Amperometric nitric oxide microsensor using two-dimensional cross-linked Langmuir-Blodgett films of polysiloxane copolymer

An amperometric nitric oxide (NO)-sensing microelectrode was constructed using two-dimensional (2D) cross-linked Langmuir-Blodgett (LB) films of siloxane copolymer as permselective membranes in order to block other electroactive interfering species. The 2D cross-linked siloxane LB films deposited on platinum micro-disc electrodes (10 μm in diameter) were highly effective in the elimination of the interfering responses (e.g., the ratio of current response for dopamine on the modified electrode to that on the bare electrode, less than 10−4). Furthermore, high sensitivity to NO (detection limit, 40 nM) was also remained with modified LB films consisting of monolayers.