Product Usage: For Research Use Only – Not for Human or Veterinary Use

This product is not a drug, food, cosmetic, or dietary supplement and has not been evaluated by the FDA. It is strictly intended for in vitro research by qualified professionals. Any use in humans or animals is strictly prohibited and may violate federal, state, or local laws, including the Federal Food, Drug, and Cosmetic Act. No therapeutic or diagnostic application is implied or permitted. The purchaser assumes all responsibility for compliance with applicable regulations.

TB-500 research vial

TB-500 (Thymosin Beta-4) – 10mg

10mg, lyophilized — must be reconstituted. TB-500 (Thymosin Beta-4) is a synthetic version of a naturally occurring 43-amino-acid peptide that research has examined for its interaction with actin-binding and tissue-repair signaling in laboratory models. Supplied at research-grade purity for laboratory use only.

$175.00

Researchers who buy TB-500 research peptide are typically studying its behavior as a synthetic version of Thymosin Beta-4 (Tβ4), a 43-amino-acid protein first isolated from calf thymus tissue and since found broadly distributed across mammalian tissue and blood platelets. Tβ4 is best characterized in the biochemistry literature as the primary intracellular actin-sequestering protein in most cells. The summary below reflects the published preclinical and clinical literature and is provided strictly for research and educational reference — it does not describe an intended effect of this product in humans or animals.

Buy TB-500 (Thymosin Beta-4) research peptide 10mg vial by First Class Science

In this reference:

What Is TB-500 (Thymosin Beta-4)?

TB-500 is the common research designation for a synthetic version of Thymosin Beta-4 (Tβ4), a 43-amino-acid polypeptide encoded by the TMSB4X gene and one of the most abundant intracellular peptides in mammalian cells. It is expressed broadly across tissue types and is best characterized in the published biochemistry literature as the primary actin-sequestering protein in the cell, regulating the balance between monomeric (G-actin) and filamentous (F-actin) actin available for cytoskeletal assembly.

The foundational characterization of this activity was published by Safer, Elzinga, and Nachmias, who demonstrated that Tβ4 (referred to in earlier literature under the synonym “Fx peptide”) sequesters G-actin and is functionally indistinguishable from the previously described actin-sequestering peptide Fx (J Biol Chem. 1991;266(7):4029-4032; PMID 1999398). That actin-regulatory role is the basis for essentially all downstream research interest in Tβ4 biology, including the cell-migration and tissue-repair research summarized below.

Researchers should note a naming distinction: “TB-500” is a research-community shorthand, not a formal biochemical name. It refers to synthetic material intended to correspond to Thymosin Beta-4. Published peer-reviewed literature on this biology is indexed under “Thymosin Beta-4” or “Tβ4,” not under the vendor name “TB-500” — researchers searching the primary literature should use the biological name.

Proposed Mechanism of Action

The principal, well-established mechanism of Tβ4 is high-affinity, 1:1 binding to monomeric G-actin, which prevents premature polymerization and regulates the size of the actin monomer pool available to the cell (Safer et al., 1991, PMID 1999398). By controlling this pool, Tβ4 has been studied as a regulator of actin-filament assembly and disassembly dynamics that underlie cell shape, motility, and mechanosensing.

Building on this core mechanism, published preclinical research has proposed several downstream research threads: modulation of keratinocyte, endothelial-cell, and fibroblast migration rates in scratch-wound and transwell migration assays; upregulation of angiogenic signaling (including VEGF-related pathways) in tissue-injury animal models; and reduced expression of select inflammatory-cytokine markers in tested wound and injury models. Study authors have also proposed an interaction between Tβ4 and integrin-linked kinase (ILK), a signaling node connecting the extracellular matrix to intracellular pathways governing cell survival and growth-factor response.

No single downstream pathway has been exhaustively mapped across every tissue type studied, and researchers should treat the mechanisms above as findings specific to the cited study models, not a complete pharmacological account. Receptor and pathway engagement can vary meaningfully by tissue and species, which is part of why comparative research on this protein continues across cardiac, dermal, corneal, and musculoskeletal injury models.

Chemical Identity

CAS Number 77591-33-4
Molecular Formula C212H350N56O78S
Molecular Weight ~4963.4 g/mol
Sequence Length 43 amino acids
Appearance White to off-white lyophilized powder

Purity, Storage & Quality

First Class Science supplies this TB-500 (Thymosin Beta-4) research peptide vial at research-grade purity, verified by independent third-party HPLC testing and mass spectrometry. A Certificate of Analysis is 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. This vial must be reconstituted with bacteriostatic or sterile water before laboratory use; after reconstitution, 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.

Preparing Solutions for Laboratory Use

Laboratories reconstituting lyophilized TB-500 for in vitro or animal-model research 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 wall of the vial 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 the powder is fully dissolved.

Stock-solution concentration for a given protocol is calculated by dividing the total peptide mass in the vial by the volume of diluent added, and that calculation should be recorded in the study’s protocol documentation. This page describes general laboratory reconstitution practice for research use and is not a dosing guide for human or animal administration.

Quality Control Methodology

Each production batch of this TB-500 research peptide undergoes independent third-party testing before release. High-performance liquid chromatography (HPLC) confirms purity by measuring the proportion of the target peptide relative to synthesis by-products or degradation fragments. Mass spectrometry separately confirms molecular identity, verifying that the measured mass of the material matches the expected ~4963.4 g/mol molecular weight of Tβ4. Both results are recorded on the batch’s published Certificate of Analysis, letting researchers independently verify identity and purity rather than relying on manufacturer claims alone.

