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content-assay

Page 18 of 19 · 438 questions tagged content-assay.

438 questions · sorted by votes · page 18 of 19

4 votes0 answers4.2k views
Does fibrillation of semaglutide at 25 °C show up as a loss of content or of purity?

The specifics, since they change the answer: fibrillation · semaglutide · 25 °C. I would like the mechanism, because I want to be able to reason about the cases…

peptide-stability
peptide-stability

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

832 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…

438 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…

788 questions
asked by fibre_or_fragment 12k · 2.1 years ago
4 votes 2 answers3.3k views
Does dimerisation of mazdutide at 4 °C show up as a loss of content or of purity?

Setup, so nobody has to ask: dimerisation · mazdutide · 4 °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,…

832 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…

438 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…

788 questions
asked by Dr_Otto_Lindqvist 38k · 12 months ago
4 votes 5 answers3k views
What counter-ion should I expect on an SGN orforglipron lot?

What I have: SGN · orforglipron. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

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…

87 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…

788 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…

438 questions
asked by rae_oyelowo 21k · 3 months ago
4 votes 1 answer1.9k views
What counter-ion should I expect on a WWB retatrutide lot?

Numbers first: WWB · retatrutide. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

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…

87 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…

788 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…

438 questions
asked by valentina_rossi 16k · 4 months ago
3 votes 5 answers9.4k views
Would you accept 99.1% on ecnoglutide from WWB without a content assay?

The specifics, since they change the answer: 99.1% · ecnoglutide · WWB. I would like to define my thresholds before I have a result, for obvious reasons. I want a…

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…

788 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by Dr_Lena_Ostrowska 42k · 8 months ago
3 votes 5 answers8.3k views
Would you accept 98.4% on retatrutide from SSA without a content assay?

What I have: 98.4% · retatrutide · SSA. I would rather over-plan the first cycle and simplify later. I am prepared to do the work if someone can tell me which work…

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…

788 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by gunnar_isaksen 16k · 12 months ago
3 votes 5 answers4.2k views
Does ecnoglutide adsorb measurably to the vial wall at 3.33 mg/mL?

Concretely: ecnoglutide · 3.33 mg/mL. Please show the division. I want to check my own against yours. I would like the general form as well as the specific number, so…

peptide-stability
peptide-stability

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

832 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…

438 questions
storage
storage

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

646 questions
asked by threadlock7 14k · 2 months ago
3 votes5 answers3.9k views
Does liraglutide adsorb measurably to the vial wall at 2.5 mg/mL?

For reference: liraglutide · 2.5 mg/mL. I would rather understand the derivation than memorise the outcome. Two people I asked gave two answers that differ by a…

peptide-stability
peptide-stability

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

832 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…

438 questions
storage
storage

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

646 questions
asked by birk_nordahl 20k · 8 months ago
3 votes 5 answers2.6k views
Why did two WXT lots of a GLP-1 receptor agonist differ on content assay?

Stated plainly: WXT · a GLP-1 receptor agonist. I noticed this today and I have not touched anything since, in case the state is diagnostic. I have not discarded…

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…

865 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by plunger_stop 18k · 42 days ago
3 votes0 answers1.9k views
What counter-ion should I expect on a TFC oral semaglutide lot?

The case in front of me: TFC · oral semaglutide. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the…

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…

87 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…

788 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…

438 questions
asked by void_volume 13k · 5 months ago
3 votes0 answers413 views
Does a large published testing history at WXT imply lot consistency?

I am comparing a supplier certificate against an independent result on the same lot. I keep seeing this stated as a fact with no explanation attached, and unexplained…

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…

865 questions
vendor-vetting
vendor-vetting

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

436 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…

438 questions
asked by birk_nordahl 20k · 6 days ago
2 votes5 answers20k views
What counter-ion should I expect on an HJ tirzepatide lot?

