Stored at -80°C for 1 year. It is stable at -20°C for 3 months after opening. It is recommended to freeze aliquots at -80°C for extended storage. Avoid repeated freeze-thaw cycles.
Biological Activity: Measured in a cell proliferation assay using A427 cells. The ED50 for this effect is 1.04 ng/mL, corresponding to a specific activity is 9.615×105 units/mg.