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coa

Page 12 of 33 · 771 questions tagged coa.

771 questions · sorted by votes · page 12 of 33

24 votes0 answers19k views
Is identity confirmation by mass spectrometry on one vial from a twenty-person split enough for the whole split?

The specifics, since they change the answer: identity confirmation by mass spectrometry · a twenty-person split. I would like to define my thresholds before I have a…

group-buy
group-buy

Pooled purchasing: how the economics work, what trust structure a pool needs, splitting a single tested lot, and the failure modes when the…

41 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
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
mass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 questions
asked by jonas_ekstrom 12k · 20 months ago
24 votes0 answers17k views
How do I reconcile 98.4% from Janoshik with 98.2% from the supplier?

Numbers first: 98.4% · Janoshik · 98.2%. 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…

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
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
janoshik
janoshik

Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content…

139 questions
asked by rae_oyelowo 17k · 17 months ago
24 votes 5 answers16k views
How do I write up a Janoshik result on a GLP-1 receptor agonist so it is useful to others?

What I am working with: Janoshik · a GLP-1 receptor agonist. This is a procedural question rather than a theoretical one, and I would like the procedure rather than…

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
harm-reduction
harm-reduction

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

472 questions
janoshik
janoshik

Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content…

139 questions
asked by second_lot 9.4k · 5 months ago
24 votes 4 answers16k views
How do I read an orforglipron chromatogram from Medutest beyond the headline number?

Setup, so nobody has to ask: orforglipron · Medutest. I would like help reading this properly rather than being told what conclusion to reach. I have the full report…

hplc
hplc

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

503 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
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
medutest
medutest

Medutest, one of four independent testing and verification services referenced throughout this site. Use this tag for its methods, its report…

126 questions
asked by leah_ferrers 12k · 8 months ago
24 votes5 answers15k views
Why does compounded cagrilintide potency vary between pharmacies?

Costs, fees and monitoring all included, I am trying to compare like with like. I can predict the outcome but I cannot explain it, which means I will get the next…

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…

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
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 thermal_mass 13k · 7 months ago
24 votes 5 answers14k views
Would you re-test mazdutide after six weeks at room temperature, or accept the original certificate?

What I am working with: mazdutide · six weeks · room temperature. This is a planning question. I know what my options are; I do not know how to weigh them. What I…

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
peptide-stability
peptide-stability

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

908 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
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 oona_kekkonen 13k · 10 months ago
24 votes 5 answers14k views
Has anyone independently verified a TFC liraglutide batch COA?

Details up front: TFC · liraglutide. The claim is plausible, which is exactly why I want to check it. I am able to read a paper if someone points me at one. Can…

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
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
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 jonas_ekstrom 12k · 8 months ago
24 votes 5 answers11k views
What does a 98.2% purity with a date of analysis attached let me conclude?

Concretely: 98.2% · date of analysis. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a single result,…

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
hplc
hplc

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

503 questions
asked by leonid_marchuk 19k · 18 months ago
24 votes2 answers11k views
What does a sampling plan on an FGP report change about how I read it?

Details up front: sampling plan · FGP. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

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
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
asked by siobhan_deasy 9.5k · 23 months ago
24 votes 5 answers11k views
Why does compounded semaglutide potency vary between pharmacies?

I would like to understand the process rather than be told to try harder. I want to know whether this is a real physical effect or an artefact of how it is measured.…

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…

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
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 threadlock7 19k · 3 months ago
24 votes3 answers8.8k views
On a COA, what is the difference between "peptide content", "net peptide" and "gross weight"?

I have a COA in front of me with all of the following on it, and I cannot work out which of these numbers is the one I care about: Appearance: white lyophilised…

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
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
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
asked by Dr_Elias_Weiss 25k · 13 months ago
24 votes5 answers8.1k views
Is a lot-specific certificate from SWB sufficient basis to skip independent testing?

