Layer-by-layer assembly of Prussian blue and carbon nanotube composites with poly(diallyldimethylammonium chloride) for the sensitive detection of hydrogen peroxide.

Prussian blue (PB) was deposited on multi-walled carbon nanotubes (MWCNT) in an aqueous solution. Multi-layer composites of the MWCNT-PB hybride material were obtained by layer-by-layer assembly with poly(diallyldimethylammonium chloride) (PDDA). The resulting {PDDA/MWCNT-PB}(n) multilayer films immoblized on glassy carbon electrodes showed sensitive detection for the reduction of hydrogen peroxide. A sensor based on the {PDDA/MWCNT-PB}(n) multilayer structure was fabricated and showed excellent sensitivity to the electrochemical reduction of hydrogen peroxide. Its response sensitivity increased with the number of the multilayers. A high response sensitivity of 0.83 mA M(-1) cm(-2) was obtained for a seven-layer sensor. This redox active multilayer structure offers potential applications in the development of high performance biosensors and biofuel cells.