Peptide COA red flags: 8 signs of a recycled certificate

A COA is easy to produce and hard to verify. These are the patterns that separate a real release document from a template.

1. No batch number, or a batch that does not match the label

The certificate must tie to the physical lot. If the number differs from the vial label or invoice, the document proves nothing about what you received.

2. Purity without a chromatogram

A percentage alone is unverifiable. Real release data includes the trace, integration and impurity profile.

3. The same file across products

Identical layout is normal; identical peak retention times, dates and signatures across different compounds are not.

4. Methods described as "in-house" with no detail

Column, gradient and wavelength are not trade secrets — they are what makes a result reproducible.

5. No mass-spec identity

HPLC proves homogeneity, not identity. Without MS, "the right peak" could be the wrong molecule.

6. Water content marked "N/A"

Moisture affects stability and weighing. A serious release document reports it with a number and a method. What the methods measure, and why “loss on drying” is not the same result, is covered in measuring water content.

7. Certification logos with no numbers

ISO or GMP marks without a certificate number and issuing body cannot be verified. Treat them as decoration.

8. Results that are too clean

Real synthesis leaves minor peaks. A chromatogram with no visible impurities at all deserves a second look at the integration.

What to do

Ask for the raw chromatogram file, the MS spectrum and the batch record reference. A supplier with a real system answers in minutes; one without changes the subject.

Research use only.

Editor's take

A recycled certificate is rarely a clumsy forgery; it is usually a template with the name changed and the chromatogram left alone. The tell is not the layout — it is the absence of anything lot-specific.

Sources & evidence

Method validation: ICH Q2(R1) — ICH quality guidelines.
Specifications: ICH Q6B — same ICH page.
Water / particulates / endotoxin: USP <731>, <788>, <85> — USP.
Chinese Pharmacopoeia (ChP 2020) Part IV: chapters 0512, 0832, 0903, 1143 — cited by chapter number.

No laboratory testing was performed by the author for this guide; acceptance limits must come from your own specification.

Limitations

This guide describes methods and interpretation, not acceptance limits. Limits must come from your own specification and, where applicable, the relevant pharmacopoeial monograph. No testing was performed by the author for this page.