Seven steps, no discretion.
Our specifications are fixed before anything is measured. A result is not interpreted, it is compared.
- 01
Goods receipt
Every batch receives a unique lot number on arrival. Manufacturer documents are archived but not accepted as evidence.
- 02
Sampling
Samples are drawn from every batch and handed to an accredited testing laboratory independent of us.
- 03
Identity (ESI-MS)
The measured mass must match the mass calculated from the sequence. Tolerance ± 0.5 Da, several charge states.
- 04
Purity (RP-HPLC)
C18, 0.1 % TFA, 20 min gradient, detection at 220 nm. Purity as area percent, largest single impurity reported separately.
- 05
Content and residues
Water content by Karl Fischer, acetate content by ion chromatography, peptide content by nitrogen determination.
- 06
Release
A batch is released only if all values lie within the pre-defined specification. Otherwise it is blocked and not shipped.
- 07
Publication
The report is published at puralabs-research.com/en/coa/LOT. The QR code on the label leads there.
What a batch
has to meet.
Limits for all peptide lyophilisates. Bacteriostatic water has its own criteria (benzyl alcohol 0.9 %, sterility, endotoxins).
| Appearance | White to off-white lyophilisate |
| Identity (ESI-MS) | Matches theoretical mass, ± 0.5 Da |
| Purity (RP-HPLC, 220 nm) | ≥ 98.0 % |
| Largest single impurity | ≤ 1.0 % |
| Peptide content | ≥ 80.0 % |
| Water content (Karl Fischer) | ≤ 8.0 % |
| Acetate content | ≤ 15.0 % |
| Solubility in water | Clear and colourless |