DSN was purified from Red King (Kamchatka) crab hepatopancreas using modified protocol from Shagin et al., 2002. DNAase activity was measured using modified Kunitz assay (Kunitz, 1950), where unit definition was defined as: the amount of DSN added to 50 μg/ml calf thymus DNA that causes an increase of 0.001 absorbance units per minute. Activity assay was performed at 25°C, in 50 mM Tris-HCl buffer, pH 7.15, containing 5 mM MgCl₂.

Shipping and Storage conditions:
All components of the kit can be shipped at ambient temperature. Upon arrival all components must be stored at -20°C.