Electron Transfer between Electrodes and Heme Proteins in Protein−DNA Films

Electrodes with immobilized DNA can be used as DNA sensors, and for many other applications. Herein we report stable films of calf thymus (CT) double stranded (ds) DNA and proteins on pyrolytic graphite (PG) electrodes in which direct electron transfer involving heme protein Fe(III)/Fe(II) couples is achieved. DNA films on PG also extracted heme proteins from solution. Myoglobin diffused into pure DNA films much faster than hemoglobin.