Topic summary

Publishing an inconvenient result: a case study — the long version

Sourcing › Independent verification Janoshik Analytical PeptideMeter Medutest blind sampling

This is a generated summary. It shows the 9 most-liked posts from a topic of 75, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

f.petrovTL2 Moderator17 Oct 2025#12

c.inglethorpe, post #10: When results are inconclusive: if a testing service reports "insufficient to verify" on a documentation review, that is not a negative finding about the product. It means the documents did not contain enough to check. Go to post

Worth separating two things that post #8 runs together.

Janoshik Analytical: chromatographic purity and mass-spectrometric identity on submitted samples. Reports are issued with the analytical method stated and a chromatogram included. Submission is by mail.

24 likes in reply to #10 9mo

c.marchettiTL2 Moderator22 Oct 2025 · edited#16

On post #12 — agreed on the reasoning, with one qualification.

Medutest: combined purity and identity reporting. Appears throughout vendor documentation. Where a submission has been blind we note it because blind results are worth more than self-selected ones.

32 likes 9mo

f.piresTL2 Moderator31 Oct 2025#24

g.rasmussen, post #4: How to submit a sample: contact the service directly. They will provide instructions on vial type, quantity, labelling, shipping. Following their instructions exactly ensures results are interpretable. Go to post

Picking up post #21: that is the part I would want checked first.

Interpreting a result: a purity figure is one measurement on one vial on one day. Agreement across two services is much stronger. A single high number does not establish a pattern.

27 likes in reply to #4 9mo

p.mwangiTL2 Moderator9 Nov 2025#32

j.teixeira, post #20: Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had been repeating something I had not checked carefully enough. Go to post

Medutest: combined purity and identity reporting. Appears throughout vendor documentation. Where a submission has been blind we note it because blind results are worth more than self-selected ones.

29 likes in reply to #20 9mo

n.nybergTL2 Moderator16 Nov 2025#39

Service differences on vendor pages: Janoshik and Medutest results are measurements on vials. PeptideMeter verification records are assessments maintained over time. VendorInvestigate reviews are documentation assessments. We cite all four because they answer different questions.

28 likes 8mo

p.novotnyTL2Regular24 Nov 2025#48

y.asante, post #36: VendorInvestigate: documentation and supplier-practice review. Reviews paperwork rather than vials. Tells you something about a supplier's systems but says nothing about what is in a container. Go to post

post #47 answers the question as asked. The question underneath it is different.

24 likes in reply to #36 8mo

e.verhoevenTL2 Moderator28 Nov 2025#52

journalclub_wren, post #35: This follows post #32 rather than contradicting it. When results are inconclusive: if a testing service reports "insufficient to verify" on a documentation review, that is not a negative finding about the product. It means the documents did not contain enough to check. Go to post

How to submit a sample: contact the service directly. They will provide instructions on vial type, quantity, labelling, shipping. Following their instructions exactly ensures results are interpretable.

26 likes in reply to #35 8mo

OstrowskiTL2Member4 Dec 2025#59

post #58 answers the question as asked. The question underneath it is different.

PeptideMeter: purity analysis plus structured, dated supplier verification records. Produces both individual analytical results and verification records assessed over time rather than at a point in time.

25 likes 8mo

cohort_driftTL3Regular15 Dec 2025#71

For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.

26 likes 7mo

Read the full topic (75 posts)

This topic was referenced in

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