For some helicases, it is possible to investigate RNA translocase activity on DNA substrates because the enzyme acts on both substrates. Potassium permanganate (KMnO4) footprinting is a method used to chemically probe the conformation of DNA as well as the binding of proteins. Combining footprinting methods with rapid mixing methods that utilize a chemical quench-flow instrument can enable tracking of the translocase with nucleotide resolution.