TNF alpha (Tumor necrosis factor α), Human

Source:
Escherichia coli

Endotoxin Test:
<0.1 EU per 1 μg of the protein by the LAL method.

Activity:
Measure by its ability to induce cytotoxicity in L929 cells in the presence of actinomycin D. The ED₅₀ for this effect is < 0.1 ng/mL.
The specific activity of recombinant human TNF alpha is approximately ≧ 1 x 10⁷ IU/mg.

Purity:
>97% as determined by SDS-PAGE.

Form:
Lyophilized

Storage Buffer:
Lyophilized from a 0.2 μm filtered solution of PBS, pH 8.0.

Reconstitution:
It is recommended to reconstitute the lyophilized protein in sterile H₂O to a concentration not less than 200 μg/mL and incubate the stock solution for at least 20 min to ensure sufficient re-dissolved.

Stability & Storage:
This product is stable after storage at:
• -20°C for 12 months in lyophilized state from date of receipt.
• -20°C or -80°C for 1 month under sterile conditions after reconstitution.
Avoid repeated freeze/thaw cycles.