Research peptide raw material
TB-500 Raw Material Supplier
TB-500 is the acetylated heptapeptide Ac-LKKTETQ, supplied as research-use raw powder from 5 g, cold-chain, or as lyophilized vials of 2 mg, 5 mg or 10 mg in kits of ten. Three public batch records sit in the Pepti COA library for it, each with an HPLC purity result and a molecular-weight result that you can read before you place an order.
Also known as Thymosin β4 fragment (17–23), Ac-LKKTETQ. Supplied by Bulk Peptide Works, manufactured by Pepti, Guangzhou.
Identity
TB-500 is a seven-residue fragment, not the whole protein
The name TB-500 belongs to a short synthetic peptide: an acetylated chain of seven amino acids, Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln, written in one-letter code as Ac-LKKTETQ. It is registered under CAS 885340-08-9 and listed on PubChem as CID 62707662 with the formula C38H68N10O14 and a molecular weight of 889.0 g/mol. The sequence corresponds to residues 17 to 23 of thymosin beta-4 with an acetyl group on the N-terminus, which is why catalogues also list it as thymosin β4 fragment (17–23).
Full-length thymosin β4 is a separate material. It is a 43-residue protein indexed under CAS 77591-33-4 with a mass of roughly 4,963 g/mol, far above the mass of the fragment. A supplier who quotes TB-500 against the thymosin β4 registry number, or the other way round, is quoting a different substance, and the molecular-weight result on the certificate will show which one was actually made. Put CAS 885340-08-9 on the purchase order and check that the certificate reports a mass close to 889 g/mol; that single comparison settles most naming disputes before they start.
The acetyl group matters for identity as well. Without it the same seven residues would have a lower mass, a different retention time on the chromatogram and a formula that does not match the one on this page. The public batch records for TB-500 report a molecular-weight result consistent with the acetylated form, so a buyer reading the record can confirm that the N-terminal modification is present. This page covers naming, documentation, the two supply formats, handling and the quotation. It says nothing about what the peptide does, because that is not what a raw material supplier is selling.
TB-500 identity and supply facts
| Compound | TB-500 (Acetylated heptapeptide) |
|---|---|
| Other names | Thymosin β4 fragment (17–23); Ac-LKKTETQ |
| CAS Registry Number | 885340-08-9 |
| PubChem CID | 62707662 |
| Molecular formula | C38H68N10O14 |
| Molecular weight | 889 g/mol (PubChem computed value for CID 62707662) |
| Sequence | Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln |
| Raw powder | Available from 5 g; dispatched cold-chain; quoted per gram |
| Lyophilized vials | 2 mg, 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 |
Batch records
What a TB-500 certificate shows, and what it leaves out
Each TB-500 lot is released with a certificate of analysis tied to its lot number. The certificate states the purity of the main peak by HPLC, the molecular-weight result from mass spectrometry, the manufacturing date, the test date and a retest date. Three lots are public in the Pepti library at present, at fills of 2 mg, 5 mg and 10 mg, and their purity results fall between 99.1% and 99.6%. Each figure belongs to the lot it was measured on. The library is a record of what has been made, not a promise about what the next lot will measure, and the certificate for your own lot is the one that counts.
Read the two numbers together. A molecular-weight result near 889.0 g/mol confirms that the peak is the acetylated heptapeptide rather than a deletion sequence or the full-length protein. The purity percentage reports how much of the chromatogram that peak occupies. What the certificate does not report is just as important for a quality file: the public summaries carry no fill-mass verification per vial, no water content, no counter-ion assay, no residual solvent figure, no endotoxin result and no sterility test. If any of those are needed, they are commissioned by the buyer at an outside laboratory, and the lot number is the thread that connects that outside result back to the material in the parcel.
Ask for the record before you pay if you want to. A quotation for allocated TB-500 stock names the lot it will be drawn from, and the entry for that lot is in the batch table on this page. Lots that have been made but not yet published are documented on the same template, and document availability is confirmed per lot on the quotation. The guide on matching a COA to the batch you receive walks through the comparison line by line.
Ordering
How a TB-500 order moves from enquiry to parcel
Each stage produces a document you can keep against the lot number.
-
Choose powder or vials, then the quantity
Raw powder is quoted per gram from 5 g and dispatched cold-chain. Vials are quoted by the kit of ten, in the 2 mg, 5 mg or 10 mg fill. The sample order is 1 kit (10 vials); a private-label OEM run begins at 50 kits (500 vials). Powder and a sample kit on the same enquiry is common when a buyer wants to compare the two formats from one production.
-
Give the destination and list the paperwork
The country of delivery decides the route and the cold-chain packing, so state it up front. Say if the batch record must be in your hands before payment, if you want the retest date confirmed in writing, or if your quality system needs the certificate in a particular layout.
Whether TB-500 may be imported into your jurisdiction is for you to establish. The quotation describes the goods; it does not give regulatory advice.
-
Read the quotation against the public record
The written quotation identifies the material by CAS 885340-08-9, states the format and quantity, gives the lead-time window that applies and, where stock is allocated, names the lot. Open that lot in the library and compare the purity and molecular-weight results with what you expected before you confirm.