For reference: lot-specific certificate · SWB. I am trying to build something sustainable rather than something thorough that I will abandon. I have already decided…

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
harm-reduction
harm-reduction

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

472 questions
asked by orla_ferriter 89k · 8 months ago
24 votes5 answers6k views
How do I reconcile 99.1% from VendorInvestigate with 96.8% from the supplier?

The case in front of me: 99.1% · VendorInvestigate · 96.8%. I have two candidate explanations and no way to distinguish them. The same procedure has worked without…

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
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
vendor-investigate
vendor-investigate

VendorInvestigate, an independent vendor review and verification service. Use this tag for questions about its verification criteria, what a…

113 questions
asked by ravenna_pace 14k · 5 months ago
24 votes0 answers4.5k views
What does a list of related substances on an MKM report change about how I read it?

Conditions: list of related substances · MKM. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the…

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
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
asked by felix_araya 6.8k · 5 months ago
23 votes 5 answers48k views
What should I make of a survodutide documentation package that has no date of analysis?

Setup, so nobody has to ask: survodutide · date of analysis. The figures are clear enough; the question is what they mean and what they do not. I can supply the…

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
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
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
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 mass_shift_18 9.7k · 2.1 years ago
23 votes5 answers43k views
How many vials from a CPC lot should I send for a sterility test?

What I have: CPC · a sterility test. 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…

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
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
asked by ines_brandt 113k · 23 months ago
23 votes 5 answers34k views
How does MKM compare to Qingdao Saber Technology on documentation quality?

What I have: MKM · 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 and…

vendor-comparison
vendor-comparison

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

388 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
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
asked by zeynep_arslan 16k · 14 months ago
23 votes5 answers33k views
How does Homopeptide compare to Shanghai Wibson Biotechnology on documentation quality?

Details up front: Homopeptide · Shanghai Wibson Biotechnology. I would like the axes of comparison first and the recommendation second. I have tried the first option…

vendor-comparison
vendor-comparison

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

388 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
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
asked by j_wierzbicki 69k · 2.1 years ago
23 votes 5 answers32k views
How do I write up a PeptideMeter result on oral semaglutide so it is useful to others?

What I am working with: PeptideMeter · oral semaglutide. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have already made…

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
harm-reduction
harm-reduction

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

472 questions
peptidemeter
peptidemeter

PeptideMeter, an independent peptide analytics and vendor-rating service. Use this tag for its published datasets, its rating methodology, and how…

107 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 m_haraldsen 21k · 17 months ago
23 votes 4 answers26k views
What does a quantified content assay add for liraglutide that a purity figure does not?

The specifics, since they change the answer: a quantified content assay · liraglutide. I would like the axes of comparison first and the recommendation second. I have…

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
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 cake_collapsed 14k · 2.4 years ago
23 votes 5 answers21k views
Which of the canon vendors publish lot-specific documentation?

The lane and the lead time matter as much as the material for what I am doing. I have the document in front of me and I can read the numbers. What I cannot do is…

vendor-comparison
vendor-comparison

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

388 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
asked by eighty_six_hours 20k · 12 months ago
23 votes0 answers18k views
What accept/reject threshold would you set for retatrutide before seeing the result?

The method section is present, which is unusual enough that I want to make use of it. I am trying to build something sustainable rather than something thorough that I…

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
harm-reduction
harm-reduction

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

472 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
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 seamus_brady 15k · 11 months ago
23 votes 2 answers12k views
How do I reconcile 98.2% from Medutest with 96.4% from the supplier?

What I am working with: 98.2% · Medutest · 96.4%. 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…

833 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
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
medutest
medutest

Medutest, one of four independent testing and verification services referenced throughout this site. Use this tag for its methods, its report…

126 questions
asked by net_peptide 12k · 11 months ago
23 votes 5 answers12k views
How do I reconcile 96.4% from Janoshik with 98.8% from the supplier?

What I have: 96.4% · Janoshik · 98.8%. 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…

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
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
janoshik
janoshik

Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content…

139 questions
asked by klara_novotna 19k · 9 months ago