BPC-157 and TB-500 compared
BPC-157 vs TB-500: origin, sequence, molecular weight, CAS numbers, solubility and storage of two commonly researched peptides. For laboratory research use only.
BPC-157 and TB-500 are two of the most frequently studied synthetic peptides in preclinical research, and they are often discussed together. Chemically they are unrelated: they come from different parent proteins, differ in size and sequence, and behave differently in solution. This guide sets out the differences that matter at the bench.
At a glance
| BPC-157 | TB-500 | |
|---|---|---|
| Origin | Partial sequence of a protein found in gastric juice (“body protection compound”) | Synthetic fragment based on thymosin β4, a 43-amino-acid actin-binding protein |
| Length | 15 amino acids | 7 amino acids (Ac-LKKTETQ, the 17–23 region of thymosin β4) |
| Sequence | GEPPPGKPADDAGLV | Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln |
| Molecular formula | C62H98N16O22 | C38H68N10O14 |
| Molecular weight | ≈1419.5 g/mol | ≈889.0 g/mol |
| CAS number | 137525-51-0 | 885340-08-9 |
| Form supplied | Lyophilised powder | Lyophilised powder |
BPC-157
BPC-157 is a pentadecapeptide whose sequence was identified within a larger protein isolated from gastric juice. Its proline-rich stretch (PPP) makes it unusually resistant to enzymatic breakdown compared with many linear peptides of similar length, and it is noted for stability in aqueous solution. It contains no cysteine, methionine or tryptophan, so oxidation is a minor concern; the two aspartic acid residues are the more likely sites of slow degradation in solution.
TB-500
Thymosin β4 is a 43-amino-acid protein that binds actin monomers. The name “TB-500” is used for a synthetic peptide based on its actin-binding region. Most commonly this is the acetylated 7-residue fragment Ac-LKKTETQ, although some suppliers use the name for full-length thymosin β4 (about 4963 g/mol, CAS 77591-33-4). Because the name is used loosely, check the molecular weight on the certificate of analysis to confirm which molecule you have. The fragment is highly hydrophilic, with two lysines and a glutamic acid, and dissolves readily in water.
Handling differences
- Solubility: both dissolve in sterile water or bacteriostatic water. TB-500 dissolves faster; BPC-157 may need gentle swirling.
- Calculations: the molecular weights differ by about 530 g/mol, so equal masses give different molar amounts. Use net peptide content from the CoA where available.
- Analysis: on reverse-phase HPLC the two elute at different times, which makes it straightforward to confirm both are present in a combined preparation.
- Storage: identical. Store powder at −20 °C and solutions at 2–8 °C, and avoid repeated freeze–thaw. See how to store peptides.
Combined preparations
Because their storage requirements match and they do not react with each other, BPC-157 and TB-500 are sometimes supplied together in a single vial. Our BPC-157 + TB-500 blend contains 5 mg of each. When working with a blend, confirm both components separately by MS or HPLC.
Where to buy
Peptide Pro supplies BPC-157 10 mg, TB-500 10 mg and the combined blend, dispatched from within the EU with tracked delivery.
All Peptide Pro products are supplied for laboratory and in-vitro research only. They are not medicines and are not for human or veterinary use. Nothing on this page describes or recommends use in humans or animals.