At a glance · 11 Nov 2026
- Suppliers tracked
- 101 list PE-22-28; 93 with a listing on sale (103 listings confirmed in stock)
- Sizes on sale
- Suppliers on this page sell PE-22-28 in 5 mg, 8 mg and 10 mg vials. Some also sell packs of 3 to 10 vials, compared per mg of the whole pack rather than against single vials. Other forms on sale (spray and kit) are different products and are not compared per mg with vials. How prices are compared
- Price per mg, single vials (USD)
- US$2.60/mg to US$67.50/mg, median US$6.25/mg, across 28 single-vial listings from 25 suppliers
- Price per mg, multi-vial packs (USD)
- US$1.10/mg to US$5.00/mg, median US$3.60/mg, across 7 pack listings from 6 suppliers
- Test certificates
- 1 of 101 suppliers have one for PE-22-28 on file with us
What PE-22-28 is
PE-22-28 is a synthetic seven-amino-acid peptide designed in 2017 by a French research group as a shortened, longer-lasting version of spadin, a natural peptide fragment that blocks the TREK-1 potassium channel. In mice it produced antidepressant-like behaviour within four days and increased new neuron growth in the hippocampus. It has never been tested in a human, and every claim made for it rests on rodent and cell studies from a single laboratory. Read the full PE-22-28 guide, with the published research and references.
Before you choose a PE-22-28 supplier
Price per mg is only half the comparison. Check that the supplier publishes a certificate of analysis for the batch it is selling, ideally from an independent laboratory, and that the certificate confirms identity as well as purity: our guide on how to read a COA shows what to look for. A price far below the rest of the list is more often a warning than a bargain; peptide prices explained sets out why.
For what PE-22-28 is and what published studies have found, see our PE-22-28 guide. Handling questions are covered in how to store peptides, and the peptide calculator converts a vial size and water volume into concentration and syringe units. Rules on buying and importing differ by country: see legal status by country, or narrow this list to your region above.
Checking a PE-22-28 certificate of analysis
- The certificate names a laboratory you can find independently, and ideally one with no stake in the result.
- It carries a batch or lot number that matches the product page or the vial label, and a test date.
- It confirms identity by mass spectrometry, not only purity by HPLC. Purity alone does not show the vial contains PE-22-28.
- It includes the chromatogram and mass spectrum, not just a summary table.
- Where the laboratory offers online verification of its reports, the report number checks out.
Red flags
- No certificates at all, or certificates available only “on request”.
- The same certificate used for several products or several years of stock.
- Payment only by cryptocurrency or bank transfer, with a discount for paying that way.
- A price far below every other supplier on this page.
- No way to contact the store other than a web form.
- Vials labelled only with a code rather than the product name and strength.
How to spot a fake peptide supplier explains each of these in more detail, and third-party peptide testing covers what independent results can and cannot prove.
Vials, capsules and pre-mixed products
Most research peptides are sold as freeze-dried (lyophilised) powder in sealed vials, which is mixed with a diluent such as bacteriostatic water before use in the lab. Some suppliers also sell pre-mixed solutions, nasal sprays or capsules under the same name. These are different products with different stability and dosing, so compare price per mg only between the same form, and check which form a listing is before comparing it with the rest of the table.
How this list is built: suppliers appear because they list PE-22-28 on their own website, read by our catalogue checks; nobody pays to be included or to move up. Ranking is by PepFinder Score, with stores that have nothing on sale after those that do. Prices, sizes and stock are as each site listed them when checked and may have changed.
