Thymosin Alpha-1 – 10mg

Thymosin Alpha-1 is a synthetic 28-amino-acid peptide first characterized from calf thymus extract, and it remains one of the most studied thymic peptides in the published immune-signaling literature. Laboratories that buy thymosin alpha-1 research peptide from First Class Science are typically running in vitro or animal-model protocols examining dendritic-cell activation, T-cell signaling, and innate-immune receptor pathways. This page is a research-reference summary for laboratory professionals sourcing this compound — it is not a guide to human or animal use, and nothing below describes an intended therapeutic effect of this product.

In this reference:

• What Is Thymosin Alpha-1?
• Proposed Mechanism of Action
• Chemical Identity
• Purity, Storage & Quality
• Research Applications
• What the Human Evidence Shows
• Compared to Related Research Compounds
• Frequently Asked Questions

What Is Thymosin Alpha-1?

Thymosin Alpha-1 (TA1) was first isolated as an active component of Thymosin Fraction 5, a thymic extract studied by researchers including Allan Goldstein in the 1970s as part of a broader effort to identify thymus-derived peptides involved in immune-cell development. Since that original characterization, TA1 has become a frequently cited subject in published immunology literature examining innate and adaptive immune-signaling pathways in cell-culture and animal models.

It is important for researchers to understand exactly what this product is, and is not. Under the brand name Zadaxin, a synthetic version of this same peptide sequence (thymalfasin) has been approved as a prescription immunomodulator in roughly 30 countries outside the United States, generally in combination with interferon for chronic hepatitis B or as a chemotherapy adjunct (Tao et al., Molecules, 2023).

Thymosin Alpha-1 is not FDA-approved and has no approved drug status of any kind in the United States. The material sold on this page is supplied strictly for laboratory research use, is not the approved foreign drug product, is not evaluated by the FDA, and is not intended to diagnose, treat, cure, or prevent any disease in any person or animal.

Because TA1’s research base spans both a large preclinical literature and an unusually developed international clinical-use history, researchers sourcing this compound should treat the two evidence tracks separately. The sections below summarize the mechanistic and preclinical literature first, then address the international clinical-use history directly in its own section further down this page.

Laboratories that buy thymosin alpha-1 research peptide typically do so to run comparative dendritic-cell or T-cell signaling assays alongside other innate-immune research compounds already in their protocol library. Because TA1’s mechanistic literature spans several distinct receptor pathways, many research groups source it specifically to test which of those proposed pathways is active in their own cell-culture model, rather than to replicate a single prior finding outright.

Proposed Mechanism of Action

Published research describes TA1 as acting across multiple arms of the immune system rather than through a single defined receptor. A 2023 review in Molecules reports that TA1 engages Toll-like receptors TLR3, TLR4, and TLR9 on dendritic cells, activating downstream IRF3 and NF-κB signaling, with additional activity proposed through TLR2/NF-κB, TLR2/p38 MAPK, and TLR7/MyD88 pathways that researchers link to cytokine-production changes in treated cell models (Tao N, et al. “Thymosin α1 and Its Role in Viral Infectious Diseases: The Mechanism and Clinical Application.” Molecules. 2023;28(8):3539 — PMC10144173).

A separate review in Vitamins & Hormones describes TA1’s reported effects on dendritic-cell maturation markers (including CD40 and CD80 upregulation, with reduced PD-L1 expression) and on T-cell subsets, where cultured CD4+ and CD8+ populations exposed to TA1 showed altered TNF-α, IFN-γ, and IL-2 production relative to untreated controls (King R, Tuthill C. “Immune Modulation with Thymosin Alpha 1 Treatment.” Vitamins & Hormones. 2016;102:151-178). Study authors describe this as a pleiotropic signaling profile affecting several immune-cell subsets simultaneously, rather than a single confirmed molecular target.

Researchers should treat every mechanistic claim summarized here as a proposed explanation drawn from specific published cell-culture or animal studies, not as an established pharmacological fact about this research-use product.

Chemical Identity

CAS Number	62304-98-7
Molecular Formula	C129H215N33O55
Molecular Weight	~3,108.3 g/mol
Sequence Length	28 amino acids
Appearance	White to off-white lyophilized powder

Full compound data: PubChem CID 16130571 (pubchem.ncbi.nlm.nih.gov/compound/16130571)

Purity, Storage & Quality

Researchers who buy thymosin alpha-1 research peptide from First Class Science receive material tested to confirm identity and purity at research grade, with a Certificate of Analysis available for every batch at our Certificate of Analysis page, listing the specific lot’s purity result, molecular-weight confirmation, and test date.

Store the lyophilized (freeze-dried) compound at −20°C for long-term stability. After reconstitution with bacteriostatic or sterile water, refrigerate at 2–8°C and use within 4–6 weeks. Avoid repeated freeze-thaw cycles and prolonged exposure to light or room-temperature conditions, both of which are associated with accelerated peptide degradation in handling literature.

Important: This item is manufactured strictly for research purposes. It is not intended for human or veterinary use and is distributed solely for laboratory and scientific investigation.

