Chemical sensitivity of porphyrin nanotubes

Nanostructured molecular assembly provides, in many cases, peculiar proper-ties that are hot found in the individual constituents. Among three-dimensional arrangements the tubular structures are particularly appealing for chemical sensor applications at least for the expected surface increase. In this paper, the sensing properties of nanotubes self-assembled of oppositely charged porphyrins are investigated for the first time. Nanotube arrangement is shown to increase the sensitivity in both mass and optical sensors. The optical sensitivity, not found in individual porphyrins, appears as an intrinsic nanotube property.