Research peptide raw material
Selank Raw Material Supplier
Selank is the seven-residue peptide Thr-Lys-Pro-Arg-Pro-Gly-Pro, 751.9 g/mol, available as research-use raw powder from 5 g with cold-chain dispatch or as lyophilized vials of 5 mg and 10 mg in kits of ten. The Pepti COA library holds two public batch records for it, each stating an HPLC purity result, a molecular-weight result and the test and retest dates.
Also known as Thr-Lys-Pro-Arg-Pro-Gly-Pro, Tuftsin-PGP. Supplied by Bulk Peptide Works, manufactured by Pepti, Guangzhou.
Identity
Selank: a tuftsin sequence with a Pro-Gly-Pro tail
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its registry number is CAS 129954-34-3, its PubChem entry is CID 11765600, its formula is C33H57N11O9 and its molecular weight is 751.9 g/mol. The first four residues, Thr-Lys-Pro-Arg, are the tetrapeptide tuftsin; the last three are Pro-Gly-Pro. Catalogues therefore also list the material as Tuftsin-PGP, and the two names describe one and the same chain.
The peptide is easy to confuse on paper with Semax, which ends in the same three residues but begins with a different four and has its own registry number and a higher mass. The two are separate lines on a quotation and separate records in the COA library. A purchase order that carries the Selank CAS number and the full sequence leaves no doubt about which of the two is being bought, and the molecular-weight result on the certificate will confirm it on receipt.
Variants also exist in the trade: an N-acetylated form, a C-terminal amide, or both together. Each of those changes the formula and the mass, and none of them is what CAS 129954-34-3 describes. The registry number stands for the unmodified peptide with a free N-terminus and a free C-terminal acid. If the certificate you are offered reports a mass that does not sit close to 751.9 g/mol, you are looking at one of the variants or at a different compound. This page deals with how Selank is named, documented, supplied, handled and quoted. It does not say what the peptide does.
Selank identity and supply facts
| Compound | Selank (Heptapeptide) |
|---|---|
| Other names | Thr-Lys-Pro-Arg-Pro-Gly-Pro; Tuftsin-PGP |
| CAS Registry Number | 129954-34-3 |
| PubChem CID | 11765600 |
| Molecular formula | C33H57N11O9 |
| Molecular weight | 751.9 g/mol (PubChem computed value for CID 11765600) |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Raw powder | Available from 5 g; dispatched cold-chain; quoted per gram |
| Lyophilized vials | 5 mg, 10 mg per vial; 10 vials per kit; sample 1 kit (10 vials); private-label OEM from 50 kits (500 vials) |
| Grade | Research use only. Not for human or veterinary use. |
| Manufacturer | Pepti, Guangzhou |
Documentation
The Selank batch record, line by line
Every Selank lot leaves with a certificate of analysis for that lot number. It reports the HPLC purity of the main peak, the molecular-weight result from mass spectrometry, the date of manufacture, the date of testing and the retest date. Two lots are public in the Pepti library at the moment, filled at 5 mg and 10 mg, with purity results of 98.9% and 98.8%. These are the results for those lots and nothing more; they describe what the production has reported to date rather than what any future lot must achieve. Your quality file should carry the figure from the certificate for the lot you actually receive.
The two numbers answer two different questions. The molecular-weight result, read next to the CAS number, answers whether the main peak is the Selank heptapeptide at about 751.9 g/mol or something else. The purity result answers how much of the chromatogram is that peak. What neither answers, and what the public summary does not pretend to answer, is the counter-ion, the water content, the exact fill of a given vial, residual solvents, endotoxin or sterility. Those are tests a buyer arranges independently, and the lot number is what ties an outside laboratory report to the vials or powder on the bench.
You do not have to pay to see the record. Where stock is allocated, the quotation names the lot and its entry is in the batch table on this page. A lot that exists but has not been published yet is written up on the same template, and its certificate goes out with the order. The quality page describes the documentation system as a whole, and the FAQ answers the general questions about it.
Ordering
The Selank order path
Five steps from enquiry to parcel, each with a document that references the lot.
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Decide on format and quantity
Raw Selank powder is quoted per gram from 5 g with cold-chain dispatch. Vials are quoted per kit of ten in the 5 mg or 10 mg fill. The sample order is 1 kit (10 vials). A private-label OEM run is planned from 50 kits (500 vials). A combined enquiry for powder plus a kit is handled as one quotation.
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State the destination and the documents you require
The delivery country determines the shipping route and the packing. Tell us whether you need the batch record before you pay, whether you want the retest date written into the quotation, and whether the certificate must follow a layout your quality system expects.
Confirming that Selank may be imported into your country is your responsibility. The quotation sets out the goods and the documents and does not offer regulatory opinion.
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Check the quotation and the public record together
The quotation names Selank by CAS 129954-34-3, gives the format, the quantity and the lead-time window, and for allocated stock names the lot. Open the lot in the library and compare purity and molecular-weight results with your expectation before you confirm.
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Confirm and allow the stated window
A sample kit is typically on its way 3–7 days after specification and payment are confirmed. A production batch typically takes 10–14 days; an OEM repeat batch typically takes 14–18 days. All three are typical windows; the one that applies is written on the quotation.
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Verify the parcel against the certificate
Match the lot number on each vial or the powder container to the certificate. Weigh what your equipment allows and send a portion for independent analysis if that is part of your procedure. Report any discrepancy with the lot number and photographs so that it can be resolved against the written record.
