DOCUMENTATION GUIDE / 5 MIN
Purity and net content: two different COA results
Learn the difference between purity percentage, nominal presentation and reported net content, using the available COAs as examples.
By Honduras Péptidos · Published October 29, 2026
A percentage is not a quantity in milligrams
When looking at a COA, it is easy to focus on the highest percentage. But purity percentage, nominal label quantity and reported net content answer different questions. When reading the document, keep each field’s exact name and unit.
- Nominal presentation: the quantity used to identify the catalog or label presentation, such as 10 mg. It is not the result of a new test.
- Purity: the percentage result the laboratory reports under a specific method. In the MOTS-C and RETATRUTIDE COAs available here, the field is Purity (HPLC-UV). It should not automatically be interpreted as the percentage of all vial mass.
- Net content: the value the report presents in milligrams under Net Content. Read its scope and method in the document; do not substitute the nominal label quantity.
Examples from the available certificates
These values were transcribed from the linked PDFs. They illustrate document fields, not a dose calculation or a guarantee of every vial’s result.
| Presentation / batch | Nominal | Reported purity | Reported content |
|---|---|---|---|
| MOTS-C ↗ MVR-MOTS-002 | 10 mg | 99.68% | 11.51 mg |
| RETATRUTIDE ↗ MVR-RT10-001 | 10 mg | 99.83% | 12.18 mg |
| KLOW ↗ MVR-KL80-003 | 80 mg | 99.387% * | 83.27 mg |
* KLOW: Blend Avg Purity and Blend Avg Net Content are blend averages in the Kovera Labs report. The PDF includes a component breakdown.
For example, the MOTS-C COA retains a nominal identification of 10 mg while reporting 11.51 mg net content. Reading both avoids confusing the commercial presentation with that sample’s analytical result.
What to avoid when comparing results
- Do not automatically multiply net content by purity percentage to advertise a corrected quantity. First establish what each method measures and how the laboratory defines it.
- Do not treat a blend average as the purity of each component.
- Do not transfer results from one batch to another, even when the name and nominal presentation match.
- Do not confuse an endotoxin result with a sterility test. They are different fields and questions.
Sources and scope
The examples come from the linked original COAs, not a test performed by Honduras Péptidos. As a general reading reference, the WHO certificate model brings together sample and batch identification, tests, results, criteria and dates. The reference does not imply WHO endorsement of these vials or laboratories.