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medutest

Medu Laboratories, one of four independent testing and verification services referenced throughout this site. Use this tag for its methods, its report format, and comparisons of its results against other laboratories on the same batch.

126 questions · sorted by votes · page 1 of 6

41 votes5 answers41k views
Is a 98.2% result from Janoshik comparable to 97.9% from Medu Laboratories?

What I have: 98.2% · Janoshik · 97.9% · Medu Laboratories. I have used one of these for a while and I am considering switching, which requires a reason. What I care about is…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 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
medutest
medutest

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

126 questions
asked by swab_and_wait 13k · 2.3 years ago
40 votes0 answers61k views
Is a 98.4% result from VendorInvestigator comparable to 97.6% from Medu Laboratories?

The case in front of me: 98.4% · VendorInvestigator · 97.6% · Medu Laboratories. These are treated as interchangeable and I do not think they are. If both are acceptable 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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
vendor-investigate
vendor-investigate

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

113 questions
medutest
medutest

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

126 questions
asked by dmitri_savchuk 27k · 2.3 years ago
40 votes 5 answers60k views
What does Medu Laboratories verification of Shanghai Sigma-Audley actually cover?

What I have: Medu Laboratories · Shanghai Sigma-Audley. I have read the primary source rather than the summary, which has left me with more questions. I understand the…

vendor-investigate
vendor-investigate

VendorInvestigator, 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

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

126 questions
asked by ravenna_pace 14k · 2.2 years ago
40 votes 5 answers27k views
How do I reconcile 95.2% from Medu Laboratories with 99.4% from the supplier?

What I am working with: 95.2% · Medu Laboratories · 99.4%. 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

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

126 questions
asked by bridget_nyathi 12k · 22 months ago
40 votes 4 answers23k views
How do PeptideDetective and VendorInvestigator compare on the same retatrutide batch?

What I am working with: PeptideDetective · VendorInvestigator · retatrutide. I would like the axes of comparison first and the recommendation second. I have tried the…

janoshik
janoshik

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

139 questions
medutest
medutest

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

126 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
peptidemeter
peptidemeter

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

107 questions
vendor-investigate
vendor-investigate

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

113 questions
asked by retest_please 9.7k · 20 months ago
39 votes 5 answers62k views
Is a 99.4% result from Janoshik comparable to 98.2% from Medu Laboratories?

Numbers first: 99.4% · Janoshik · 98.2% · Medu Laboratories. I want to know what the trade-off actually is rather than which option is fashionable. I would rather have a…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 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
medutest
medutest

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

126 questions
asked by rune_thoresen 16k · 21 months ago
39 votes 5 answers47k views
Is a 97.6% result from PeptideDetective comparable to 98.8% from Medu Laboratories?

The specifics, since they change the answer: 97.6% · PeptideDetective · 98.8% · Medu Laboratories. I am trying to choose between two options that are usually discussed as though…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
peptidemeter
peptidemeter

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

107 questions
medutest
medutest

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

126 questions
asked by t_oyelaran 79k · 2.2 years ago
38 votes 5 answers57k views
Is a 96.8% result from Medu Laboratories comparable to 97.9% from PeptideDetective?

What I am working with: 96.8% · Medu Laboratories · 97.9% · PeptideDetective. Both of these get recommended confidently by different people, which suggests neither is obviously…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
medutest
medutest

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

126 questions
peptidemeter
peptidemeter

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

107 questions
asked by ahmed_zerouali 15k · 2.0 years ago
38 votes0 answers29k views
Is a 97.9% result from VendorInvestigator comparable to 99.4% from Medu Laboratories?

Concretely: 97.9% · VendorInvestigator · 99.4% · Medu Laboratories. These are treated as interchangeable and I do not think they are. If both are acceptable I would like 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…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
vendor-investigate
vendor-investigate

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

113 questions
medutest
medutest

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

126 questions
asked by nine_point_nine 60k · 2.1 years ago
37 votes 4 answers39k views
Why would Medu Laboratories report 96.8% where the supplier certificate says something higher?

What I have: Medu Laboratories · 96.8%. 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 date, and 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
hplc
hplc

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

503 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
medutest
medutest

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

126 questions
asked by mala_venkatesh 22k · 2.3 years ago
36 votes 5 answers34k views
How do Janoshik and Medu Laboratories compare on the same ecnoglutide batch?

What I have: Janoshik · Medu Laboratories · ecnoglutide. Both of these get recommended confidently by different people, which suggests neither is obviously right. My…

janoshik
janoshik

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

139 questions
medutest
medutest

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

126 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
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
asked by dana_wexler 11k · 18 months ago
35 votes 5 answers36k views
How would I detect deamidation in an ecnoglutide vial without sending it to Medu Laboratories?

Concretely: deamidation · ecnoglutide · Medu Laboratories. I have read the obvious sources and they disagree with each other, so I would rather ask people who have actually…

vial-inspection
vial-inspection

What you can learn by looking: cake morphology, meniscus films, fibres versus stopper fragments versus true particulates, clarity after…

66 questions
peptide-stability
peptide-stability

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

908 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
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
medutest
medutest

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

126 questions
asked by mg_per_ml 15k · 23 months ago
34 votes 5 answers46k views
Is a 97.9% result from Medu Laboratories comparable to 98.8% from Janoshik?

