Cubic phases in biosensing systems.

Incorporation of membrane proteins with retained activity in artificial membranes for use in membrane-based sensors has attracted scientists for decades. This review briefly summarises general concepts on relevant cubic phases with and without incorporated proteins and provides some insight into the development of biosensors where bicontinuous cubic phases are used for incorporation of an enzyme. Some new data on impedance characterisation of a supported cubic phase are also shown. An efficient membrane-based electrochemical biosensor requires that the analyte has free access to the immobilised membrane protein and that regeneration of the catalysing enzyme is fast. Long-term stability of the system is also necessary for the biosensor to find applications outside the research laboratory. These basic concepts are discussed in the review along with presentation of those biosensing systems based on cubic phases that are reported in the literature.