{"id":492,"date":"2026-09-06T21:45:29","date_gmt":"2026-09-06T21:45:29","guid":{"rendered":"https:\/\/premiumpeptide.shop\/research\/compounds\/tb-500\/"},"modified":"2026-09-06T21:59:33","modified_gmt":"2026-09-06T21:59:33","slug":"tb-500","status":"publish","type":"page","link":"https:\/\/premiumpeptide.shop\/en\/research\/compounds\/tb-500\/","title":{"rendered":"TB-500 (Thymosin beta-4)"},"content":{"rendered":"

TB-500 is a trade designation that is used inconsistently in the peptide trade. For analytical work that is precisely the central point: the name alone does not determine the molecular mass.<\/p>\n

What is TB-500?<\/h2>\n

The designation TB-500 refers to thymosin beta-4 or to its actin-binding region. Thymosin beta-4 is a naturally occurring polypeptide of 43 amino acids with N-terminal acetylation and an average molecular mass of approximately 4.9 kDa. The short sequence Leu-Lys-Lys-Thr-Glu-Thr-Gln (LKKTETQ) is described as the actin-binding motif, a heptapeptide with a molecular mass in the range of approximately 0.9 kDa.<\/p>\n

Both variants are traded under the designation TB-500: on the one hand the complete acetylated thymosin beta-4, on the other the short fragment. The two substances differ by more than a factor of five in mass. A product designation without a sequence or mass figure is therefore not analytically unambiguous.<\/p>\n

Research context<\/h2>\n

Thymosin beta-4 is described in the cell biology literature as an actin-sequestering protein and has been the subject of preclinical investigations. An approved medicinal product does not exist. For research and comparison purposes it is relevant that publications on thymosin beta-4 cannot readily be transferred to preparations that contain only the heptapeptide motif. Which variant is actually present can only be clarified analytically.<\/p>\n

Analytical identification<\/h2>\n

With TB-500 the mass determination is the decisive step, not the chromatography:<\/p>\n