Prussian blue nanoparticles protected by the water-soluble pi-conjugated polymer PEDOT-S: synthesis and multiple-color pH-sensing with a redox reaction.

Prussian blue nanoparticles (PB NPs), stabilized for the first time by the pi-conjugated polymer poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-2yl-methoxy-1-butanesulfonic acid, potassium salt) (PEDOT-S), demonstrated a novel multiple-color pH-sensing function with a redox reaction based on the electronic interaction between the PB nano-core and the PEDOT-S shell.