TB-500

TB-500 is a linear 17-residue peptide derived from the actin-binding region of thymosin β4. The fragment retains the parent protein's central G-actin-binding motif while omitting flanking residues — a structural simplification that has made it a workhorse in studies dissecting which sequence elements drive actin sequestration. Pharmacokinetic descriptors documented in published animal-model investigations include rapid distribution, a short systemic half-life under standard parenteral paradigms, and renal clearance as the principal elimination route. Interaction profile in the literature centers on G-actin binding, with downstream investigation of Rac1, MMP, and VEGF pathway intersection in wound-response assays. All activity descriptors here are framed as documented in published work rather than as effects of the supplied product. Structural confirmation is established by mass spectrometry molecular-ion match and HPLC-validated purity on each Certificate of Analysis.

Experimental domains documented in the published literature include actin-binding structure-activity studies, in-vitro endothelial cell migration assays, fibroblast wound-model paradigms, cardiomyocyte injury-response investigations, and corneal epithelial migration studies. Investigators have also characterized the fragment in comparative work alongside full-length thymosin β4 and other actin-binding peptides to dissect sequence-level contributions to motility signaling. Use in laboratory research extends to mechanism-elucidation paradigms where the literature frames TB-500 as a probe for cytoskeletal regulation rather than as a defined intervention. The reference standard is supplied for these and equivalent in-vitro experimental contexts only, with no associated guidance for human, clinical, or veterinary application. Researchers should consult primary literature and institutional review processes when designing context-specific protocols.

Each lot is characterized by reverse-phase HPLC for chromatographic purity and by mass spectrometry for molecular-ion confirmation against the C38H68N10O14 empirical formula. Purity is reported as an HPLC-area percentage on the Certificate of Analysis distributed with every lot, alongside the molecular-weight match within instrument tolerance. Peptide content where applicable is determined by amino-acid analysis or nitrogen-content assay following the analytical method specified on the COA. Residual solvent and water content are reported categorically when these parameters are part of the lot's release specification. The COA records the lot identifier, manufacturing date, and analytical method versions used, providing a traceable provenance chain from synthesis through release. Researchers requiring batch-level analytical detail should reference the COA distributed with the supplied material.

For laboratory storage, the lyophilized reference standard should be held at −20°C in its sealed, light-protected container until ready for analytical use. Allow vials to equilibrate to ambient temperature before opening to avoid moisture condensation on the lyophile. Reconstitution for in-vitro experimental use is typically performed in bacteriostatic water or a researcher-selected buffer compatible with the downstream assay; once reconstituted, store the working solution at 2–8°C and characterize stability in the relevant buffer prior to extended storage. Avoid repeated freeze-thaw cycles of reconstituted material — single-use aliquots are preferred for experiments where peptide integrity is assay-critical. These handling parameters reflect general best-practice for lyophilized peptide reference standards and do not constitute preparation guidance for human or veterinary application.