TrialNerd_Beth said:My HPLC chromatogram analysis for certificates of analysis — I sent my batch to Janoshik and here's what the results showed: Main peak retention time:…
I tested my certificates of analysis batch through Janoshik — 97.6% purity. That's within acceptable range for compounded peptides. Turnaround was 10 business days.
The test costs ~$120 but gives you actual HPLC chromatography data plus mass spec confirmation. For the peace of mind alone, it's worth every penny. I test every new batch from a new vendor.
Following on from TrialNerd_Beth — and this may be the naive question:
Did your prescriber agree with that reading, and if not what was their objection?
PeptideChemSF said:I tested my certificates of analysis batch through Janoshik — 97.6% purity.
Community-verified vendors for certificates of analysis: I maintain a spreadsheet of Janoshik-verified test results submitted by community members. Across 47 submitted tests:
- 75% tested at ≥98% purity
- 18% tested at 95-98% purity
- 7% tested at <95% purity (concerning)
The vendors with consistently high purity results are listed in the Vendor Directory. We update monthly based on new community submissions.
Sigma-Aldrich — Research-Grade Standards
Certified reference materials, analytical reagents, and research-grade standards for peptide verification. Trusted by laboratories worldwide.
Shop Reference StandardsPeptideChemSF said:I tested my certificates of analysis batch through Janoshik — 97.6% purity.
Right, and the exception is worth naming rather than left implied, because the exception is where people get into trouble.
PeptideChemSF said:I tested my certificates of analysis batch through Janoshik — 97.6% purity.
This is exactly what I could not find anywhere else.