Observation of Desorption and Direct Electron Transfer Reaction of Cytochrome on Bare ITO Electrode with Electrochemical Slab Optical Waveguide Spectroscopy.

Cyclic voltammograms (CVs) of cytochrome (cytc) on the bare ITO were measured with every 10 times of the continuous the solution exchange (SE) processes at the same time of slab optical waveguide (SOWG) spectral observation, and it was proved that direct electron transfer (DET) reaction functionality of cytc adsorbed on the bare ITO electrode was kept after 100 times SE processes. The existence of three kinds of cytc molecules which were weakly adsorbed, strongly adsorbed and immobilized on the bare ITO electrode below a monolayer coverage was indicated from the change in the Soret band absorbance at 408 nm due to the desorption reaction of cytc with observation by electrochemically controlled SOWG spectroscopy. As the actual procedure, 100 times of the SE process in the SOWG cell by hands induced the gradual decrease of the absorbance due to cytc desorption, and with every 10 times of the SE process SOWG absorption spectra were obtained.

In situ Observation of Direct Electron Transfer Reaction of Cytochrome c Immobilized on ITO Electrode Modified with 11-{2-[2-(2-Methoxyethoxy)ethoxy]ethoxy}undecylphosphonic Acid Self-assembled Monolayer Film by Electrochemical Slab Optical Waveguide Spectroscopy.

To immobilize cytochrome c (cyt.c) on an ITO electrode while keeping its direct electron transfer (DET) functionality, the ITO electrode surface was modified with 11-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}undecylphosphonic acid (CHO (CHCHO)CHPO(OH), M-EG-UPA) self-assembled monolayer (SAM) film. After a 100-times washing process to exchange a phosphate buffer saline solution surrounding cyt.

Electrochemical control of the elution property of Prussian blue nanoparticle thin films: mechanism and applications.

We found a method for controlling the elution property of a thin film of water-dispersible Prussian blue (w-PB) nanoparticles using a simple electrochemical treatment. The thin film of the w-PB nanoparticles fabricated by the spin-coating method was unstable in water and eluted easily. However, after electrochemical reduction and oxidation, the film did not elute in water.