Dr.MetabolicMD said:HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean: Purity %: Should be…
Same experience, arrived at from the opposite direction. Nothing to add that would improve it.
dave_SLC said:My vendor review relevant to certificates of analysis: ordered 4 times from my current compounder.
Third-party testing services for certificates of analysis besides Janoshik:
- Janoshik: Gold standard for peptide community, ~$145, 10-14 day turnaround
- Valitech: US-based, ISO 17025 accredited, ~$245
- Eurofins: Full pharmaceutical testing suite, more expensive but comprehensive
- ChemTox: Basic identity and purity testing, ~$115
Janoshik is the community standard but any ISO-accredited analytical lab can verify peptide identity and purity. The key is independence — don't rely solely on the vendor's own testing.
A narrower follow-up, since the general answer is now clear:
What did you change at the same time, and can you separate the two now?
Sigma-Aldrich — Research-Grade Standards
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Shop Reference StandardsDr.GutHealth said:Third-party testing services for certificates of analysis besides Janoshik: Janoshik: Gold standard for peptide community, ~$145, 10-14 day turnaround…
Reconstituted peptide stability data for certificates of analysis: I had Janoshik test my reconstituted vial at day 1, day 14, and day 28 stored in the refrigerator.
Day 1: 100.3% purity
Day 14: 99.3% purity
Day 28: 97.3% purity
Minimal degradation over 28 days when properly refrigerated. This confirms the standard 28-day beyond-use date is appropriate. Beyond 28 days, I'd reconstitute a fresh vial to be safe.