Description
TB-500 Refill 10mg — Research-Grade Thymosin Beta-4 Actin-Binding Fragment Refill Cartridge for the Core Research Peptide Pen v3
The TB-500 Refill 10mg is a pre-filled lyophilised refill cartridge containing research-grade TB-500, a synthetic analogue of the naturally occurring peptide Thymosin Beta-4 (Tβ4). This refill format fits the Core Research Reusable Metal Peptide Pen v3 and is supplied for laboratory dispensing workflows that have adopted the pen system; it is not an administration device.
Each refill cartridge contains 10mg of lyophilised TB-500 acetate salt, verified by RP-HPLC to a minimum purity of ≥99.0%, with molecular identity confirmed by ESI-MS. Endotoxin content is certified at <1.0 EU/mg by kinetic turbidimetric LAL assay, and residual moisture is verified at <5.0% by Karl Fischer titration. A batch-specific Certificate of Analysis is included with every order.
Thymosin Beta-4 is the most abundant member of the beta-thymosin family of actin-sequestering peptides, present at concentrations of 0.5–1.0 mg/ml in most mammalian cells. Tβ4 binds G-actin (monomeric actin) with high affinity (Kd ~0.7 μM) through its LKKTET actin-binding motif, regulating the pool of unpolymerised actin available for cytoskeletal dynamics.
Compound Identity & Molecular Data
| Parameter | Value |
|---|---|
| Compound Name | TB-500 (Thymosin Beta-4 actin-binding fragment, LKKTET motif) |
| Sequence | Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln-Glu-Lys-Asn-Pro-Leu-Pro-Ser-Lys-Glu-Thr-OH |
| Residue Count | 17 amino acids; N-terminal acetylation |
| Molecular Weight | 2,025.33 Da (free base, monoisotopic) |
| CAS Number | 77591-33-4 (Thymosin Beta-4 fragment) |
| Salt Form | Acetate salt (lyophilised) |
| Primary Targets | G-actin (LKKTET motif), ILK/Akt, VEGF/HGF upregulation, NF-κB modulation |
| Research Classification | Actin-sequestering peptide; tissue repair; anti-inflammatory; angiogenic |
Analytical Release Testing — Refill Cartridge Specification
| Test | Method | Specification | Notes |
|---|---|---|---|
| Purity | RP-HPLC (C18, UV 220 nm) | ≥99.0% | Acetonitrile/water gradient; TFA modifier |
| Identity | ESI-MS | Confirmed ±0.1 Da | Expected [M+H]⁺: 2,026.34; [M+2H]²⁺: 1,013.68 |
| Endotoxin | Kinetic turbidimetric LAL | <1.0 EU/mg | USP <85> compliant method |
| Residual Moisture | Karl Fischer titration | <5.0% | Coulometric KF; lyophilisation quality indicator |
| Quantity per Cartridge | Gravimetric | 10 mg ± 5% | Lyophilised acetate salt; net peptide content |
| Compatible Device | — | Core Research Peptide Pen v3 | Use with 4mm 31G pen needles |
Reconstitution & Handling Guidance
TB-500 Refill cartridges are supplied in lyophilised form and must be reconstituted before use. For use with the Core Research Peptide Pen v3, reconstitute the cartridge with bacteriostatic water (0.9% benzyl alcohol in sterile water for injection) to the desired concentration. A typical reconstitution for research use is 2ml bacteriostatic water to yield a 5mg/ml solution. Allow the lyophilised cake to dissolve completely by gentle swirling — do not vortex. The reconstituted solution should be clear and colourless; discard if particulate matter or discolouration is observed.
TB-500 is soluble in aqueous buffers at concentrations up to 10mg/ml under standard conditions. Working solutions should be prepared fresh from frozen aliquots where possible to maintain peptide integrity.
Storage & Stability
| Condition | Temperature | Duration | Notes |
|---|---|---|---|
| Lyophilised cartridge (long-term) | −20°C | ≥24 months | Desiccated; protect from light and moisture |
| Lyophilised cartridge (short-term) | 2–8°C | Up to 4 weeks | Desiccated; suitable for active research use |
| Reconstituted in bacteriostatic water | 2–8°C | Up to 28 days | Benzyl alcohol preservative extends stability |
| Reconstituted aliquots (extended) | −80°C | Up to 12 months | Single-use aliquots; avoid repeated freeze-thaw cycles |
Frequently Asked Questions
What is the difference between TB-500 and full-length Thymosin Beta-4?
TB-500 is a 17-amino-acid synthetic fragment corresponding to the actin-binding domain (LKKTET motif) of full-length Thymosin Beta-4 (43 amino acids). Researchers requiring the full-length Tβ4 sequence should specify this when enquiring.
Can TB-500 Refill be used in combination with BPC-157 Refill in the same pen?
The pen system holds one cartridge at a time. Where a study calls for both BPC-157 and TB-500 in one preparation, the BPC-157 / TB-500 Blend Refill supplies the two peptides co-lyophilised in a single pre-measured cartridge; otherwise each refill is dispensed from its own pen.
Is a Certificate of Analysis provided with each refill?
Yes. A batch-specific Certificate of Analysis documenting RP-HPLC purity, ESI-MS identity, LAL endotoxin result, and Karl Fischer moisture content is included with every TB-500 Refill 10mg order.
Related Research Guides
Standard Format
TB-500 10mg — Full Vial
Complementary Refill
BPC-157 Refill 10mg
Blend Format
BPC-157 / TB-500 Blend 10mg
Compatible Device
Reusable Metal Peptide Pen v3
Reconstitution
Bacteriostatic Water 10ml
Category
All Refill Cartridges
Research context
The published literature on this material is summarised in the laboratory guides linked below. This record describes the material as supplied: identity, format, analytics, storage and documentation. It does not describe effects, and none should be inferred from the catalogue category.
For Research Use Only — Not for Human or Veterinary Use
TB-500 Refill 10mg is supplied exclusively for in vitro and pre-clinical in vivo research use with the Core Research Reusable Metal Peptide Pen v3. This product has not been evaluated by the MHRA, FDA, or any other regulatory authority for safety or efficacy in humans or animals. Purchase confirms the buyer is a qualified researcher operating within applicable institutional and legal frameworks.
