roxy_nash said:

Mass spectrometry confirmation for certificates of analysis: beyond HPLC purity, mass spec tells you the molecule's exact molecular weight.

Adding a me-too, because a thread of one person's experience is not much use.

SleepDoc_PDX said:

I tested my certificates of analysis batch through Janoshik — 97.3% purity.

COA red flags for certificates of analysis — here's what to look for when reviewing a Certificate of Analysis:

• No HPLC data: If there's no chromatography graph, it's not a real COA
• Exact 100% purity: Suspicious — real testing always shows slight variation
• No batch number: Can't trace back to specific production
• No endotoxin testing: For injectables, this is essential
• Template looks like it was made in Word: Professional labs have standardized formats

I have seen fake COAs that are literally photoshopped. Always verify independently if possible.

One thing that is still open after SleepDoc_PDX’s answer:

What did you change at the same time, and can you separate the two now?

PharmacoVig_BOS said:

COA red flags for certificates of analysis — here's what to look for when reviewing a Certificate of Analysis: No HPLC data: If there's no…

HPLC results interpretation for certificates of analysis: when you get your Janoshik report back, here's what the numbers mean:

• Purity %: Should be >97%. Below 95% is concerning.
• Retention time: Should match reference standard for the peptide
• Related substances: Degradation products should be <2% total
• Single impurity: No individual impurity should exceed 1%

My last batch: 99.4% purity, 0.0% total related substances. Clean chromatogram with single sharp peak at expected retention time. Exactly what you want to see.

Moderator note: reminder that nothing in this thread is medical advice, and that clinical claims need a source.