Quality Control Methodology

Each production batch of this thymosin alpha-1 research peptide undergoes independent third-party testing before release. High-performance liquid chromatography (HPLC) is used to confirm purity by measuring the proportion of the target peptide relative to any synthesis by-products or degradation fragments in the sample. Mass spectrometry separately confirms molecular identity, verifying that the measured mass of the material matches the expected ~3,108.3 g/mol molecular weight of TA1. Both results are recorded on the batch’s published Certificate of Analysis, allowing researchers to independently verify identity and purity rather than relying on manufacturer claims alone.

Preparing Solutions for Laboratory Use

Laboratories reconstituting lyophilized TA1 for in vitro assay use typically follow standard peptide-handling practice: the vial is brought to room temperature before opening, and a diluent — commonly reconstitution solution or sterile water for injection (SWFI) — is added slowly down the interior vial wall rather than directly onto the lyophilized material, to reduce foaming and mechanical stress on the peptide. The vial is then gently swirled, never shaken, until fully dissolved. Stock-solution concentration is calculated by dividing total peptide mass by diluent volume, and that calculation should be recorded in protocol documentation. This describes general laboratory reconstitution practice for research use only and is not a dosing guide for human or animal administration.

Why Researchers Buy Thymosin Alpha-1 Research Peptide Here

Buyers of this thymosin alpha-1 research peptide are university and academic research laboratories, contract research organizations (CROs), and biotechnology R&D teams running in vitro and animal-model studies on innate-immune signaling and dendritic-cell/T-cell pathways. First Class Science requires that all research-peptide orders be placed by parties who acknowledge and agree to the research-use-only terms stated on this page prior to purchase. Institutional buyers frequently request the Certificate of Analysis for a specific lot in advance for their own internal quality-assurance records, which First Class Science makes available on request.

Research Applications

The published literature on TA1 spans several distinct research areas. Each is summarized below strictly as a description of what has been studied in cell-culture and animal models, or in the separate international clinical-use context discussed later on this page — never as a claim about the effects of this research-use product in a person or animal.

Innate & Adaptive Immune-Signaling Research

Cell-culture research has examined TA1’s association with Toll-like-receptor activation on dendritic cells and downstream cytokine production in both innate and adaptive immune-cell populations, as summarized in the mechanism section above. This remains the most consistently replicated research area for the compound across published in vitro models. Laboratories that buy thymosin alpha-1 research peptide for this specific research line typically pair it with flow-cytometry panels designed to track CD40, CD80, and PD-L1 marker changes across treated versus untreated dendritic-cell cultures, allowing direct comparison against the marker shifts reported in the published literature cited above.

Viral-Infection Research Models

A substantial body of published research, much of it conducted outside the United States, has examined TA1 in models and clinical-research populations related to chronic hepatitis B and C, with study authors reporting associations between TA1 exposure and immune-cell activation measures (Tao et al., 2023). This literature is discussed strictly as published third-party research and international clinical history; it does not describe an intended use of this laboratory research product.

Oncology-Adjuvant Research

Separate published research has examined TA1 as an adjunct compound alongside chemotherapy or immune-checkpoint-targeted research agents in oncology study models, with researchers reporting changes in immune-cell counts and markers of immune competence in the populations studied (King & Tuthill, 2016). Study authors describe this as an active but still-developing research area.

Vaccine-Response & Critical-Illness Immune-Recovery Research

Additional published literature has examined TA1’s association with vaccine-response measures and, in critical-illness and sepsis research models, with immune-marker recovery. Study authors describe this as an early-stage area of investigation with fewer independent replications than the dendritic-cell and viral-infection literature above.

What the Human Evidence Shows

Thymosin Alpha-1 has an unusually developed international clinical-use history relative to many research peptides. Under the brand name Zadaxin, the synthetic thymalfasin form of this peptide sequence is approved in roughly 30 countries as a prescription immunomodulator, generally for chronic hepatitis B, often alongside interferon, and in some markets as a chemotherapy adjunct (Tao et al., Molecules, 2023).

This international approval and clinical-trial history does not extend to the United States, and it does not apply to the material sold on this page. Thymosin Alpha-1 has never been approved by the FDA for any indication, and this product is not the approved Zadaxin drug formulation. It is manufactured and sold exclusively as a research chemical, is not evaluated by the FDA, and carries none of the manufacturing controls, prescribing oversight, or clinical indications that apply to an approved drug product in any jurisdiction.

We include this section because researchers deserve an accurate picture of the evidence base. The published clinical literature behind Zadaxin’s foreign approvals is real and well-documented; it is equally real that this research-use compound is a separate, non-clinical-grade product, distributed strictly for laboratory investigation and not for administration to any person or animal in any context, treatment-related or otherwise.

