Electrochemical fingerprint of cytochrome c on a polymer/MWCNT nanocomposite electrode.

The electroactivity of cytochrome c on screen-printed graphite electrodes modified with stable dispersions of multi-walled carbon nanotubes in aqueous solution of amphiphilic poly(n-butyl acrylate) 100 - block -poly(acrylic acid) 140 diblock copolymers was estimated. Using a broad potential window, the reduction and oxidation of heme iron at a near-zero potential, the electrooxidation of Tyr and Trp at +0.6 V and the electrooxidation of heme at +0.8 V were detected in a wide concentration range of 1–100 μm with a limit of detection of 1–2 μm. Such a multipoint detection can be used as an electrochemical fingerprint of cytochrome c for its electrochemical recognition and quantification in complex (bio)chemical analytes. [ABSTRACT FROM AUTHOR]