Peptide Purity Testing &
Certificate of Analysis
Gold Standard Analytics provides ISO 9001 certified third-party peptide purity testing using HPLC and mass spectrometry. Every COA includes a unique accession number your customers can verify online.
Peptides We Test
We test all classes of research peptides and active pharmaceutical ingredients. Below are the most commonly requested compounds — but our testing capabilities extend to any synthesized peptide or API.
Testing Semaglutide or Tirzepatide? See our dedicated GLP-1 testing page →
Available Test Panels
- HPLC purity %
- Single compound
- Digital COA
- Public verification
- HPLC purity %
- MS/MS identity confirmation
- Net peptide content
- TFA quantification
- Digital COA
- Public verification
- Everything in Purity + Identity
- Endotoxin (LAL assay)
- Sterility testing
- Heavy metals screen
- Priority processing
Our Testing Methods
HPLC — High-Performance Liquid Chromatography
The primary method for peptide purity quantification. HPLC separates the components of your sample via a mobile phase and stationary phase, then measures the relative abundance of each peak. The result is a precise purity percentage — for example, 98.4% — along with identification of any impurities present above the detection threshold.
Mass Spectrometry (MS/MS)
Used for definitive identity confirmation. Mass spectrometry measures the molecular weight of the intact peptide and fragments it via tandem MS/MS to confirm the amino acid sequence. This eliminates any ambiguity about what compound is present. Combined with HPLC, it provides dual-method confirmation.
Net Peptide Content (NPC)
Measures the true active peptide mass as a fraction of total sample weight. Peptide powders typically contain TFA counter-ions, moisture, and excipients that increase mass without adding active compound. NPC testing reveals the actual dose your customers receive per milligram.
TFA Quantification
Trifluoroacetic acid (TFA) is a counter-ion commonly present in HPLC-purified peptides. At high concentrations it can be harmful. We quantify TFA content using ion chromatography and report levels relative to regulatory thresholds.
Ready to test your peptides?
Submit your sample and receive a publicly verifiable COA in 5–7 business days. Your card isn't charged until we receive your sample.
Start Your Submission