Anthraquinone–ferrocene film electrodes: Utility in pH and oxygen sensing

The synthesis and electrochemical characterization of anthraquinone–ferrocene is discussed. The ability of such molecules to form the basis of a pH sensor is demonstrated. These sensing capabilities are achieved through monitoring the variation in peak potential of the redox and pH active anthraquinone moiety with respect to the redox active but pH inactive ferrocene moiety. Such single molecule pH sensors should provide easy manufacturing and longterm stability when incorporated into sensor designs. Furthermore the anthraquinone moiety was also found to respond to the presence of oxygen which may allow its use in oxygen sensing processes with no detrimental affect to its pH sensing capabilities.