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content-assay

Page 14 of 19 · 438 questions tagged content-assay.

438 questions · sorted by votes · page 14 of 19

12 votes 5 answers7.4k views
Does aspartimide formation of oral semaglutide at 30 °C show up as a loss of content or of purity?

Concretely: aspartimide formation · oral semaglutide · 30 °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,…

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_Sara_Kuusela 46k · 6 months ago
12 votes1 answer7.1k views
Does deamidation of ecnoglutide at minus 20 °C show up as a loss of content or of purity?

For reference: deamidation · ecnoglutide · minus 20 °C. I understand the observation; what I do not understand is the mechanism behind it. I have read the two review…

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 gradient_slope 41k · 8 months ago
12 votes0 answers6.2k views
Why did two Homopeptide lots of tirzepatide differ on content assay?

The case in front of me: Homopeptide · tirzepatide. I think I have a problem. I am not yet sure whether it is a real problem or a measurement artefact. I want to know…

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 priya_menon 11k · 16 months ago
12 votes 1 answer5.4k views
Does deamidation of semaglutide at 40 °C show up as a loss of content or of purity?

The specifics, since they change the answer: deamidation · semaglutide · 40 °C. I understand the observation; what I do not understand is the mechanism behind it. I…

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_Elias_Weiss 46k · 3 months ago
12 votes 3 answers5k views
Why does compounded potency vary between pharmacies?

I would like to understand the process rather than be told to try harder. The empirical answer seems settled. The explanation does not. If the honest answer is that…

compounding
compounding

Compounded preparations: what a 503A and a 503B facility may legally prepare and when, base versus salt forms, beyond-use dating under USP…

61 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 p_mkhize 41k · 42 days ago
12 votes3 answers4.3k views
Would you accept 97.1% on oral semaglutide from QSC without a content assay?

Conditions: 97.1% · oral semaglutide · QSC. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I would like…

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 rukhsana_iqbal 14k · 44 days ago
12 votes 5 answers3.9k views
Why did two QSC lots of mazdutide differ on content assay?

What I am working with: QSC · mazdutide. I noticed this today and I have not touched anything since, in case the state is diagnostic. I have not discarded anything…

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 unit_math 13k · 26 days ago
12 votes 5 answers3.8k views
Why did two Homopeptide lots of oral semaglutide differ on content assay?

Concretely: Homopeptide · oral semaglutide. I think I have a problem. I am not yet sure whether it is a real problem or a measurement artefact. I want to know whether…

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 syringe_ninety 15k · 2 months ago
12 votes0 answers3.2k views
How much of the gross mass of a 30 mg orforglipron vial is actually peptide?

What I have: 30 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…

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 p_mkhize 41k · 3 months ago
12 votes4 answers2.1k views
Does racemisation of retatrutide at 2–8 °C show up as a loss of content or of purity?

What I have: racemisation · retatrutide · 2–8 °C. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would like to know…

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 ravi_pillai 16k · 2 months ago
11 votes 4 answers22k views
Does hydrolysis of retatrutide at 30 °C show up as a loss of content or of purity?

Details up front: hydrolysis · retatrutide · 30 °C. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware this may have a boring…

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 harriet_lonsdale 14k · 15 months ago
11 votes 4 answers19k views
Would you accept 96.4% on oral semaglutide from QSC without a content assay?

Concretely: 96.4% · oral semaglutide · QSC. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I would like…

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 ivo_paunovic 15k · 2.2 years ago
11 votes5 answers16k views
Why did two JEEP lots of retatrutide differ on content assay?

Details up front: JEEP · retatrutide. Before I write this off, I want to check whether it is a known failure mode. I have the lot number, the certificate and 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…

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 otto_brenner 19k · 11 months ago
11 votes5 answers13k views
What does a residual-solvent screen add for mazdutide that a purity figure does not?

What I am working with: a residual-solvent screen · mazdutide. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume 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
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 tri_gly_ala 48k · 23 months ago
11 votes5 answers13k views
Would you accept 97.9% on dulaglutide from SSA without a content assay?

Details up front: 97.9% · dulaglutide · 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…

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 dead_volume 49k · 17 months ago
11 votes5 answers12k views
Does dimerisation of mazdutide at 25 °C show up as a loss of content or of purity?

Setup, so nobody has to ask: dimerisation · mazdutide · 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 lane_transit 42k · 13 months ago
11 votes5 answers7.7k views
Which single measurement would I keep if I could only have one?

I am comparing a supplier certificate against an independent result on the same lot. The failure mode I am trying to avoid is making this decision emotionally. I have…

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
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 second_lot 11k · 5 months ago
11 votes0 answers6.2k views
Does retatrutide adsorb measurably to the vial wall at 5 mg/mL?

Stated plainly: retatrutide · 5 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, for the…

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 wren_calloway 14k · 8 months ago
11 votes5 answers5.7k views
Does oxidation of liraglutide at minus 80 °C show up as a loss of content or of purity?

Conditions: oxidation · liraglutide · minus 80 °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,…

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 retest_please 13k · 8 months ago
11 votes0 answers5.6k views
Does a large published testing history at CPC 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…

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 Dr_Fatima_Belkacem 52k · 21 months ago
11 votes 5 answers5.5k views
Would you accept 97.1% on dulaglutide from MKM without a content assay?

What I have: 97.1% · dulaglutide · MKM. 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 stopper_core 50k · 6 months ago
11 votes 3 answers4.6k views
Would you accept 99.1% on semaglutide from WWB without a content assay?

For reference: 99.1% · semaglutide · WWB. I am at the decision point and I would rather think it through than improvise. I would rather spend money on measurement…

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 ruaidhri_o_shea 51k · 7 months ago
11 votes0 answers3.3k views
What does "net peptide content" mean on a certificate?

I am comparing a supplier certificate against an independent result on the same lot. The figures are clear enough; the question is what they mean and what they do…

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
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 unit_math 13k · 40 days ago
11 votes0 answers2.4k views
Would you accept 99.1% on survodutide from KP without a content assay?

The particulars: 99.1% · survodutide · KP. 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…

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 coring_risk 17k · 2 months ago