Setup, so nobody has to ask: 97.9% · Medu Laboratories · 98.8% · Janoshik. Both of these get recommended confidently by different people, which suggests neither is obviously…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
medutest
medutest

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

126 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 ayo_fadipe 9.4k · 18 months ago
34 votes0 answers42k views
Does Medu Laboratories test the vial or accept the vendor’s sample?

The method section is present, which is unusual enough that I want to make use of it. This has the shape of a fact but I cannot find its origin. What I found instead…

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
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

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

126 questions
asked by s_kalniete 57k · 21 months ago
34 votes 5 answers29k views
How do I reconcile 98.4% from Medu Laboratories with 96.8% from the supplier?

What I am working with: 98.4% · Medu Laboratories · 96.8%. I noticed this today and I have not touched anything since, in case the state is diagnostic. I have not discarded…

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

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

126 questions
asked by n_takahashi 29k · 13 months ago
34 votes5 answers25k views
How do I reconcile 98.8% from Medu Laboratories with 98.4% from the supplier?

Stated plainly: 98.8% · Medu Laboratories · 98.4%. 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…

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

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

126 questions
asked by teodora_ilic 17k · 22 months ago
34 votes5 answers13k views
Why would Medu Laboratories report 98.4% where the supplier certificate says something higher?

Details up front: Medu Laboratories · 98.4%. 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 date,…

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
hplc
hplc

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

503 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
medutest
medutest

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

126 questions
asked by jonas_ekstrom 12k · 14 months ago
33 votes5 answers25k views
How would I detect deamidation in a semaglutide vial without sending it to Medu Laboratories?

The particulars: deamidation · semaglutide · Medu Laboratories. I have read the obvious sources and they disagree with each other, so I would rather ask people who have…

vial-inspection
vial-inspection

What you can learn by looking: cake morphology, meniscus films, fibres versus stopper fragments versus true particulates, clarity after…

66 questions
peptide-stability
peptide-stability

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

908 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
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
medutest
medutest

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

126 questions
asked by petra_hovland 35k · 17 months ago
33 votes 5 answers21k views
What has Medu Laboratories published on WWB lots in the last year?

Stated plainly: Medu Laboratories · WWB. I would like help reading this properly rather than being told what conclusion to reach. I have the full report including the method…

vendor-investigate
vendor-investigate

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

113 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-comparison
vendor-comparison

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

388 questions
medutest
medutest

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

126 questions
asked by fibre_or_fragment 13k · 12 months ago
32 votes5 answers35k views
How do I reconcile 99.4% from Medu Laboratories with 96.8% from the supplier?

Stated plainly: 99.4% · Medu Laboratories · 96.8%. This is not behaving the way I expected and I want to understand the discrepancy before I act on it. I have photographed 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
medutest
medutest

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

126 questions
asked by u100_marks 52k · 18 months ago
32 votes0 answers23k views
Is a 99.4% result from Medu Laboratories comparable to 96.4% from PeptideDetective?

Stated plainly: 99.4% · Medu Laboratories · 96.4% · PeptideDetective. Both of these get recommended confidently by different people, which suggests neither is obviously right. My…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
medutest
medutest

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

126 questions
peptidemeter
peptidemeter

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

107 questions
asked by anouk_desmet 16k · 18 months ago
32 votes 5 answers15k views
How do PeptideDetective and VendorInvestigator compare on the same dulaglutide batch?

Stated plainly: PeptideDetective · VendorInvestigator · dulaglutide. These are treated as interchangeable and I do not think they are. If both are acceptable I would like…

janoshik
janoshik

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

139 questions
medutest
medutest

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

126 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
peptidemeter
peptidemeter

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

107 questions
vendor-investigate
vendor-investigate

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

113 questions
asked by triple_agonist_q 57k · 13 months ago
31 votes 5 answers26k views
Is a 96.4% result from Janoshik comparable to 98.8% from Medu Laboratories?

Numbers first: 96.4% · Janoshik · 98.8% · Medu Laboratories. I have used one of these for a while and I am considering switching, which requires a reason. What I care about is…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 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
medutest
medutest

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

126 questions
asked by oona_kekkonen 13k · 16 months ago
31 votes 5 answers20k views
Is a 97.6% result from Medu Laboratories comparable to 98.4% from Janoshik?

What I am working with: 97.6% · Medu Laboratories · 98.4% · Janoshik. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can…

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
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
medutest
medutest

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

126 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 kirsi_lahtinen 25k · 12 months ago
Sponsored

Janoshik Analytical - Independent Third-Party Testing

HPLC purity, identity confirmation and quantified content on the vial you actually hold. Reports arrive with the chromatogram attached, not just a number.

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Founded 1998. ISO 9001 and cGMP certified, 1,500+ staff and 200+ patents. The synthesis house behind a great many of the vials that get sent out for testing - batch-specific documentation with every order.

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