6 independent third-party assays of Selank 10mg, covering 6 vendors.
Measured purity across those assays runs from 98.0% to 99.8%, median 99.7%. The spread is the point: it is variation between lots and between vendors, not a single number that describes the compound.
Assay dates span 2023-11-28 to 2026-03-31.
Manufacturer recorded on the certificates: aura, Qingdao Sigma Chemical Co., Ltd.
A certificate of analysis describes the lot that was submitted and nothing else. It is not a guarantee about a later batch, and purity is not identity — a sample can assay clean and still be the wrong compound, or the right compound at the wrong concentration. Vendors with no assay row below have not been tested here, which is not the same as having failed.
1 further assay submitter could not be matched to a vendor profile — the certificate names a mailbox or handle rather than a company — so it is counted in the totals above but not listed below.
| Vendor | Assays | Median measured purity | Most recent |
|---|---|---|---|
| Henan Sahe Peptide | 1 | 99.8% | 2026-03-17 |
| Certified Peptides | 1 | 99.8% | 2026-03-31 |
| aurapp.5188 | 1 | 99.7% | 2025-12-22 |
| ZLZ Peptide | 1 | 99.4% | 2025-11-20 |
| Qingdao Sigma Chemical QSC | 1 | 98.0% | 2023-11-28 |
Vendors assayed: Henan Sahe Peptide, Certified Peptides, aurapp.5188, ZLZ Peptide, Qingdao Sigma Chemical QSC.