-
Confirm and allow the typical window
A sample kit typically leaves in 3–7 days after the specification and payment are confirmed. A production batch is typically 10–14 days; an OEM repeat batch is typically 14–18 days. These are typical windows rather than fixed commitments, and the quotation states the one that applies.
-
Reconcile the parcel with the certificate
Check the lot number on each vial label or on the powder container against the certificate, weigh what your balance can resolve, and send a portion out for independent analysis if your process calls for it. Any discrepancy is raised with the lot number and photographs so it can be resolved against the record. The order photographs page shows how parcels are packed and labelled.
Powder or vials: the TB-500 version of the decision
The same production feeds both formats and both carry the same style of batch record. What changes is where the weighing happens and who is responsible for the fill.
| If you | Order | Because |
|---|---|---|
| Run your own filling line or need the material for method work | Raw powder, quoted per gram from 5 g | One weighed lot becomes as many of your own units as you choose, and you select the container and diluent |
| Send sealed units out to several end users | Lyophilized vials in kits of ten | Every vial is labelled with the fill and the lot, so each unit carries its own paper trail |
| Are checking a new source before committing volume | One sample kit, 1 kit (10 vials) | It is the smallest order that still arrives with a lot number and a record you can read in the library |
| Need vials under your own brand | A private-label run from 50 kits (500 vials) | OEM runs are scheduled as a production batch and quoted with the OEM repeat-batch window on reorders |
Quote both formats on one enquiry if the decision is still open; the guide on vials versus raw powder sets out the trade-offs.
Two formats for TB-500
-
Raw powder
TB-500 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.
-
Lyophilized vials
TB-500 in finished vials
Fills of 2 mg, 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 TB-500
3 public lot records for TB-500, with chromatographic purity results from 99.1–99.6%. 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 |
|---|---|---|---|---|
| PEP260706-BT2 | 2 mg | 99.1% | 889.21 Da | 2026-07-12 |
| PEP260715-BT5 | 5 mg | 99.6% | 889.21 Da | 2026-07-29 |
| PEP260715-BT10 | 10 mg | 99.3% | 889.21 Da | 2026-07-29 |
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
Keeping TB-500 within its retest date
TB-500 leaves Guangzhou as a dry solid. Raw powder is weighed into a sealed container and packed cold-chain; vials hold a freeze-dried cake under a stopper and a crimped cap. The retest date on the certificate is the point at which material still in your stores should be examined again before it is relied on; it is not an expiry after which the peptide becomes something else. The simplest discipline is to record the lot number, the arrival date and the retest date in your inventory system when the parcel is opened, so that the retest falls due on a calendar and not by surprise.
Between uses the container stays sealed, cold and shielded from light. The error that most often appears later as an extra peak on a chromatogram is a container that has been warmed, opened, closed and chilled again several times, each cycle admitting a little moisture. Nothing here is a direction for use; it is the handling that any lyophilized peptide held as a reference standard receives, and the storage and retest guide goes through it step by step.
Who this page is for
Three readers this TB-500 page was written for
-
01
A laboratory that needs a second source
You hold TB-500 from another supplier and want a documented alternative. Order one kit, put its certificate beside the one you have, and compare the molecular-weight result and the purity before you decide whether to move volume or switch to powder.
-
02
A distributor building a non-GLP-1 list
You want TB-500 from the same manufacturer as BPC-157, Ipamorelin and the rest of your list so that certificates share a layout and lot numbers follow one pattern. Put every line on a single enquiry; the longest lead-time window sets the dispatch date.
-
03
A brand owner planning labelled vials
You want TB-500 in vials under your own label. The run is planned from 50 kits (500 vials), documented lot by lot like any other production batch, and reorders carry the OEM repeat-batch window. Artwork and carton specifications are dealt with once the quotation has been agreed.
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.
TB-500 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.
Full-length thymosin β4 (CAS 77591-33-4, 43 residues, about 4,963 g/mol) is a different substance. This page is the acetylated 17–23 fragment that the trade calls TB-500.
TB-500 supply questions
Is TB-500 the same thing as thymosin β4?
No. TB-500 is the acetylated 17–23 fragment, seven residues with a molecular weight of 889.0 g/mol under CAS 885340-08-9. Thymosin β4 is the complete 43-residue protein under CAS 77591-33-4. A certificate that reports a mass in the region of 4,963 g/mol describes the protein, not the fragment this page is about.
How many TB-500 batch records can I read before ordering?
Three at present, covering the 2 mg, 5 mg and 10 mg fills, each with its HPLC purity, its molecular-weight result and its test and retest dates. They are listed in the batch table on this page. For an allocated order the quotation names the lot, so the relevant record can be read first.
Can I order TB-500 as powder rather than vials?
Yes. Raw powder is quoted per gram from 5 g and shipped cold-chain, with the same kind of lot certificate as the vials. Buyers who fill their own containers or who need the material for analytical work usually take powder; buyers who distribute sealed units take vials.
What do the lead times for TB-500 look like?
A sample kit typically dispatches in 3–7 days after specification and payment are confirmed, a production batch typically in 10–14 days and an OEM repeat batch typically in 14–18 days. Each is a typical window, and the written quotation states the one that applies to your order.
Quote TB-500 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.