Topic summary

How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ

Sourcing › Independent verification blind sampling PeptideMeter Medutest third-party testing Janoshik Analytical

This is a generated summary. It shows the 9 most-liked posts from a topic of 131, 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.

citation_peakTL3Regular4 May 2025#45

resistance_first, post #25: 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

Coming back to post #43, because the follow-up matters more than the original answer.

Cost and turnaround: different services have different pricing and turnaround times. Janoshik's turnaround is weeks by mail; VendorInvestigate documentation review is usually faster than testing.

32 likes in reply to #25 15mo

v.baptistaTL2 Moderator7 May 2025#61

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.

29 likes 15mo

ar.petrovTL2 Moderator9 May 2025#70

r.petrov, post #19: 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. 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.

28 likes in reply to #19 15mo

IsaksenTL3Regular10 May 2025#75

owen.brady, post #58: I read post #56 twice before replying, because I had assumed the opposite. Blind sampling: submitting without the laboratory or seller knowing the source removes the two easiest ways for a result to be shaped: selective submission and selective reporting. The extra effort is worth it. 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.

31 likes in reply to #58 15mo

g.ekstromTL2 Moderator11 May 2025 · edited#81

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.

30 likes 15mo

s.roosTL2 Moderator13 May 2025#87

Worth separating two things that post #83 runs together.

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.

31 likes 15mo

s.poulsenTL3Regular13 May 2025#90

Picking up post #87: that is the part I would want checked first.

Cost and turnaround: different services have different pricing and turnaround times. Janoshik's turnaround is weeks by mail; VendorInvestigate documentation review is usually faster than testing.

29 likes 15mo

batchlogTL3Regular15 May 2025#98

Two things before anyone answers the substance.

First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound.

30 likes 14mo

ms_hollowayTL4Mass spectrometrist19 May 2025#118

post #117 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.

32 likes 14mo

Read the full topic (131 posts)

This topic was referenced in

Chain of custody for a sample you posted yourselfSourcing › Independent verification · 2 replies

Suggested topics

Topic	Participants	Replies	Views	Activity
Blind submission and why it changes minds — the long version Sourcing › Independent verification Medutest third-party testing Janoshik Analytical Posting this under the heading it deserves: Blind submission and why it changes minds — the long version Everything below is what sits behind that. Structured report rather than an opinion, following the…	+98	113	18k	2mo
Choosing which test to pay for, given a fixed budget — does this still hold? Sourcing › Independent verification PeptideMeter blind sampling Janoshik Analytical VendorInvestigate Choosing which test to pay for, given a fixed budget — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below. I would like to talk about documentation…	+35	39	755	20mo
Chain of custody for a sample you posted yourself Sourcing › Independent verification PeptideMeter third-party testing Janoshik Analytical blind sampling Chain of custody for a sample you posted yourself Writing it up because I had to work it out twice and would rather nobody else did. A logistics question, since the answers here are usually better than…		2	7.3k	5h
Second pass at: Submitting a sample: the process end to end Sourcing › Independent verification Janoshik Analytical PeptideMeter Medutest blind sampling Solved Second pass at: Submitting a sample: the process end to end Writing it up because I had to work it out twice and would rather nobody else did. A logistics question, since the answers here are usually better…	+12	16	41k	4mo
Turnaround times and what they mean for a decision Sourcing › Independent verification PeptideMeter Medutest Janoshik Analytical VendorInvestigate Turnaround times and what they mean for a decision Writing it up because I had to work it out twice and would rather nobody else did. A logistics question, since the answers here are usually better than…		4	29k	3mo

Related topics — sharing the tags blind sampling, PeptideMeter, Medutest

Topic	Participants	Replies	Views	Activity
Documenting a supplier's response to a discrepancy — does this still hold? Sourcing › Vendor reports certificate of analysis third-party testing batch & lot numbers Documenting a supplier's response to a discrepancy — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below. Structured report rather than an opinion,…	+47	52	58k	16mo
Reporting a discrepancy without making an allegation Sourcing › Vendor reports batch & lot numbers disputed documentation quality certificate of analysis On the subject in the title: Reporting a discrepancy without making an allegation Working notes rather than a conclusion. Structured report rather than an opinion, following the format the maintainers asked…	+79	89	1k	22mo
Can a home kit substitute for a laboratory report? A careful no Analytics › Home & field testing third-party testing documentation quality LOD & LOQ ELISA Solved Asking directly, because I could not find a straight answer: Can a home kit substitute for a laboratory report? A careful no I would like to understand what this number means before I repeat it anywhere. A…	+122	131	1.7k	5mo
Revisiting: The report format the maintainers ask for, and why each field is there Sourcing › Vendor reports batch & lot numbers Janoshik Analytical documentation quality third-party testing Posting this under the heading it deserves: Revisiting: The report format the maintainers ask for, and why each field is there Everything below is what sits behind that. Structured report rather than an…	+100	108	57k	1d
Why quantitation is the hard part, not detection Analytics › Home & field testing LOD & LOQ third-party testing ELISA Why quantitation is the hard part, not detection I have a specific reason for asking rather than idle curiosity, and the context is below. Posting the method first, because I know what the first three replies…	+11	15	27k	12mo