We report net peptide content, not just purity — so the milligrams you dose aren't padded with water and counter-ion. RP-HPLC purity and ESI-MS identity, on a lot-numbered COA.
Net peptide content, not just purity — RP-HPLC + ESI-MS, lot-numbered COA.
Net peptide content on every lot's COA.
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28-amino-acid thymic immune-modulation peptide
Lyochem primary owner
This Lyochem page is the primary SEO owner for research labs, CROs, and method-development teams qualifying Thymosin Alpha-1 (Thymalfasin) as a documented research-standard lot. The page should answer whether the buyer can review HPLC purity, identity confirmation, lot continuity, stability handling, and assay-fit documentation before ordering.
Overview
Thymosin Alpha-1 (Thymalfasin; marketed as Zadaxin) is a 28-residue, N-terminally acetylated immunomodulatory peptide, originally recovered from bovine thymus and now made synthetically. Mechanistically it drives T-cell maturation and function via TLR-9-dependent dendritic-cell activation and additionally modulates NK-cell and macrophage activity, the pharmacology that underpins both its antiviral and immune-restoration research interest. Regulatory status is unusual for a peptide of this size: it is an approved prescription biological in more than 35 jurisdictions, among them China, Italy, India, and several Southeast Asian markets, with indications spanning chronic hepatitis B, chronic hepatitis C in combination regimens, and use as a vaccine adjuvant. Lyochem supplies Thymosin Alpha-1 as a lyophilized reference standard at ≥99.0% HPLC purity. At 28 residues the chain is well within dependable SPPS range, and the N-terminal acetyl group is verified by ESI-MS as a +42 Da shift against the unacetylated peptide. Given its approved-drug status across many markets, we build extra depth into each lot's release documentation, which pairs the HPLC chromatogram and mass spec with counter-ion and water-content figures and, on request, adds microbial limits plus endotoxin (LAL) testing. Fills of 5 mg and 10 mg. Lyochem furnishes the material strictly for research use only.
Applications & buyer fit
Buyers in this category are research labs studying immune-modulation, cytokine signalling, and antimicrobial activity. The defining QC requirement is bacterial-endotoxin control: many downstream assays (NF-κB reporters, macrophage-activation panels, neutrophil-priming readouts) are themselves activated by endotoxin contamination, so a clean LAL on the specific lot is a precondition rather than a nice-to-have. LL-37 and related cationic antimicrobial peptides additionally benefit from low-bind plasticware during dilution.
Biotech R&D Groups
Preclinical biotech and pharmaceutical discovery teams sourcing characterized peptides for receptor-pharmacology, screening, and method-development campaigns.
Academic Laboratories
Universities, medical schools, and government research institutes qualifying a reference standard for a method-development or in vivo workflow.
Every release ships with its own batch-specific CoA — identity, purity, and the analytical scope agreed at quote stage, tied to the exact lot you receive.
Review a representative batch CoA before you order, so you can confirm the packet matches what your method or sponsor audit needs.
Supplied strictly as a research reagent to research institutions — not a finished dosage form and not for human administration. Buyer qualification runs at the inquiry stage.
Specifications
Documentation available on request
Regulatory note
Across more than 35 jurisdictions — among them China, Italy, India, and several APAC markets — this is approved as a prescription biological, marketed as Zadaxin or as generic equivalents. As of this writing it is not approved in the US or EU, and sales are limited to qualified buyers who hold appropriate licensing in their jurisdiction.
Selected literature
Frequently asked questions
The acetyl group adds 42 Da to the 28-residue backbone, so an ESI-MS value near the theoretical 3108 Da, read as a +42 Da shift from the unacetylated form, is the diagnostic identity check and separates correctly capped material from an incompletely modified variant. Mass alone does not resolve every same-mass by-product, so at first-time supplier qualification LC-MS/MS fragment coverage is added to read the residue order. The acetylation is thus confirmed both as an intact-mass offset and, where needed, as a localized N-terminal feature in the fragmentation data.
The 28-residue sequence carries several Asp and Glu residues, and their deamidation by-products elute very close to the target on RP-HPLC, so a chromatogram that looks clean can still hide near-co-eluting variants. Sequence-level LC-MS/MS is therefore recommended at qualification to distinguish the intended molecule from these closely related species. For in vivo or immune-cell readouts the bacterial endotoxin (LAL) test is strongly advised, because those assays are themselves activated by endotoxin; for purely in vitro biochemical work the LAL step is optional.
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