What is thymalin, and what does its certificate actually identify?

What is the structure of Thymalin?

Two things carry the name. Thymalin the preparation is an extract of mixed short peptides with no single formula. Thymulin is a nonapeptide with an N-terminal pyroglutamate, active only when it binds a zinc ion, PubChem CID 71300623, mass 858.9. The certificate for lot THYM20-0318 reports 858.8 by MALDI-MS, which is the mass of thymulin and not of any mixture; the product page leaves the identifier fields blank because the catalogue name and the measured molecule do not agree, and the thymalin-versus-thymulin post sets out the question.

Identifier	Value
Molecular formula	not recorded
Molecular weight	not recorded
Residues	not recorded
CAS number	not recorded
PubChem CID	not recorded
Current lot	THYM20-0318

How is Thymalin thought to work?

Thymulin, characterised by Bach and colleagues in 1977, is secreted by thymic epithelial cells and promotes T-cell differentiation in a zinc-dependent manner; the zinc-free peptide is inactive in the assays that defined it. The thymalin preparation's reported effects in the bioregulator literature are on immune indices in cells and aged animals, by mechanisms the group attributes to gene-expression regulation.

Which research areas use Thymalin?

Area	Typical models and endpoints
Thymic hormone assays	Rosette-formation and T-cell differentiation assays in which thymulin activity was originally defined.
Zinc dependence	Metal-binding and activity studies of the nonapeptide.
Immune indices in aged animals	Rodent work from the bioregulator programme on the extract.
Analytical identity	A case study in reading a certificate mass against a product name.

What does the published literature show?

Bach, Dardenne, Pleau and Rosa characterised the serum thymic factor, later named thymulin, in Nature in 1977. Khavinson and Morozov's 2003 report and Anisimov and Khavinson's 2010 review describe the thymalin preparation in the bioregulator programme. No product under either name is approved by the FDA; research use is in-vitro and preclinical.

How is Thymalin handled in the laboratory?

Dissolves in water. A pyroglutamate N-terminus and an asparagine make deamidation the slow degradation route; keep solutions cold and near neutral. Thymulin's activity in the classical assays requires zinc, so note the zinc content of any buffer. Store lyophilized at minus 20 °C; aliquot and freeze. The concentration table covers volumes and syringe units; the storage guide covers stability by compound class.

What does the current certificate show?

Lot THYM20-0318 tested at 99.8% purity by RP-HPLC (214 nm), identity confirmed by MALDI-MS, endotoxin ≤0.05 EU/mL. The certificate is in the COA library and the lot number on the vial matches it. Sold as 20 mg per vial at $70, for laboratory research only.

Certificate history for Thymalin

Every certificate the library holds for this compound, newest first. A replaced lot stays listed so the history can be read; the certificate dataset reads all 114 together.

Frequently asked questions

References

1. Bach JF, Dardenne M, Pleau JM, Rosa J. Biochemical characterisation of a serum thymic factor. Nature. 1977;266(5597):55-57.
2. Khavinson VK, Morozov VG. Peptides of pineal gland and thymus prolong human life. Neuro Endocrinol Lett. 2003;24(3-4):233-240.
3. PubChem CID 71300623, Thymulin. National Library of Medicine. Read 2 October 2026.

Clinical results cited above describe regulated trials of pharmaceutical products and are given as context for research interest only. Nothing on this page describes or recommends use of the material sold here in humans or animals.