Using perylene-doped polymer nanotubes as fluorescence sensors.

Al(2)O(3) filters (200 nm) are used as templates to form polymer nanotubes containing an energy donor (perylene). The perylene is isolated from chemical interactions but can undergo electronic energy transfer to acceptor molecules in aqueous solutions passing through the membrane. This energy transfer is analyzed quantitatively in terms of both radiative and nonradiative (Forster transfer) mechanisms and provides a way for the chemically inert filter to sense the presence of analyte molecules in the filtrate.