pNA (4-nitroaniline)-derived caspase substrates are widely used for the colorimetric detection of various caspase activities. Cleavage of pNA peptides by caspases generates pNA that is monitored colorimetrically at ~405 nm. pNA has maximum absorption around 408 nm.
Caspase-1 substrate with Km = 23 µM and kcat = 1.5 M-1s-1
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