Duplex DNase can be heat inactivated by adding DTT or other reducing agent (1 mM final concentration) to a Duplex DNase reaction and incubating at 75°C for 10 minutes. If the sample contains RNA, we recommend adding EDTA (10 mM final concentration), along with DTT (1 mM final concentration) prior to heat inactivation as temperatures >65°C in the presence of divalent metals such as Mg²⁺ may degrade RNA.