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coa

Page 26 of 33 · 771 questions tagged coa.

771 questions · sorted by votes · page 26 of 33

10 votes 5 answers7.3k views
Would you re-test tirzepatide after three weeks at 37 °C, or accept the original certificate?

The specifics, since they change the answer: tirzepatide · three weeks · 37 °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 juan_esquivel 14k · 3 months ago
10 votes 4 answers7k views
What does a 97.1% purity with a batch certificate attached let me conclude?

Setup, so nobody has to ask: 97.1% · batch certificate. I have read the primary source rather than the summary, which has left me with more questions. I understand…

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 siobhan_deasy 9.5k · 6 months ago
10 votes 4 answers6.3k views
How do I trace an SGN lot number back to a synthesis date?

This is my second independent submission on material from the same supplier. I would like to understand the steps well enough to explain them to someone else. 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…

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-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 eoin_mcgarry 18k · 3 months ago
10 votes5 answers5.1k views
What does a 503A pharmacy need to prepare semaglutide lawfully?

The pharmacy is accredited and I have verified that on the accreditor register. The figures are clear enough; the question is what they mean and what they do not. I…

pharmacy-503a
pharmacy-503a

Section 503A traditional compounding pharmacies specifically: patient-specific prescriptions, accreditation such as PCAB and ACHC, USP 797…

17 questions
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
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 a_lindgren 58k · 11 months ago
10 votes3 answers4.6k views
How many vials from a Homopeptide lot should I send for a sterility test?

For reference: Homopeptide · 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…

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 bac_or_bust 33k · 11 months ago
10 votes 3 answers4.6k views
What does a 97.9% purity with a batch certificate attached let me conclude?

Stated plainly: 97.9% · batch certificate. I have read the primary source rather than the summary, which has left me with more questions. I understand the headline. I…

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 kelvin_lam 7.6k · 2 months ago
10 votes5 answers2.6k views
How do I reconcile 95.2% from Medutest with 97.1% from the supplier?

Setup, so nobody has to ask: 95.2% · Medutest · 97.1%. I noticed this today and I have not touched anything since, in case the state is diagnostic. I have not…

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 mz_4113 101k · 3 months ago
10 votes 2 answers2.3k views
What does Janoshik verification of Qingdao Sigma Chemical actually cover?

What I have: Janoshik · Qingdao Sigma Chemical. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to…

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
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
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 meniscus_film 32k · 3 months ago
9 votes 5 answers29k views
What does a sterility test add for orforglipron that a purity figure does not?

Conditions: a sterility test · orforglipron. I want to know what the trade-off actually is rather than which option is fashionable. I would rather have a defensible…

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
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
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 valentina_rossi 9.7k · 2.2 years ago
9 votes 5 answers28k views
What does PeptideMeter verification of Hubei Jianxiang Bioscience actually cover?

Stated plainly: PeptideMeter · Hubei Jianxiang Bioscience. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I am…

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
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
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 cap_the_luer 14k · 2.1 years ago
9 votes 5 answers18k views
How does BCH compare to Nantong Guangyuan Chemical on documentation quality?

Setup, so nobody has to ask: BCH · Nantong Guangyuan Chemical. Both of these get recommended confidently by different people, which suggests neither is obviously…

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 tri_gly_ala 24k · 13 months ago
9 votes 5 answers16k views
What does 98.8% purity on a C8 column actually tell me about an oral semaglutide vial?

What I have: 98.8% · a C8 column · oral semaglutide. 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
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 Dr_Tomas_Kral 53k · 23 months ago
9 votes5 answers15k views
Has anyone independently verified a GGPeps survodutide batch COA?

The specifics, since they change the answer: GGPeps · survodutide. I would like to know whether this claim survives contact with evidence. If the answer is "nobody…

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
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 coldbox9 41k · 20 months ago
9 votes 5 answers13k views
Has anyone independently verified an SSA semaglutide batch COA?

Setup, so nobody has to ask: SSA · semaglutide. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has tested that", 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 Dr_Nadia_Farsi 104k · 18 months ago
9 votes0 answers13k views
Has anyone independently verified a JEEP retatrutide batch COA?

The case in front of me: JEEP · retatrutide. I would rather be corrected now than propagate something wrong. I am specifically not interested in a testimonial; I am…

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
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 Dr_Tomas_Kral 53k · 2.0 years ago
9 votes 4 answers12k views
Would you re-test oral semaglutide after three weeks at minus 80 °C, or accept the original certificate?

The particulars: oral semaglutide · three weeks · minus 80 °C. I am at the decision point and I would rather think it through than improvise. I would rather spend…

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
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 Dr_Nadia_Farsi 104k · 2.0 years ago
9 votes 5 answers11k views
How do I reconcile 98.4% from PeptideMeter with 95.2% from the supplier?

The particulars: 98.4% · PeptideMeter · 95.2%. An unexpected observation, and I would like a differential rather than reassurance. The conditions were within what I…

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 ivo_paunovic 16k · 18 months ago
9 votes 3 answers9.6k views
What does Medutest verification of GL Biochem (Shanghai) actually cover?

The specifics, since they change the answer: Medutest · GL Biochem (Shanghai). I would like help reading this properly rather than being told what conclusion to…

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
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
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 lucia_marchetti 19k · 8 months ago
9 votes 5 answers8.2k views
What would you ask Wuhan Wansheng Biotechnology before a first order that they cannot fake?

I have kept every message, invoice and document, which I gather is the useful habit. I can find plenty of assertions about this and almost no reasoning, which is…

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 mg_per_ml 15k · 5 months ago
9 votes 5 answers6.1k views
How do I verify that a COA actually came from the laboratory named on it?

I have the report as a PDF with the chromatogram on page two, so I can quote specifics. I would rather be corrected now than propagate something wrong. 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…

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
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 vial_five 12k · 2 months ago
9 votes5 answers5.2k views
What does a lot-specific certificate on a JEEP report change about how I read it?

Setup, so nobody has to ask: lot-specific certificate · JEEP. I have read the primary source rather than the summary, which has left me with more questions. I…

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 lane_transit 60k · 18 days ago
9 votes0 answers3.7k views
What would you ask Tianjin Finder Chemical before a first order that they cannot fake?

This is a first order from this supplier, so I have no track record to reason from. This is a procedural question rather than a theoretical one, and I would like 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
asked by w_okoye 43k · 6 months ago
9 votes 3 answers3.4k views
What does 97.6% purity on a C4 column actually tell me about a dulaglutide vial?

Concretely: 97.6% · a C4 column · dulaglutide. 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…

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
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 mass_shift_18 9.7k · 7 months ago
9 votes 2 answers1.9k views
How do I write up a PeptideMeter result on tirzepatide so it is useful to others?

What I am working with: PeptideMeter · tirzepatide. I have done this once and I suspect I got away with it rather than got it right. For context: I keep records of…

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
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 Dr_Signe_Baldursdottir 29k · 3 months ago