Selank: when powder fits and when vials fit
One production, two formats, the same batch record. The question is where the weighing is done.
| Need | Format | What it gives you |
|---|---|---|
| Filling your own containers or building an analytical method | Raw powder from 5 g | Control over container, diluent and unit size from one weighed lot |
| Distributing sealed units to several sites | Vials in kits of ten | A labelled, lot-numbered unit that can be tracked individually |
| Testing a new supplier before volume | One sample kit | A lot number and a readable public record on the smallest possible order |
| Vials carrying your own brand | OEM run from 50 kits (500 vials) | Scheduled as a production batch, with the OEM repeat-batch window on reorders |
Quote both formats together if the decision is open. The comparing quotes guide explains how to put a per-gram and a per-kit quotation side by side.
Two formats for Selank
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Raw powder
Selank as raw material
From 5 g per order, quoted per gram, dispatched cold-chain. The batch COA confirmed for the lot states HPLC purity and MS identity. Choose this when your own fill-and-finish or analytical work needs bulk material.
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Lyophilized vials
Selank in finished vials
Fills of 5 mg, 10 mg per vial, ten vials per kit. A sample order is 1 kit (10 vials); private-label OEM starts at 50 kits (500 vials). Choose this when you need a finished, sealed unit per sample rather than weighed powder.
Public lot records for Selank
2 public lot records for Selank, with chromatographic purity results from 98.8–98.9%. Each row is one lot at one fill: the lot number, the fill, the HPLC purity result, the mass-spectrometry molecular-weight result and the test date.
| Lot | Fill | HPLC purity | MS molecular weight | Tested |
|---|---|---|---|---|
| PEP260724-SK5 | 5 mg | 98.9% | 751.32 Da | 2026-07-30 |
| PEP260724-SK10 | 10 mg | 98.8% | 751.32 Da | 2026-07-30 |
Lot records are mirrored from the manufacturer's public COA library — verify any lot there.
Snapshot taken 2026-10-20; library last reviewed 2026-08-24. Withdrawn records are excluded.
Lead times
Three stages, each quoted as a typical window after specification and payment confirmation; not a fixed commitment. The quotation states the window that applies to your order.
- 01Sample kittypically 3–7 days
- 02Production batchtypically 10–14 days
- 03OEM repeat batchtypically 14–18 days
Handling
Selank in storage and in transit
Selank is shipped dry: weighed powder in a sealed container under cold-chain packing, or a freeze-dried cake in a stoppered and crimped vial. The retest date printed on the certificate is a reminder to re-examine material still held, not a date on which it stops being Selank. Record the lot number, the receipt date and the retest date when the parcel is opened, and let the retest come up on a schedule.
Keep the container closed, cold and out of light, and open it only when there is a reason to. A container that goes through repeated warm-open-close-chill cycles picks up moisture and that is what tends to show, months later, as a new shoulder on the main peak. This is reference-material housekeeping, not a direction for use. The storage and retest guide expands on it.
Who this page is for
Three Selank procurement situations
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01
A laboratory replacing or duplicating a reference lot
You hold Selank already and want a second, documented source. A single kit lets you set the two certificates side by side and compare the molecular-weight result and the purity before you commit to powder or a larger kit order.
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02
A distributor stocking the Pro-Gly-Pro pair
Selank and Semax are usually listed together and mixed up together. Buying both from one manufacturer means matching certificates and one lot-numbering scheme, and the quotation can carry both lines, with the longer lead-time window governing dispatch.
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03
A brand owner ordering a labelled run
You want Selank vials under your own label. The run starts at 50 kits (500 vials), is documented lot by lot, and reorders use the OEM repeat-batch window. Label artwork and carton specification are agreed after the quotation.
What this page does not claim
Pepti does not present itself as a cGMP drug-substance (API) manufacturer or CDMO and does not publish a GMP certificate or DMF.
Selank is supplied for research use only and not for human or veterinary use. Nothing on this page describes an effect, a protocol or a use; a buyer who needs that information is on the wrong site.
Selank supply questions
Which CAS number goes on a Selank purchase order?
CAS 129954-34-3, with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro written out beside it. That registry number appears on the public records in the Pepti library and on the PubChem entry for CID 11765600. Tuftsin-PGP can go on a second line as a trade name, but the CAS number is what the certificate quotes.
How is Selank different from Semax on a quotation?
They are two separate lines with two different CAS numbers, two different sequences and two different masses, 751.9 g/mol against 813.9 g/mol. They share only the last three residues. Each has its own lot numbers and its own COA records, and a certificate for one cannot stand in for the other.
What purity do the public Selank records report?
The two public lots report 98.9% for the 5 mg fill and 98.8% for the 10 mg fill. Those are HPLC results for those specific lots. They indicate the range this production has reported, not a specification; the figure on the certificate for your lot is the one to record.
What is the minimum Selank order and the typical lead time?
Either 1 kit (10 vials) of one fill or 5 g of raw powder. After specification and payment are confirmed a sample kit typically dispatches in 3–7 days. Private-label OEM vials start at 50 kits (500 vials) and are planned as a production batch, typically 10–14 days for a first run.
Quote Selank raw material or vials
Tell us the format (raw powder from 5 g, or vials and which fill), the quantity, the destination country and whether you need the batch COA before payment. Replies come with the applicable lot record.
Prefer email? You can email the sales desk; put the compound and quantity in the subject line.