Compared to Related Research Compounds

TA1 is frequently studied alongside other immune- and repair-signaling research peptides. First Class Science supplies several related preparations for researchers running comparative studies:

LL-37 – 10mg is a cathelicidin-family antimicrobial peptide studied for its innate-immune and antimicrobial-signaling activity in cell-culture models, giving researchers a second innate-immune-pathway compound alongside TA1 for comparative immune-signaling protocols.

TB-500 (Thymosin Beta-4) – 10mg is a distinct thymosin-family peptide studied in tissue-repair and cell-migration research contexts rather than the dendritic-cell/T-cell signaling pathways associated with TA1, useful for laboratories comparing thymosin-family peptides across different research applications.

TB-500 Capsules – 500mcg supplies the same Thymosin Beta-4 sequence in an oral-research format, for laboratories whose protocols call for oral-route rather than reconstituted-solution administration models.

Each of these related preparations carries its own Certificate of Analysis and is subject to the same research-use-only terms described on this page. Laboratories choosing between TA1, LL-37, and TB-500 typically base that decision on the specific immune or repair pathway their protocol targets, since each peptide’s published literature centers on a distinct signaling mechanism.

Common Research Study Designs

Published studies referenced throughout this page typically fall into one of several designs: in vitro cell-culture assays examining a specific dendritic-cell or T-cell signaling pathway in isolation; controlled animal models comparing treated and untreated groups on a defined immune-marker outcome; and, in TA1’s case, a separately-documented international clinical-use and trial history behind its foreign Zadaxin approvals. Researchers citing findings from this page should identify which of these three evidence categories a given claim comes from, since a cell-culture finding, an animal-model finding, and a foreign clinical-trial finding carry very different evidentiary weight and none of them describe an approved use for this research-only product.

Documentation & Certificate of Analysis Requests

Institutional buyers who purchase thymosin alpha-1 research peptide for a funded protocol frequently need batch-specific documentation before a purchase order can be approved internally. First Class Science publishes a Certificate of Analysis for every batch and can provide the specific lot documentation for a given order on request, including HPLC purity results and mass-spectrometry molecular-weight confirmation, so that a receiving lab’s own quality-assurance process can independently verify the material before it enters a study.

Frequently Asked Questions

What is the purity of this thymosin alpha-1 research peptide?
Every batch is tested to confirm identity and purity at research grade, with a Certificate of Analysis published for each lot.

How should thymosin alpha-1 research peptide be stored?
Store the lyophilized powder at −20°C. After reconstitution, refrigerate at 2–8°C and use within 4–6 weeks; avoid repeated freeze-thaw cycles.

Is thymosin alpha-1 approved for human or animal use?
Not in the United States. A synthetic version (thymalfasin/Zadaxin) is approved in roughly 30 other countries for chronic hepatitis B and as a chemotherapy adjunct, but this US-market product is not that drug, is not FDA-approved, and is sold exclusively for laboratory research.

Where can I buy thymosin alpha-1 research peptide with verified purity?
First Class Science supplies this thymosin alpha-1 research peptide with third-party-verifiable testing and a published Certificate of Analysis for every batch, for researchers who require documented purity and identity before beginning a protocol.

How does TA1 differ from TB-500 (Thymosin Beta-4)?
Both are thymosin-family peptides, but TA1’s published literature centers on dendritic-cell and T-cell immune-signaling pathways, while TB-500’s centers on cell-migration and tissue-repair research. They are studied in different research contexts and are not interchangeable in a protocol.

Does the research on TA1 include human clinical trials?
Yes, but only for the separately-manufactured, foreign-approved Zadaxin drug product, not for this research-use compound. See “What the Human Evidence Shows” above for the distinction.

Can thymosin alpha-1 research peptide be shipped internationally?
Shipping availability and any import restrictions for research peptides vary by destination country and are subject to change; researchers should confirm their local import regulations for research-use-only compounds before ordering.

What documentation comes with an order?
Every order of this thymosin alpha-1 research peptide includes access to the batch-specific Certificate of Analysis, and institutional buyers may request additional lot documentation directly from customer support for internal QA records.

Shipping, Handling & Compliance

This thymosin alpha-1 research peptide ships as a lyophilized powder in a sealed glass vial, packaged to maintain cold-chain integrity in transit where applicable. All orders are subject to the research-use-only terms stated on this page, and First Class Science does not sell this or any other research peptide for human or veterinary administration under any circumstance. Order tracking, batch-specific documentation requests, and general product questions can be directed to First Class Science customer support, which can confirm current lead times and any destination-specific documentation a receiving institution may require for its own compliance records.

Disclaimer: The research summarized above is drawn from third-party published studies conducted in animal, in vitro, or clinical research contexts. It is provided for research and educational reference only and does not describe an intended use, effect, or benefit of this product for any person or animal.

⊗ ALL ITEMS ARE SOLD FOR RESEARCH USE ONLY. This category covers strictly in vitro laboratory testing and scientific experimentation. Content on this site is for education only and does not authorize human or animal use of any kind, which is prohibited by law. Only trained, licensed professionals should handle these materials. Nothing sold here qualifies as a drug, food, or cosmetic, and none of it may be labeled, advertised, or used as such.