Oral routes for GLP-1 receptor agonism: peptide formulations rescued by absorption enhancers such as SNAC, and true small molecules that need no…

219 questions
asked by ben_akintola 10k · 21 months ago
31 votes3 answers21k views
Is an endotoxin test worth paying for on top of a purity figure for mazdutide?

Conditions: an endotoxin test · mazdutide. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

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
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 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 kofi_mensah 18k · 23 months ago
31 votes0 answers17k views
Would you accept 97.1% on cagrilintide from TFC without a content assay?

Stated plainly: 97.1% · cagrilintide · TFC. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

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
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by ben_akintola 10k · 20 months ago
31 votes 5 answers14k views
How do I check that two SSA lots of survodutide agree on content assay?

For reference: SSA · survodutide. Something has gone wrong and I would like to know how badly before I decide what to do. Nothing else in the setup changed, which is…

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
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 second_lot 9.4k · 13 months ago
31 votes 5 answers12k views
Would you accept 98.4% on liraglutide from BCH without a content assay?

The case in front of me: 98.4% · liraglutide · BCH. 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 void_volume 9.5k · 12 months ago
31 votes0 answers9.8k views
What is traceability, in practical terms, for a reference material?

This is my second independent submission on material from the same supplier. I can predict the outcome but I cannot explain it, which means I will get the next case…

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
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
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
asked by ten_mg_vial 31k · 18 months ago
30 votes 4 answers57k views
How do I check that two GL Biochem lots of survodutide agree on content assay?

The specifics, since they change the answer: GL Biochem · survodutide. An unexpected observation, and I would like a differential rather than reassurance. 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
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 mateo_iglesias 12k · 2.0 years ago
30 votes 5 answers54k views
Does cagrilintide adsorb measurably to the vial wall at 1 mg/mL?

Numbers first: cagrilintide · 1 mg/mL. 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…

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
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by bounty_hunter_q 15k · 2.0 years ago
30 votes 5 answers45k views
How many vials from an SGN lot should I send for a quantified content assay?

What I am working with: SGN · a quantified content assay. This should be a straightforward calculation and I keep getting two different answers. The numbers are…

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
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
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
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
asked by noor_alhassan 11k · 23 months ago