ELECTROACTIVE DEPOSITS OF ANTHRAQUINONE-ATTACHED MICELLE-FORMING AND VESICLE-FORMING SURFACTANT ASSEMBLIES ON GLASSY-CARBON SURFACES

Three cationic surfactants with covalently attached anthraquinone moie ties at the headgroup region, 1-3, were synthesized. The single chain surfactant, 0-dihydro-9,10-dioxoanthracen-2-yl)methyl)ammonium bromide , 1, upon comicellization with cetyltrimethylammonium bromide (CTAB) i n water gave micellar aggregates with anthraquinone residues attached at the exposed aqueous interfaces. The two double chain amphiphiles, 0 -dihydr-9,-10-dioxoanthracen-2-yl)methyl)ammonium bromide, 2, and 0-di hydro-9,10-dioxoanthracen-2-yl)methyl)ammonium bromide, 3, however, on suspension with either dioctadecyldimethylammonium bromide (DODAB) or alone in aqueous media gave vesicular assemblies with anthraquinone r esidues attached both at the inner and at the outer aqueous vesicular surfaces. Holomicellar I or comicellar 1/CTAB deposited on to the glas sy carbon electrode surface during cyclic voltammometric studies. Abov e their critical temperatures for the gel to liquid-crystalline-like p hase transitions, the vesicular systems also formed electroactive laye rs on glassy carbon electrodes. In this paper, we present in detail va rious electrochemical aspects concerning these anthraquinone aggregate s and the role of introduction of electrochemically inert cosurfactant s in the formation of such electroactive deposits.