The popular anaesthetic gas isoflurane is found to be electrochemically inert on a wide range of conventional electrode materials in both aqueous and nonaqueous solvents. However, the chemically modified electrode produced by depositing the novel electroactive polymer, poly(vinylfluoranthene), onto a platinum electrode is shown to mediate electron transfer to the anaesthetic thus bringing about its electro-reduction and so offers the promise of amperometric electrochemical sensors based on this electrode.