COA Quality Verifier

A Certificate of Analysis (COA) is the most important document for verifying peptide quality. Fake or inadequate COAs are common in the research market. Use this interactive checklist to determine whether a COA meets minimum standards.

Important Notice

This tool provides a heuristic assessment only. It cannot definitively prove a COA is genuine or that a peptide is safe. Always consult a qualified professional and independently verify testing data before use. No liability is accepted for decisions made based on this score.

Required Items

+10 points each

Red Flags

−15 points each

Quality Score

0/ 70
03570
Reject — Do Not Use This Product
Required items present0 / 7
Red flags detected0 / 8

Recommendations

  • Send a sample for independent third-party testing.
  • Request mass spectrometry data and molecular weight confirmation from the supplier.
  • Compare the HPLC chromatogram to the expected single-peak profile.
  • Check if the testing laboratory actually exists and is ISO 17025 accredited.
  • Demand endotoxin results before any injection.
  • Request a lot-specific COA — generic templates are not valid proof of quality.

Learn More

What is HPLC and why does purity matter?
High-performance liquid chromatography separates a peptide mixture into individual components. The largest peak represents your target peptide; smaller peaks are impurities (truncated sequences, side products, or contaminants). For research, ≥98% purity is the standard because even small impurities can confound experimental results or cause unwanted biological effects.
How to read a mass spec result
Mass spectrometry reports the mass-to-charge ratio (m/z) of ions. For a peptide COA, look for a major peak corresponding to the expected molecular weight (often reported as [M+H]+). The observed mass should be within ~1 Da of the theoretical mass. If the report shows multiple unexplained peaks or a mass that does not match, the sample may be incorrect or degraded.
Why endotoxin testing is safety-critical
Endotoxins (lipopolysaccharides from Gram-negative bacteria) can trigger severe immune reactions, including fever, hypotension, and septic shock. The Limulus Amebocyte Lysate (LAL) test measures endotoxin in Endotoxin Units per milligram (EU/mg). Injectable peptides should be ≤5 EU/mg for research; clinical use demands ≤0.5 EU/mg. Never inject a peptide without confirmed endotoxin data.
Third-party vs. self-issued COAs
A third-party COA is issued by an independent analytical laboratory with no financial stake in the sale. A self-issued COA is produced by the vendor itself. Self-issued documents carry inherent conflict of interest: the seller has every incentive to report favorable results. Always prioritize COAs from accredited, named independent labs (e.g., ISO 17025 accredited facilities).
How to verify a testing laboratory
1) Search the lab name online — it should have a professional website, address, and contact information. 2) Look for ISO 17025 or equivalent accreditation. 3) Call or email the lab and ask them to confirm they performed the specific test on the specific lot number. 4) Cross-check the reported methods (HPLC, MS, LAL) against the lab's stated capabilities. If any step fails, treat the COA as unverified.

Peptide-Specific Verification Notes

BPC-157

Expected MW ~1419.7 Da. Look for the acetate or arginine salt form on the COA.

TB-500

Expected MW ~4963 Da (Thymosin β4 fragment 17-23). Verify sequence Ac-SDKP or full TB-500.

GHK-Cu

Should show copper content (typically ~8-9% by weight) in addition to peptide identity.

Semaglutide

Should show correct salt form (usually acetate or free base) and confirm amidated C-terminus by MS.

Full Disclaimers

1. Not a guarantee of authenticity. This tool scores a COA based on the presence or absence of common data fields. A high score does not prove a COA is genuine, and a low score does not prove it is fake. Sophisticated counterfeiters can produce documents that pass superficial checks.

2. Not medical or legal advice. Nothing on this page constitutes medical advice, legal advice, or a recommendation to purchase, possess, or use any peptide. Always consult a licensed healthcare provider and comply with local laws.

3. No liability. We accept no liability for any loss, injury, or adverse outcome resulting from reliance on this tool, the scores it generates, or any peptide purchased based on its output.

4. Independent verification required. The only way to be certain of peptide identity and purity is to send a sample to an independent, accredited analytical laboratory for testing.

5. Research use only. Most peptides discussed are not approved by the FDA for human consumption or therapeutic use. They are sold for laboratory research purposes only.