Thin-Film Modified Electrodes with Reconstituted Cellulose−PDDAC Films for the Accumulation and Detection of Triclosan

A strategy for the formation of thin reconstituted cellulose films (pure or modified)) with embedded receptors or embedded ion-selective components is reported. Cellulose nanofibril ribbons from sisal of typically 3−5 nm diameter and 250 nm length are reconstituted into thin films of typically 1.5−2.0 μm thickness (or into thicker free-standing films). Cellulose and cellulose nanocomposite films are obtained in a simple solvent evaporation process. Poly-(diallyldimethylammonium chloride) or PDDAC is readily embedded into the cellulose film and imparts anion permselectivity to allow binding and transport of hydrophobic anions. The number of binding sites is controlled by the amount of PDDAC present in the film. The electrochemical properties of the cellulose films are investigated first for the Fe(CN)63-/4- model redox system and then for the accumulation and detection of triclosan (2,4,4‘-trichloro-2‘-hydroxydiphenyl ether, a hydrophobic polychlorinated phenol). Pure nanocellulose thin films essentially b...