Buy Thymulin Research Peptide

Thymulin (CAS 63958-90-7), also known as Facteur Thymique Serique (FTS) or Serum Thymic Factor, is a naturally-occurring nonapeptide metallopeptide with a molecular weight of 858.86 g/mol. Biological activity requires coordination of a zinc ion (Zn²⁺). Defined by the amino acid sequence pGlu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn, Thymulin features an N-terminal pyroglutamyl residue and requires the coordination of a single zinc ion (Zn2+) for biological activity, a structural requirement that distinguishes it from other thymic peptides. This zinc dependency makes Thymulin one of the few naturally occurring metallopeptide hormones in the endocrine system. Produced via solid-phase peptide synthesis, Thymulin is associated with T-cell differentiation and thymic endocrine signaling.

Thymulin is a thymic hormone whose circulating concentrations correlate with zinc status in experimental models. In vitro studies have examined the zinc-dependent conformational transition underlying Thymulin activity, with research documenting that chelation of metal ions abolishes the biological activity of the serum thymic factor and that zinc restores it, establishing it at the required 1:1 metal-to-peptide molar ratio and forming the basis for the designation of the zinc-complexed form as “thymulin” [1]. In vivo rodent studies have examined circulating Thymulin concentrations in relation to zinc status, thymic involution, and age-related immune function changes, with published research documenting that oral zinc supplementation in aged mice restores active (zinc-saturated) thymulin, induces thymic regrowth, and partially restores peripheral immune function, and characterizing the age-related decline as involving both a reduced zinc saturation of thymulin and decreased thymic production [2], making Thymulin a reference compound in thymic peptide research examining the interplay between zinc coordination, metallopeptide hormone activity, and age-related thymic endocrine function.

Thymulin is produced to research-grade standards and independently verified by third-party HPLC and MS-UPLC analysis before dispatch. Vials are vacuum sealed and stored in a temperature controlled, monitored cold storage system. Certificates of Analysis are available to view and download directly on the product page.

Sold strictly for in vitro research purposes only. Not for human consumption. Intended for use by qualified researchers in laboratory settings only.

Scientific Review

Dr. Martina Rossi, PhD

Scientific Contributor and Reviewer

Reviewed for scientific accuracy, 14 June 2026

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