Electrochemical, Spectroscopic and Microscopic Characterisation of Novel Poly(3,4-ethylenedioxythiophene)/Gold Nanoparticles Composite Materials.

Composite materials consisting of poly(3,4-ethylenedioxithiophene) including Au nanoparticles encapsulatedby bulky anionic species have been electrogenerated and characterised through spectroscopic andmicroscopic techniques. The properties of electrodes modified by similar materials have been studiedwith respect to the oxidation of different benchmark electroactive species, such as negatively chargedascorbic and uric acids, and positively charged dopamine. The responses obtained evidence the dependenceof sensitivity and selectivity of the electrochemical responses on the presence and density of thenanoparticles and on the nature of the relevant encapsulating agent. In particular, the insertion of negativelycharged NPs activates a sort of electrostatic shield toward negatively charged molecules; however,also positively charged species result to be conditioned in accessing the redox active centres, locatedeither on the nanoparticle’s surface or on the conducting polymer’s molecules.