Third-Party Testing & Certificates of Analysis
Every peptide sold by NoProp Peptides undergoes independent third-party testing before it reaches our catalog. This is not optional, not available “upon request,” and not performed in-house. An independent analytical laboratory tests every production batch using two complementary methods.
Testing Methods
HPLC Purity Analysis
High-Performance Liquid Chromatography (HPLC) separates the peptide sample into its individual components, producing a chromatogram that shows the target peptide peak versus any impurities. Our minimum acceptable purity is 99.0%. Batches below this threshold are rejected regardless of cost — a 98.5% pure batch introduces variables that compromise research data.
Mass Spectrometry (ESI-MS)
Electrospray Ionization Mass Spectrometry confirms the molecular weight of the synthesized peptide matches the expected value for the target compound. This verifies you received the correct peptide — not a mislabeled or truncated sequence. The observed mass must fall within ±1 Da of the theoretical molecular weight.
What a COA Includes
Every Certificate of Analysis shipped with your order contains:
- Product identification: Peptide name, sequence, batch/lot number
- HPLC chromatogram: Visual purity profile with percentage
- Mass spectrometry data: Observed vs. theoretical molecular weight
- Appearance: Physical description (lyophilized powder, color)
- Laboratory information: Independent lab name and testing date
Why Independent Testing Matters
In-house testing creates an obvious conflict of interest — the same company manufacturing the product is evaluating its quality. Independent third-party testing removes that conflict. The laboratory has no financial relationship with our sales and no incentive to pass a substandard batch.
When evaluating any peptide supplier, ask two questions: Who performed the testing? And will they show you the full COA before you buy? If either answer is evasive, that tells you something.
Questions About Our Testing
If you have questions about our testing protocols, need a COA for a specific batch, or want to verify the authenticity of a Certificate of Analysis, contact our team.