# FAQ: Can you tell me what inhibits SplintR Ligase?

SplintR Ligase is active between 4-37°C. Above this temp, the enzyme starts to denature. It is mostly inactivated after 10 minutes at 65°C. Additionally, monovalent cations such as NaCl and KCl inhibit the enzyme. These components should be kept below 50 mM in the reaction. We supply the enzyme in 300 mM NaCl to maintain robust activity over its shelf life at -20°C, but the enzyme needs to be diluted by addition to the reaction. This is easily achieved by choosing a 20-fold dilution in the reaction set-up (e.g. 1 ul of enzyme in a 20 ul reaction). As with most enzymes, the presence of ionic detergents and denaturants, such as SDS, urea, and Guanidine HCl should be avoided.