TB-500 in Research: Material Properties, Analytical Standards, and Canadian Sourcing

TB-500 is a synthetic peptide fragment derived from Thymosin Beta-4 (Tβ4) — a naturally occurring 43-amino acid protein involved in actin sequestration and cell migration. As a research material, TB-500 is studied in the context of tissue repair models, wound healing studies, and cellular migration assays.

This article covers the material's structural properties, how it should be analytically verified, and what Canadian researchers should confirm before sourcing it.

All content is informational and applies to laboratory and analytical research contexts only. This material is for research use only and is not intended for human or animal use.

Structural Overview

TB-500 refers specifically to the actin-binding domain fragment of Thymosin Beta-4 — the sequence Ac-SDKPDMAEIEKFDKSKLKKTETQ, corresponding to residues 17–23 of the full protein in its bioactive region.

• Molecular formula: C₁₂₁H₂₀₀N₃₄O₃₉S
• Molecular weight: ~2888.2 Da (average); ~2886.4 Da (monoisotopic)
• Amino acid count: 23 residues (as the active fragment)
• Presentation: Lyophilized powder
• Solubility: Soluble in water and aqueous buffers

TB-500 is not an approved pharmaceutical. It is not authorized for human or veterinary use in Canada or most other jurisdictions. Its research use is confined to qualified laboratory settings.

Research Applications

Published literature involving TB-500 and Thymosin Beta-4 includes studies in the following contexts:

• Cardiac tissue repair models (animal studies)
• Corneal wound healing models
• Skin repair and keratinocyte migration assays
• Tendon and muscle repair models
• Neuronal regeneration models

This body of research is preclinical. It does not establish safety or efficacy for human use, and researchers should not apply clinical assumptions to their experimental designs based on this literature.

Analytical Verification

The same documentation standards that apply to all research peptides apply to TB-500. The two properties that must be independently verified are identity and purity.

Identity Confirmation

TB-500's molecular weight of ~2888 Da is within the standard range for LC-MS verification. Identity should be confirmed by:

• LC-MS or ESI-MS (Electrospray Ionization Mass Spectrometry): The observed m/z (mass-to-charge ratio) values across charge states should match the expected molecular weight within acceptable instrument tolerance (typically ±0.1 Da on high-resolution instruments).
• N-terminal sequencing or amino acid analysis can provide additional confirmation where mass spectrometry alone is inconclusive.

Because TB-500 contains an acetylated N-terminus (Ac-), the mass spectrometry result must account for the acetyl modification (+42.01 Da). A CoA that does not reference the acetylated form may be documenting the incorrect structure.

Purity Assessment

Purity is assessed by RP-HPLC, typically:

• Column: C18 reverse-phase column
• Detection: UV at 220 nm (peptide bond absorption)
• Reported purity: Percentage of target peak area relative to all detected peaks

Research-grade TB-500 is generally expected to achieve ≥98% purity by HPLC. Materials below this threshold should be treated as lower quality and may introduce confounding variables in sensitive assays.

What the CoA Should Include

For TB-500 specifically:

• Molecular formula (C₁₂₁H₂₀₀N₃₄O₃₉S) and stated molecular weight
• Confirmation that the acetylated form is being documented
• Lot number traceable to the specific batch received
• LC-MS identity result with observed vs. theoretical mass
• HPLC purity result with a numerical percentage
• Testing laboratory name and analysis date

Storage and Handling

Lyophilized TB-500 is stable when stored dry at −20°C, protected from light. Under these conditions, the material maintains integrity for extended periods.

Reconstitution guidance:

• Reconstitute with sterile water or an appropriate aqueous buffer
• Use the minimum volume needed to achieve the desired working concentration
• Aliquot immediately after reconstitution to avoid repeated freeze-thaw cycles
• Reconstituted peptide should be stored at −80°C for short-term use

Note: These are general research handling guidelines. Researchers should follow their institution's standard operating procedures for peptide handling and storage.

Canadian Sourcing Considerations

TB-500 is available through multiple Canadian suppliers, but documentation quality varies significantly. Several considerations specific to TB-500:

Verify the acetylated form: Some suppliers list TB-500 without specifying whether the N-terminus is acetylated. The acetylated form (Ac-SDKPDMAEIEKFDKSKLKKTETQ) is the standard research material. Non-acetylated TB-500 has a different molecular weight and potentially different properties. Confirm with the supplier which form is being supplied.

Lot-specific CoA: Request a CoA tied to the specific lot number you are ordering. Catalogue-level documentation does not confirm that the batch in your shipment meets specification.

Mass spectrometry result: For a compound at 2888 Da, LC-MS or ESI-MS is the appropriate identity method. Suppliers who cannot provide a mass spectrometry result for TB-500 are relying on purity data alone — which does not confirm identity.

Summary

TB-500 is available through Elysium Bio Labs as a lyophilized research material for qualified laboratory and analytical applications. All materials are presented for research use only and are not intended for human or animal use. Documentation is published at the batch level when verified records are available.