A membraneassociated enzyme, cytochrome c oxidase, has been put in lipid bilayer membranes attached to gold electrode surfaces. Goldhhiol self-assembly chemistry and deoxycholate dialysis procedures have been used to insert cytochrome c oxidase into a lipid bilayer on gold surfaces with a controlled orientation. Voltammetric and spectroelectrochemical results indicate that direct electron-transfer communication between the gold electrode surface and cytochrome c oxidase has been achieved. Moreover, immobilized cytochrome c oxidase can both reduce and oxidize solution-resident cytochrome c by appropriately controlling the applied electrode potential.
The second harmonic frequency is monitored using a conventional lock-in amplifier in a continuous scan cyclic voltammetric experiment. The background charging current is predominantly composed of odd harmonic frequencies, while the analyte Faradaic signal is composed of both odd and even harmonic frequencies. By 'locking-in' on the second harmonic frequency one can isolate the Faradaic current from the charging current in the frequency domain. Model compounds (hexaammineruthenium(iii) chloride, ferrocene) at carbon and gold microelectrodes a s well as carbohydrates at copper microelectrodes were examined in flow injection analysis experiments. Limits of detection an order of magnitude lower than D C amperometry were observed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.