TB-500

What it is

Thymosin β4 is a 43-residue protein found in almost every cell. This product is the seven-residue stretch at positions 17–23, Ac-LKKTETQ, which is the protein's main actin-binding region. The name TB-500 is also used by some sellers for full-length thymosin β4; this product is the fragment.

What researchers study

• Thymosin β4 binds G-actin and controls actin polymerization. The 17–23 fragment is used to study that activity.
• Studied in cell-migration and wound models in cell culture and animals.

Specifications

How each lot is tested

Samples from every lot go to an independent, ISO/IEC 17025 accredited lab. Its report covers three tests:

• Purity by reversed-phase HPLC: the main peak's share of the total peak area.
• Identity by mass spectrometry: the observed mass should match the expected 889.0 g/mol.
• Endotoxin, measured for every lot.

The lot number on your vial is the number on its report. How to check a certificate of analysis walks through what to look for.

The amount on the label is the weight of the powder. Besides the peptide it includes counter-ions and some water; Purity vs. peptide content explains the difference.

Storage and handling

Store unopened vials at 2 to 8 °C, away from light, as printed on the label. Let a cold vial reach room temperature before you open it, so moisture doesn't condense on the powder. More bench habits are in Handling.