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coa

Page 13 of 32 · 749 questions tagged coa.

749 questions · sorted by votes · page 13 of 32

22 votes 5 answers14k views
What does a 98.2% purity with a method section attached let me conclude?

Conditions: 98.2% · method section. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics…

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
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by unit_math 13k · 5 months ago
22 votes 5 answers13k views
How do I reconcile 97.9% from Janoshik with 99.1% from the supplier?

What I have: 97.9% · Janoshik · 99.1%. I have a result I cannot explain, and I would rather diagnose it than guess. I have checked the obvious explanations and…

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
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
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 day_seven_trough 11k · 11 months ago
22 votes5 answers13k views
How do I reconcile 96.4% from Medutest with 97.1% from the supplier?

What I am working with: 96.4% · Medutest · 97.1%. This is not behaving the way I expected and I want to understand the discrepancy before I act on it. I have…

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
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
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 forty_units 14k · 10 months ago
22 votes 5 answers12k views
Has anyone independently verified an ERP cagrilintide batch COA?

What I am working with: ERP · cagrilintide. This is asserted often enough that I assumed it was established, and then I went looking for the source. I have searched…

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
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
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
asked by Dr_Signe_Baldursdottir 46k · 5 months ago
22 votes 2 answers12k views
Has anyone independently verified an SSA survodutide batch COA?

For reference: SSA · survodutide. Somebody stated this to me confidently and I would like to check it before repeating it. I would accept a well-reasoned negative…

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
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
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
asked by u100_marks 38k · 5 months ago
22 votes 5 answers11k views
How does HJ compare to Zhuhai Kerui Biotechnology on documentation quality?

The case in front of me: HJ · Zhuhai Kerui Biotechnology. These are treated as interchangeable and I do not think they are. If both are acceptable I would like to…

vendor-comparison
vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

351 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
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 two_two_micron 15k · 19 months ago
22 votes5 answers11k views
How do I read a mazdutide chromatogram from Janoshik beyond the headline number?

Details up front: mazdutide · Janoshik. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 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_Ingrid_Baumgartner 39k · 14 months ago
22 votes 5 answers9.7k views
What does a 97.1% purity with a method section attached let me conclude?

Conditions: 97.1% · method section. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics…

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
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by Dr_Ilse_Vandenberg 78k · 2 months ago
22 votes 3 answers8.9k views
Why does the same chromatogram give a different purity at 214 nm and at 280 nm?

A report I have includes traces at two wavelengths from the same injection, using a diode-array detector. The 214 nm trace integrates to 98.6% and the 280 nm trace to…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 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
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…

360 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…

162 questions
asked by anja_hellstrom 13k · 2.1 years ago
22 votes0 answers7.7k views
What should I make of a mazdutide certificate that has no purity figure?

What I have: mazdutide · purity figure. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to…

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
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
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
asked by tri_gly_ala 48k · 5 months ago
22 votes2 answers7.3k views
What does a Karl Fischer water content test add for liraglutide that a purity figure does not?

Concretely: a Karl Fischer water content test · liraglutide. These are treated as interchangeable and I do not think they are. If both are acceptable I would like to…

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 · 6 months ago
22 votes 4 answers4.9k views
How do I reconcile 97.9% from Medutest with 95.2% from the supplier?

Stated plainly: 97.9% · Medutest · 95.2%. I noticed this today and I have not touched anything since, in case the state is diagnostic. I have not discarded anything…

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
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
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 s_bhattacharya 42k · 4 months ago
22 votes4 answers4.3k views
What does 96.4% purity on a C8 column actually tell me about a tirzepatide vial?

What I have: 96.4% · a C8 column · tirzepatide. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 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 fiadh_cronin 14k · 3 months ago
21 votes 5 answers53k views
Has anyone independently verified a QYB semaglutide batch COA?

The particulars: QYB · semaglutide. Somebody stated this to me confidently and I would like to check it before repeating it. I would accept a well-reasoned negative…

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
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
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
asked by Dr_Idris_Coulibaly 40k · 2.2 years ago
21 votes 5 answers44k views
How does SSA compare to Qingdao Saber Technology on documentation quality?

The particulars: SSA · Qingdao Saber Technology. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments for each…

vendor-comparison
vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

351 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
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 · 2.2 years ago
21 votes 5 answers29k views
What does a date of analysis on a CPC report change about how I read it?

For reference: date of analysis · CPC. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is that I am…

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
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
asked by rukhsana_iqbal 14k · 18 months ago
21 votes 5 answers23k views
How do I reconcile 97.6% from PeptideMeter with 97.1% from the supplier?

The specifics, since they change the answer: 97.6% · PeptideMeter · 97.1%. An unexpected observation, and I would like a differential rather than reassurance. 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…

788 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
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 rae_oyelowo 21k · 12 months ago
21 votes5 answers22k views
What should I make of a liraglutide certificate that has no chromatogram?

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

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
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
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
asked by micron22 36k · 21 months ago
21 votes5 answers21k views
How many vials from a WXT lot should I send for peptide mapping?

What I am working with: WXT · peptide mapping. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude…

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
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
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
asked by lipid_panel_q 44k · 8 months ago
21 votes4 answers20k views
Has anyone independently verified a WWB retatrutide batch COA?

What I have: WWB · retatrutide. I would rather be corrected now than propagate something wrong. I am specifically not interested in a testimonial; I am interested in…

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
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
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
asked by dana_wexler 15k · 12 months ago
21 votes 5 answers19k views
What does peptide mapping add for survodutide that a purity figure does not?

For reference: peptide mapping · survodutide. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments for each and…

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 ekaterina_volk 16k · 7 months ago
21 votes5 answers18k views
What does a 97.6% purity with a lot-specific certificate attached let me conclude?

Numbers first: 97.6% · lot-specific certificate. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to…

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
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by Dr_Idris_Coulibaly 40k · 2.3 years ago
21 votes 5 answers18k views
What should I make of an oral semaglutide certificate that has no list of related substances?

The specifics, since they change the answer: oral semaglutide · list of related substances. I want to understand what this actually establishes, as opposed to what it…

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
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
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
asked by teodora_ilic 15k · 2.1 years ago
21 votes0 answers18k views
What accept/reject threshold would you set for mazdutide before seeing the result?

I have both a purity figure and a content figure, which is why the discrepancy is visible. I would rather over-plan the first cycle and simplify later. I am prepared…

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
harm-reduction
harm-reduction

Reducing avoidable risk where a decision has already been made: independent verification before use, sterility practice, dose arithmetic checked…

445 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_Nadia_Farsi 90k · 12 months ago