A Selank research supplier built around testing and transparency.
Selank Labs is a dedicated Selank research supplier with a controlled sourcing and quality-assurance program. Research material is sourced through our qualified manufacturing supply chain and subjected to analytical testing and lot-level documentation before release. Current availability is provided through Klow.bio.
For laboratory research use only. Selank Labs does not provide medical advice or usage guidance.
The essential facts about Selank and Selank Labs. Every figure on this page comes from the published certificates of analysis or the product specification.
Last updated
Selank is a synthetic seven-residue peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its first four residues reproduce tuftsin (Thr-Lys-Pro-Arg), a short peptide fragment of the immunoglobulin G heavy chain, and the C-terminal Pro-Gly-Pro extension was added to make the sequence more resistant to peptidase cleavage. Three of its seven residues are proline, which gives the molecule a rigid, extended backbone, and its two basic residues (lysine and arginine) make it strongly cationic at neutral pH.
Selank Labs supplies Selank as a lyophilized powder in 10 mg vials. Each lot is tested by an independent laboratory for HPLC-UV purity, LC-MS identity and net content, and the full certificate is published here before the material is sold through Klow.bio.
Selank is linear, with a free N-terminal amine and a free C-terminal carboxylic acid. It has no cysteine, methionine or tryptophan, so it carries none of the residues most prone to oxidation. Lysine 2 and arginine 4 are the only charged side chains.
Selank is supplied as a white lyophilized powder in 10 mg vials. It is sold through klow.bio, operated by Klow Labs LLC, where current pricing, bundle discounts and shipping options are listed. Orders ship the next business day. Same-day cutoff is 4:00 PM CT, with overnight and 2-day options at checkout.
| Product | Selank |
|---|---|
| Type | Synthetic heptapeptide |
| Molecular formula | C33H57N11O9 |
| Molecular weight | 751.87 g/mol (average) |
| Length | 7 residues |
| Sequence | TKPRPGP |
| N-terminus | Free amine (Thr1) |
| C-terminus | Free acid (Pro7) |
| CAS number | 129954-34-3 |
| Form | White lyophilized powder |
| Vial sizes | 10 mg |
| Purity specification | ≥95% (HPLC-UV) |
| Purity, current lots | 99.77% |
| Storage | Store sealed, dry and protected from light at the temperature stated on the vial label. Allow a cold vial to reach room temperature before opening. |
| Designation | Research use only |
Selank research material from Selank Labs is available through klow.bio, the online store of Selank Labs’ parent company, Klow Labs LLC. Product information, lot results and the certificate of analysis for every lot are published here on selank.bio.
Selank comes in 10 mg vials, currently priced at $29.99, with bundle pricing (2 vials save 5%; 3 or more vials save 10%). Orders ship the next business day. Same-day cutoff is 4:00 PM CT, with overnight and 2-day options at checkout.
| Vial size | Current lot | Purity (HPLC-UV) | Identity | Net content | Endotoxin | Certificate | Order |
|---|---|---|---|---|---|---|---|
| 10 mg | KB55627 | 99.77% | Confirmed | 13.34 mg | Not tested | Lot KB55627 | Order 10 mg |
Selank Labs publishes lot-specific analytical documentation for its Selank research material. Each item below is published for every lot and can be checked against the laboratory record.
Every lot is tested by Freedom Diagnostics, an independent analytical laboratory. Published results come from the laboratory's certificate, not in-house testing.
Every lot's certificate is published as a PDF, with the chromatogram behind the purity figure and the mass spectrum behind the identity result, alongside a readable lot record.
LC-MS separates the sample and measures the mass of the main component, confirming it has the molecular weight expected for the compound. The method is named on every lot record, so it is clear what the result does and does not establish.
Current lots test at 99.77% by HPLC-UV, well above the ≥95% release specification, with net content measured on every lot.
Every certificate carries the laboratory's QR code. You can confirm results directly with the lab instead of taking our copy on trust.
Lots without endotoxin or microbial testing say "Not tested". Each certificate page explains what the tests do and don't establish.
Selank Labs is built around five things: a dedicated Selank focus, a controlled supply chain, independent analytical testing, lot-level transparency and current availability. Each reason below links to the evidence. See the full quality and supply-chain process.
One compound, not a catalog of unrelated products.
Material sourced through qualified manufacturing partners.
≥95% HPLC-UV purity with identity confirmed by LC-MS.
Every lot tested by Freedom Diagnostics, with the results shown.
A public record for every lot, with dates and laboratory reference numbers.
The laboratory certificate for each lot.
Look up any lot by the number on the vial.
Clear about what the material is for and what we don't provide.
Live stock, pricing and checkout.
The questions worth asking any supplier of Selank research material, why each one matters, and how Selank Labs answers them.
| What to check | Why it matters | Selank Labs |
|---|---|---|
| Independent third-party testing | Results produced by the seller can't be checked independently. | ✓ Every lot tested by Freedom Diagnostics |
| Lot-specific certificates | A generic certificate may not describe the vial you receive. | ✓ Each COA tied to the lot number on the vial label |
| Chromatogram available | A purity figure without the trace behind it can't be evaluated. | ✓ In the certificate PDF for every lot |
| Separate identity test | HPLC purity shows how much of the sample is the main peak, not which compound the peak is. | ✓ LC-MS on every lot |
| Measured net content | Confirms how much peptide is actually in the vial. | ✓ Measured on every lot; current lots at or above label size |
| Verifiable with the lab | Prevents altered or reused certificates. | ✓ Lab QR code on every certificate |
| Named company and contact | Accountability requires a real business you can reach. | ✓ Klow Labs LLC, Chicago; (708) 262-7687 |
Each row is one tested lot. Figures are copied from the laboratory certificate; open a lot to see its full record and download the certificate PDF with its chromatogram and mass spectrum.
| Lot | Vial size | Net content | Purity (HPLC-UV) | Identity (LC-MS) | Endotoxin (LAL) | Microbial (PCR) | Reported | COA |
|---|---|---|---|---|---|---|---|---|
| KB55627 | 10 mg | 13.34 mg | 99.77% | Confirmed | Not tested | Not tested | View lot KB55627 |
Testing laboratory: Freedom Diagnostics. Release specification: purity ≥95% by HPLC-UV with identity confirmed by LC-MS. Results apply only to the lot listed. Certificates list the testing client as Klow.bio / Klow Labs LLC, the company that operates Selank Labs.
