Quality standards
A COA is only useful if it describes the exact vial in your hands. This is how we make sure it does.
From sequence to sealed vial
Six stages, each with a pass or fail gate. A lot that fails any gate never reaches the catalog.
Browse the COA Library- 01
Synthesis
Fmoc solid-phase synthesis by qualified partners, with the sequence and modifications confirmed against our specification.
- 02
Purification
Preparative reverse-phase HPLC. Fractions are pooled only when they meet the purity target.
- 03
Lyophilization and fill
Freeze-dried and filled into Type I glass vials, sealed and crimped.
- 04
Third-party testing
A retained sample from the lot is sent to an independent laboratory for HPLC and MS.
- 05
Release
Lots with a passing COA are labeled with the matching lot number. Failing lots are rejected, never relabeled.
- 06
Fast dispatch
Orders confirmed before the daily cutoff usually ship the same business day, with tracking.
Release specification
The tests every peptide lot must pass before it is labeled for sale.
| Test | Method | Specification |
|---|---|---|
| Identity | Mass spectrometry (ESI-MS or MALDI-TOF) | Observed mass matches theoretical MW |
| Purity | Reverse-phase HPLC, UV 214 to 220 nm | ≥99% by peak area |
| Appearance | Visual inspection | White to off-white lyophilized powder (compound-specific exceptions noted) |
| Fill amount | Gravimetric | Meets label claim |
| Counter-ion | Reported on COA | Acetate or TFA, as stated |
What purity does and does not tell you
HPLC purity measures how much of the UV-absorbing material is the target sequence. It does not measure water or counter-ion content, which is why a 99% pure peptide can be 75 to 85% peptide by weight. Where net peptide content is measured, it is reported on the COA.
Mass spectrometry confirms identity. Together the two tests answer the questions that matter most: is this the right molecule, and how much of the sample is it?
Read our full guide: How to read a peptide certificate of analysis.
Relabel failing lots, reuse a COA across lots, or publish a COA without its chromatogram and spectrum.
Every vial label carries a lot number that maps to its synthesis record and COA.
Orders confirmed before the cutoff usually ship the same business day, tracked.
A sample of each lot is retained so results can be re-checked if a question arises.