STRUCTURAL CHARACTERIZATION AND SURFACE MODIFICATION OF EVAPORATED THIN-FILMS OF IS(AMINOMETHYL)-2,2'5',2''5'',2'''-QUATERTHIOPHENE AND ITSDIHYDROCHLORIDE

Thin films of 5,5'''-bis(aminomethyl)-2,2':5',2 '':5 '',2'''-quaterthi ophene, (1) and its dihydrochloride (2), both of which possess active amino groups at both the molecular terminals, have been fabricated by direct evaporation deposition. IR and XPS analyses have revealed that these thin films are deposited without causing chemical degradation du ring the course of deposition. Of these, the thin film of 1 is charact erized by the molecular layered structure that can be noticed for the oligothiophene compounds widely, and in this structure the molecular l ong axis of 1 is nearly vertical to the substrate plane. On the other hand, the film of 2 turned out to be amorphous. The structure of 1 imm ediately means the presence of a densely packed array of the amino gro ups at the thin film surface. Making use of this structure, we tried s urface modification of the thin film of 1 with an aldehyde. The result ing film was analyzed by XPS spectroscopy, and as a consequence, we co nfirmed that the surface modification is successfully achieved. Furthe rmore, we attempted immobilization of glucose oxidase (GOD) onto the t hin film of 1 and examined its catalytic activity.