Who Should Buy TB-500 Research Peptide

Researchers who buy TB-500 from First Class Science are typically university and academic laboratories, contract research organizations (CROs), and biotechnology R&D teams running cell-migration assays or animal-model studies on cytoskeletal regulation, wound biology, or angiogenic signaling. 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.

Research Applications

The published literature on Thymosin Beta-4 spans several distinct research areas. Each is summarized below strictly as a description of what has been studied in animal, in vitro, or controlled clinical-trial models — not as a claim about effects for any individual using this product.

Actin-Binding and Cell Migration Research

The foundational actin-sequestration finding (Safer et al., 1991, PMID 1999398) established Tβ4 as a major regulator of the actin monomer pool in cells. Building on this, in vitro research has examined how modulation of Tβ4 availability affects migration velocity and directionality of endothelial cells, fibroblasts, and keratinocytes in scratch-wound and transwell migration assays — cell types relevant to wound biology.

Tissue Repair and Angiogenesis Research (Animal Models)

Thymosin Beta-4 has been studied in wound-healing contexts across multiple animal-model systems, with investigators examining re-epithelialization rates, angiogenesis, collagen deposition, and inflammatory-cell recruitment in controlled experimental dermal, corneal, and cardiac wound models. These are preclinical findings in controlled animal research; they do not establish efficacy in humans and should not be interpreted as clinical evidence.

Inflammatory and Vascular Biology Research

Beyond migration and repair models, Tβ4 has been investigated for proposed anti-inflammatory properties in cell-culture and animal-model contexts, along with its proposed interaction with integrin-linked kinase (ILK) signaling connecting cytoskeletal dynamics to cell survival and growth-factor response pathways.

What the Human Evidence Shows

Researchers evaluating TB-500/Thymosin Beta-4 should know that controlled human clinical research does exist on this protein — but it was conducted with a pharmaceutical developer’s proprietary formulation, not with vendor-supplied research-grade TB-500. RegeneRx Biopharmaceuticals advanced a Thymosin Beta-4-based drug candidate into clinical study for chronic dermal wounds. A published European multicenter, double-blind, placebo-controlled, dose-escalation trial enrolled 73 patients with venous stasis ulcers across sites in Italy and Poland, and reported that a specific tested concentration was associated with a higher rate of complete wound closure within three months versus placebo, with a safety profile described as comparable to placebo (Int Wound J. 2011 Jun;8(3):230-6; PMID 20536470).

That trial is important context, but it does not establish safety or efficacy for the research-grade TB-500 sold on this page. It used a distinct, pharmaceutical-grade formulation developed and controlled by RegeneRx under its own clinical-development program — not a research-use-only compound sourced from a peptide vendor. Thymosin Beta-4 and TB-500 research compounds are not FDA-approved drugs for any indication, have not completed the clinical-trial pathway required for approval as a marketed product, and are not evaluated by the FDA for safety or efficacy in humans or animals.

This distinction matters for how findings from this page should be characterized. A researcher citing the RegeneRx trial in a grant application or protocol design should describe it accurately as evidence about a specific pharmaceutical-development candidate, not as safety or efficacy data for the research peptide supplied here. As more controlled human research is published, if any, this page will be updated to reflect it.

TB-500 is frequently studied alongside, or in fixed-ratio combination with, other tissue-repair and regenerative research peptides. First Class Science supplies several related preparations for researchers running comparative studies:

BPC-157 – 10mg is a separately-studied gastric pentadecapeptide also researched in tissue-repair contexts through a distinct proposed mechanism, and is commonly ordered alongside TB-500 by labs running comparative or combined tissue-repair protocols; a pre-blended BPC-157/TB-500 Blend Capsules preparation is also available.

TB-500 Capsules – 500mcg supplies the same research protein in an encapsulated format for laboratories that prefer not to reconstitute a lyophilized vial.

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.

Common Research Study Designs

Published studies referenced throughout this page typically fall into one of three designs: in vitro cell-migration and actin-binding assays isolating the cytoskeletal mechanism from other cellular activity; controlled animal-model wound and injury studies measuring closure rate, angiogenesis, and inflammatory markers; and, in the case discussed above, a controlled multicenter human trial of a distinct pharmaceutical-development candidate. Understanding which design underlies a given finding is important context for interpreting the strength of any individual claim in the literature.

Frequently Asked Questions

What is the relationship between TB-500 and Thymosin Beta-4?
TB-500 is the common research-community name for synthetic material corresponding to Thymosin Beta-4 (Tβ4), a naturally occurring 43-amino-acid protein. Published peer-reviewed literature on this biology is indexed under “Thymosin Beta-4,” not the vendor name “TB-500.”

What is the purity of this TB-500 research peptide?
Every batch is independently verified via third-party HPLC and mass-spectrometry testing, with a Certificate of Analysis published for each lot.

How should TB-500 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 TB-500 approved for human or animal use?
No. TB-500/Thymosin Beta-4 is not an FDA-approved drug for any indication and has not completed the clinical-trial pathway required for approval as a marketed product. It is sold exclusively for in vitro and laboratory research use.

Has Thymosin Beta-4 been tested in humans at all?
Yes, in a distinct pharmaceutical-development context: a controlled European Phase 2 trial examined a proprietary Thymosin Beta-4 formulation for venous stasis ulcers (PMID 20536470). That trial used a different, pharmaceutical-grade formulation than the research-use-only TB-500 sold here, and does not establish safety or efficacy for this product.

What does the Certificate of Analysis show?
The Certificate of Analysis published for each batch shows the HPLC purity result, mass-spectrometry molecular-weight confirmation, lot number, and test date, allowing researchers to independently verify the identity and purity of the specific batch they receive.

Can TB-500 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.

Shipping, Handling & Compliance

This TB-500 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 controlled clinical-trial 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.