BPC-157 and TB-500 compared

Unrelated in sequence and origin. BPC-157 is a linear 15-residue peptide, rich in proline, with free termini. TB-500 is a seven-residue N-acetylated peptide, residues 17–23 of thymosin β4, with a free C-terminal acid. They are compared because the two are often paired in research-material blends, where each must be identified and measured on its own.

Sequences side by side

Aligned from residue 1: 0 positions identical, 7 substituted, 8 present in only one. In each column the upper residue is BPC-157's and the lower is TB-500's. Substituted positions are highlighted.

Termini and bridges also differ: N-terminus: BPC-157 free amine, TB-500 N-acetyl.

Calculated properties

Calculated from each structure

Property	BPC-157	TB-500	Difference (TB-500 − BPC-157)
Residues	15	7	−8
Molecular formula	C62H98N16O22	C38H68N10O14
Monoisotopic mass (Da)	1,418.7042	888.4916	−530.2125
Average mass (g/mol)	1,419.56	889.02	−530.54
Net charge at pH 7	-2.0	0.0	+2.0
Isoelectric point	3.88	7.36	+3.48
Hydropathy (GRAVY)	-0.69	-1.77	−1.08
ε280 (M−1 cm−1)	0	0

Telling them apart by mass spectrometry

The monoisotopic masses differ by 530.2125 Da, which any routine mass spectrometer resolves.

Expected protonated ions (monoisotopic m/z)

Ion	BPC-157	TB-500
[M+H]+	1,419.7114	889.4989
[M+2H]2+	710.3594	445.2531
[M+3H]3+	473.9087	297.1712

Telling them apart by HPLC

They differ greatly in size (15 and 7 residues), so their reversed-phase retention cannot be estimated from average hydropathy; size, charge and the residues at the ends all contribute. They are usually well separated. Retention depends on the whole molecule and on the method, so the order is confirmed by running both, or by mass spectrometry of each peak.

Analytical variants each can form

The sequence-specific variants from each entry. A variant only one of them can form is a quick way to tell which is which, and a reminder of what to look for in each.

Sequence-specific variants

Variant	Mass change	BPC-157	TB-500
Glutamine deamidation	+0.984 Da	No	Yes

Full details, with isotope patterns and fragment ions, are on each entry: BPC-157 and TB-500.

Sources & Further Reading

1. Prohaska T, Irrgeher J, Benefield J, Böhlke JK, Chesson LA, Coplen TB, et al. Standard atomic weights of the elements 2021 (IUPAC Technical Report). Pure and Applied Chemistry 2022;94(5):573–600. doi:10.1515/pac-2019-0603
2. Wang M, Huang WJ, Kondev FG, Audi G, Naimi S. The AME 2020 atomic mass evaluation (II). Tables, graphs and references. Chinese Physics C 2021;45(3):030003. doi:10.1088/1674-1137/abddaf
3. Rice P, Longden I, Bleasby A. EMBOSS: the European Molecular Biology Open Software Suite. Trends in Genetics 2000;16(6):276–277. doi:10.1016/S0168-9525(00)02024-2
4. Pace CN, Vajdos F, Fee L, Grimsley G, Gray T. How to measure and predict the molar absorption coefficient of a protein. Protein Science 1995;4(11):2411–2423. doi:10.1002/pro.5560041120
5. Kyte J, Doolittle RF. A simple method for displaying the hydropathic character of a protein. Journal of Molecular Biology 1982;157(1):105–132. doi:10.1016/0022-2836(82)90515-0
6. Meija J, Coplen TB, Berglund M, Brand WA, De Bièvre P, Gröning M, et al. Isotopic compositions of the elements 2013 (IUPAC Technical Report). Pure and Applied Chemistry 2016;88(3):293–306. doi:10.1515/pac-2015-0503
7. Roepstorff P, Fohlman J. Letter to the editors: proposal for a common nomenclature for sequence ions in mass spectra of peptides. Biomedical Mass Spectrometry 1984;11(11):601. doi:10.1002/bms.1200111109
8. Biemann K. Contributions of mass spectrometry to peptide and protein structure. Biomedical and Environmental Mass Spectrometry 1988;16(1–12):99–111. doi:10.1002/bms.1200160119
9. Geiger T, Clarke S. Deamidation, isomerization, and racemization at asparaginyl and aspartyl residues in peptides. Succinimide-linked reactions that contribute to protein degradation. Journal of Biological Chemistry 1987;262(2):785–794. doi:10.1016/S0021-9258(19)75855-4
10. Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharmaceutical Research 2010;27(4):544–575. doi:10.1007/s11095-009-0045-6
11. D'Hondt M, Bracke N, Taevernier L, Gevaert B, Verbeke F, Wynendaele E, et al. Related impurities in peptide medicines. Journal of Pharmaceutical and Biomedical Analysis 2014;101:2–30. doi:10.1016/j.jpba.2014.06.012

Cosmic Peptides. (2026, October 25). BPC-157 and TB-500 compared. Cosmic Peptides Research Library. Retrieved November 2, 2026, from https://cosmicpeptides.com/research/peptides/compare/bpc-157-vs-tb-500

@misc{cosmicpeptides_research_peptides_compare_bpc_157_vs_tb_500,
  author       = {{Cosmic Peptides}},
  title        = {BPC-157 and TB-500 compared},
  howpublished = {Cosmic Peptides Research Library},
  year         = {2026},
  month        = oct,
  url          = {https://cosmicpeptides.com/research/peptides/compare/bpc-157-vs-tb-500},
  urldate      = {2026-11-02},
  note         = {Last reviewed 2026-10-25}
}

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