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coa

Page 19 of 33 · 771 questions tagged coa.

771 questions · sorted by votes · page 19 of 33

17 votes 5 answers7.8k views
Has anyone independently verified a CPC oral semaglutide batch COA?

Conditions: CPC · oral semaglutide. I want to know whether there is evidence behind this or only repetition. I have checked the obvious registries and monographs…

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
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 fib4_reader 24k · 3 months ago
17 votes5 answers7.6k views
What should I make of a cagrilintide documentation package that has no lot-specific certificate?

Setup, so nobody has to ask: cagrilintide · lot-specific certificate. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not…

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
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 Dr_Lena_Ostrowska 38k · 10 months ago
17 votes0 answers6.4k views
Why does compounded dulaglutide potency vary between pharmacies?

The pharmacy is accredited and I have verified that on the accreditor register. The empirical answer seems settled. The explanation does not. If the honest answer is…

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
dulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

200 questions
asked by halvard_ness 69k · 5 months ago
17 votes0 answers5.6k views
What does a 98.8% purity with a lot-specific certificate attached let me conclude?

Details up front: 98.8% · lot-specific certificate. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear…

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 Dr_Malik_Osei 19k · 3 months ago
17 votes 3 answers4.6k views
How do I read a sequence coverage map, and why is 100% coverage sometimes worthless?

I received a mapping report on tirzepatide. It states "sequence coverage: 100%" in bold at the top, and then the fragment table has exactly two entries in it.…

peptide-mapping
peptide-mapping

Enzymatic digestion followed by LC-MS/MS to confirm sequence rather than just mass. The method that catches a scrambled sequence or a D-amino-acid…

103 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…

10 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
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
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 a_lindgren 58k · 9 months ago
17 votes 5 answers4.4k views
What does a list of related substances on an SSA report change about how I read it?

Conditions: list of related substances · SSA. 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 anders_vestby 8.5k · 4 months ago
17 votes0 answers4k views
Has anyone independently verified a BCH a GLP-1 receptor agonist batch COA?

What I am working with: BCH · a GLP-1 receptor agonist. This has the shape of a fact but I cannot find its origin. What I found instead were three secondary sources…

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
asked by nils_karlberg 9.4k · 7 months ago
17 votes 1 answer3.4k views
Would you re-test tirzepatide after three weeks at 30 °C, or accept the original certificate?

The specifics, since they change the answer: tirzepatide · three weeks · 30 °C. I am at the decision point and I would rather think it through than improvise. I would…

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
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 claudia_ferrante 22k · 6 months ago
16 votes 5 answers27k views
Would you re-test dulaglutide after eight weeks at minus 80 °C, or accept the original certificate?

Stated plainly: dulaglutide · eight weeks · minus 80 °C. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight,…

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
dulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

200 questions
asked by nynke_dekker 9.4k · 15 months ago
16 votes 5 answers24k views
What accept/reject threshold would you set for a GLP-1 receptor agonist before seeing the result?

This is my second independent submission on material from the same supplier. This is a planning question. I know what my options are; I do not know how to weigh them.…

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
asked by anja_hellstrom 13k · 18 months ago
16 votes 5 answers22k views
Has anyone independently verified a GL Biochem semaglutide batch COA?

The specifics, since they change the answer: GL Biochem · semaglutide. Somebody stated this to me confidently and I would like to check it before repeating it. I…

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
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 plunger_stop 13k · 13 months ago
16 votes 5 answers21k views
What does 98.4% purity on a C8 column actually tell me about a tirzepatide vial?

Numbers first: 98.4% · a C8 column · tirzepatide. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone…

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
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 lipid_panel_q 36k · 14 months ago
16 votes5 answers20k views
What does a 96.8% purity with a chromatogram attached let me conclude?

For reference: 96.8% · chromatogram. 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…

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 Dr_Ravi_Selvarajah 35k · 9 months ago
16 votes 5 answers19k views
Has anyone independently verified an SGN orforglipron batch COA?

Setup, so nobody has to ask: SGN · orforglipron. I am asking for verification rather than opinion, ideally with something I can read myself. It is possible the…

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
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 charge_state_3 16k · 12 months ago
16 votes 2 answers17k views
How do I decide whether a batch is worth testing at all?

This is my second independent submission on material from the same supplier. I would like to define my thresholds before I have a result, for obvious reasons. I want…

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
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 jo_vandeberg 23k · 14 months ago
16 votes5 answers16k views
How do I reconcile 96.4% from Medutest with 98.4% from the supplier?

What I am working with: 96.4% · Medutest · 98.4%. 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 bea_castellanos 24k · 7 months ago
16 votes 5 answers15k views
How do I reconcile 96.8% from PeptideMeter with 99.1% from the supplier?

The particulars: 96.8% · PeptideMeter · 99.1%. Something has gone wrong and I would like to know how badly before I decide what to do. Nothing else in the setup…

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
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
asked by tare_weight 60k · 18 months ago
16 votes 5 answers15k views
How does QSC compare to Xi’an Mokemei Biotechnology on documentation quality?

Concretely: QSC · Xi’an Mokemei Biotechnology. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can obtain either…

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 rhian_prydderch 23k · 16 months ago
16 votes 2 answers14k views
Would you re-test retatrutide after eight weeks at 30 °C, or accept the original certificate?

Setup, so nobody has to ask: retatrutide · eight weeks · 30 °C. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not…

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
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 coldpack_88 50k · 10 months ago
16 votes 2 answers12k views
How do I read an oral semaglutide chromatogram from PeptideMeter beyond the headline number?

The case in front of me: oral semaglutide · PeptideMeter. I want to understand what this actually establishes, as opposed to what it is being used to imply. My…

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
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
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
asked by valentina_rossi 9.7k · 13 months ago
16 votes3 answers8.5k views
How does QST compare to Guangzhou JEEP Biotechnology on documentation quality?

Details up front: QST · Guangzhou JEEP Biotechnology. These are treated as interchangeable and I do not think they are. If both are acceptable I would like to know…

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 dmitri_savchuk 27k · 8 months ago
16 votes 3 answers7.7k views
How do I reconcile 96.8% from VendorInvestigate with 99.4% from the supplier?

Concretely: 96.8% · VendorInvestigate · 99.4%. 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…

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 ayo_fadipe 9.4k · 6 months ago
16 votes5 answers7.5k views
What would you ask ChinaPeptides (QYAOBIO) before a first order that they cannot fake?

I have kept every message, invoice and document, which I gather is the useful habit. I have read the obvious sources and they disagree with each other, so I would…

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
asked by samir_bennani 15k · 10 months ago
16 votes0 answers7.4k views
Has anyone independently verified an FGP mazdutide batch COA?

What I am working with: FGP · mazdutide. This has the shape of a fact but I cannot find its origin. What I found instead were three secondary sources all citing each…

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
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 Dr_Jonas_Halvorsen 28k · 16 months ago