Lyophilized solid. Peptide-fluoromethyl ketone inhibitor of Caspases-13. The CH2F (fluoromethyl ketone) inhibitor has several advantages over other types of derivatives: Penetrates cell membranes, Not toxic to cells, Irreversible inhibition.
Dissolve the Caspase-13 Inhibitor in DMSO before use. It is important that dry, good quality DMSO be used.

For use on intact cells:
1. Prepare desired concentrated stock solutions as follows:
3 mg Z-LEED-FMK
in 21μl DMSO = 20 mM
in 43μl DMSO = 10 mM
in 86μl DMSO = 5 mM, etc.

2. Add 2 μl of above stock solution to 1 ml culture medium containing cells such that the fμl DMSO concentration is 0.2%. Levels of DMSO above this may cause some cellular toxicity, thus masking the effect of the Caspase-13 protease inhibitor. Adding 2 μl of a 10 mM stock solution to 1 ml of culture medium gives a final Z-LEED-FMK concentration of 20 μM. Typical final concentrations are 5 - 20 μM.

For extended use in vivo and in vitro:
For experiments extending 12 to 48 hours, fresh inhibitor may have to be added (injected) due to inactivation of the inhibitor by endogenous cysteine proteases.