Dynamic redox recycling of cytochrome c

Abstract Interdigitated array (IDA) electrodes were used to study the electrochemical behaviour of the soluble redox protein cytochrome c . The IDA electrodes consisted of 70 pairs of thin-film gold microbands, each of it with 2.9 μm band width and 1.1 μm interelectrode spacing. The surface of the gold electrodes was modified by 4,4′-dithiodipyridine and N-acetyl cystein in order to promote the electron transfer between cytochrome c and the electrodes. The close spacing in the interdigital arrangement allows generation/collection experiments with the oxidized and reduced form of cytochrome c . Applying this technique the diffusion coefficient of cytochrome c in buffered aqueous solution was determined to be 8.37 × 10 −7 cm 2 s −1 .