Sourcing · Independent verification · continued

Chain of custody for a sample you posted yourself — one year on posts 31–33

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

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

g.bakkenTL2 Moderator18 Jul 2026#31

On post #27 — agreed on the reasoning, with one qualification.

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.

8 likes 10d

asking_properlyTL1Member22 Jul 2026#32

post #31 answers the question as asked. The question underneath it is different.

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.

2 likes 5d

y.eriksenTL2 Moderator27 Jul 2026#33

h.ferrari, post #2: 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

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.

0 likes in reply to #2 15h

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