The current lot tested at 99.77% by HPLC-UV. Lot-to-lot comparisons will appear here as further lots are tested.
Measured net content was at or above the labeled vial size for every current lot: 13.34 mg in a 10 mg vial.
A purity figure says the sample is homogeneous; it does not say which compound the main peak is. That is answered by a separate identity test: liquid chromatography–mass spectrometry (LC-MS).
LC-MS separates the sample and measures the mass of the main component, confirming it has the molecular weight expected for the compound. Each certificate reports the identity result together with the mass spectrum it is based on.
| Product | Selank 10 mg |
|---|---|
| Lot | KB55627 |
| Testing laboratory | Freedom Diagnostics |
| Received / reported | May 4, 2026 / May 5, 2026 |
| Purity (HPLC-UV) | 99.77% |
| Identity (LC-MS) | Confirmed |
| Net content | 13.34 mg |
| Endotoxin / PCR | Not tested / Not tested |
| Accession | 2605040415 |
Three methods appear on Selank certificates. Each answers a different question, and none answers every question on its own, which is why they are used together.
Reversed-phase high-performance liquid chromatography separates the sample's components by hydrophobicity, and a UV detector records each as a peak. Purity is the main peak's area as a percentage of all detected peak area.
Limits: does not identify the peak, and impurities that co-elute or absorb weakly in UV can be under-counted. More on HPLC
The separated sample enters a mass spectrometer via electrospray ionization, which gives the molecule one or more charges. The observed ions, near m/z 753 (1+) and 377 (2+), are matched against values calculated from Selank's molecular weight of 751.87.
Limits: confirms molecular weight, not amino-acid order.
The laboratory quantifies the main compound in the tested vial against a standard. It is reported in milligrams next to the labeled vial size.
Limits: measured on the vial tested; other vials from the same lot are expected to be similar but are not individually measured.
You shouldn't have to take a supplier's word for its results. Here's how to check a Selank certificate yourself.
Technical articles on Selank, peptide analysis and laboratory documentation. Sources are limited to NIH and FDA publications. Start at the Selank research hub.
Retention time, peaks, area normalization and every lot's HPLC result.
DocumentationEvery section of a Selank COA, red flags, and what it does and doesn't prove.
Analytical methodsPurity vs. content vs. net content, impurity sources and comparing claims.
HandlingDegradation pathways, moisture, temperature and signs of a problem.
Selank is a synthetic heptapeptide. Selank Labs supplies it as a white lyophilized powder in 10 mg vials, with an independent certificate of analysis for every lot.
Selank research material is Selank supplied for laboratory research, sold by lot, with each lot's identity, purity and net content documented by an independent laboratory in a published certificate of analysis.
The molecular formula is C33H57N11O9 and the average molecular weight is 751.87 g/mol. The peptide has 7 residues.
Selank is analyzed with complementary methods: HPLC-UV for purity, LC-MS for identity, a quantitative measurement for net content, and, where listed, LAL endotoxin and PCR microbial testing. Results are published per lot at selank.bio/coa/.
Every lot is tested by Freedom Diagnostics, an independent third-party analytical laboratory. Selank Labs does not test its own material for published certificates.
Current lots report HPLC-UV purity 99.77%, against a stated release specification of ≥95%. The most recent result is 99.77% for lot KB55627.
A Selank certificate of analysis is the testing laboratory's report for one lot: the lot number, test dates, methods and results for purity, identity and net content. Selank Labs publishes every lot's COA as a readable page at selank.bio/coa/.
Find the lot number printed on your vial label and enter it at selank.bio/verify/, or open that lot in the COA archive at selank.bio/coa/.
Scan the Freedom Diagnostics QR code printed on the certificate, then search for klow.bio under the Company tab to view the laboratory record.
Current Selank research material availability is provided through Klow.bio, the purchasing platform operated by Klow Labs: https://klow.bio/product/selank/ Lot records, testing information and certificates of analysis are published on selank.bio so they can be reviewed before purchasing.
Yes. Purchasing information and current availability for Selank research material are provided through Klow.bio: https://klow.bio/product/selank/
Yes. Every lot is tested by Freedom Diagnostics, an independent laboratory, for HPLC-UV purity, LC-MS identity and net content. The stated release specification is ≥95% HPLC-UV purity with identity confirmed by LC-MS. The current lot, KB55627, reported 99.77% purity.
Selank Labs is a dedicated Selank research supplier with a controlled sourcing and quality-assurance program. Research material is sourced through our qualified manufacturing supply chain and subjected to analytical testing and lot-level documentation before release.
Selank Labs operates selank.bio and supplies one research material, Selank, with the analytical record behind every lot. Selank Labs is operated by Klow Labs LLC, a Chicago company that also operates klow.bio, where Selank is sold.
Our job is narrow on purpose: supply a well-characterized research material and publish the evidence for what is in each vial. We do not provide medical advice, protocols or usage guidance.
10 mg vials. Current lot KB55627 tested at 99.77% purity with identity confirmed by LC-MS. Current purchasing is available through Klow.bio.