LANGMUIR-BLODGETT-FILMS OF PHTHALOCYANINATO-POLYSILOXANE-POLYMERS AS A NOVEL TYPE OF CHEMFET-MEMBRANE

Abstract

The formation of Langmuir-Blodgett films (LB-films) by substituted phthalocyaninato-polysiloxane-polymers is a new principle in this field of research since this material lacks the amphiphilic nature which has been thought of being the basic requirement for successful LB film production. Multilayers of the polymere were built up and successfully transferred to Si/SiO, -substrates. They formed macroscopically well-ordered, thermally and chemically stable films. In an Electrolyte/Insulator/Silicon-configuration (EIS-system) they were tested for their usability as CHEMFET-membranes. A long-time stability of at least 3 months in contact with buffer solutions was observed. A pH-sensitivity of 40-50 mV/pH was found with a permanent but irregular baseline drift probably due to ionic migration in the membrane.