Conditions: HJ · tirzepatide. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics change the…

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…

87 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…

788 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…

438 questions
asked by Dr_Bram_Verhoeven 85k · 23 months ago
2 votes 5 answers17k views
How do I know a laboratory is quantifying against a real standard?

The method section is present, which is unusual enough that I want to make use of it. The claim is plausible, which is exactly why I want to check it. I am able to…

reference-standard
reference-standard

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

179 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…

438 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…

749 questions
asked by coldbox9 13k · 2.1 years ago
2 votes 5 answers17k views
Would you accept 97.1% on tirzepatide from BCH without a content assay?

Conditions: 97.1% · tirzepatide · BCH. 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 down,…

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…

788 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by ahmed_zerouali 19k · 17 months ago
2 votes 5 answers16k views
Would you accept 99.1% on cagrilintide from CPC without a content assay?

Setup, so nobody has to ask: 99.1% · cagrilintide · CPC. I am trying to build something sustainable rather than something thorough that I will abandon. I have already…

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…

788 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by nominal_ten 14k · 17 months ago
2 votes 5 answers14k views
What does an endotoxin test add for cagrilintide that a purity figure does not?

Setup, so nobody has to ask: an endotoxin test · cagrilintide. Both of these get recommended confidently by different people, which suggests neither is obviously…

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…

438 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…

788 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…

749 questions
asked by Dr_Bram_Verhoeven 85k · 15 months ago
2 votes 5 answers13k views
Does aggregation of a GLP-1 receptor agonist at room temperature show up as a loss of content or of purity?

Setup, so nobody has to ask: aggregation · a GLP-1 receptor agonist · room temperature. The empirical answer seems settled. The explanation does not. If the honest…

peptide-stability
peptide-stability

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

832 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…

438 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…

788 questions
asked by fibre_or_fragment 12k · 19 months ago
2 votes 5 answers11k views
Would you accept 96.4% on cagrilintide from HJ without a content assay?

What I am working with: 96.4% · cagrilintide · HJ. I am trying to build something sustainable rather than something thorough that I will abandon. I have already…

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…

788 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by dana_wexler 15k · 13 months ago
2 votes 5 answers10k views
What counter-ion should I expect on a BCH mazdutide lot?

What I am working with: BCH · mazdutide. I would like help reading this properly rather than being told what conclusion to reach. I have the full report including the…

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…

87 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…

788 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…

438 questions
asked by j_wierzbicki 45k · 16 months ago
2 votes 5 answers9.7k views
Does aggregation of cagrilintide at 25 °C show up as a loss of content or of purity?

Setup, so nobody has to ask: aggregation · cagrilintide · 25 °C. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody…

peptide-stability
peptide-stability

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

832 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…

438 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…

788 questions
asked by nominal_ten 14k · 20 months ago
2 votes 5 answers7.7k views
Would you accept 99.1% on retatrutide from QYB without a content assay?

What I have: 99.1% · retatrutide · QYB. 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 viable…

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…

788 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…

438 questions
vendor-vetting
vendor-vetting

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

436 questions
asked by tabular_nums 47k · 7 months ago
2 votes 4 answers7.7k views
Does dimerisation of cagrilintide at 25 °C show up as a loss of content or of purity?

What I am working with: dimerisation · cagrilintide · 25 °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,…

832 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…

438 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…

788 questions
asked by lipid_panel_q 44k · 19 months ago
2 votes 5 answers7.3k views
Is a quantified content assay worth paying for on top of a purity figure for tirzepatide?

Conditions: a quantified content assay · tirzepatide. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I…

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…

438 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…

865 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,…

261 questions
lc-ms
lc-ms

Liquid chromatography coupled to mass spectrometry: separation and identification in one run, and the method of choice when you need to know not…

14 questions
asked by k_szabo 45k · 11 months ago
2 votes 5 answers5.4k views
How much of the gross mass of a 20 mg cagrilintide vial is actually peptide?

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

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…

438 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…

39 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…

87 questions
asked by Dr_Ravi_Selvarajah 42k · 13 months ago