A highly selective and sensitive two-photon chemosensor for silver ion derived from 3,9-dithia-6-azaundecane

A two-photon sensor for the silver ion derived from 3,9-dithia-6-azaundecane as the receptor is reported. The sensor exhibits high sensitivity to and selectivity for silver ion, and emits strong two-photon fluorescence when excited by 810 nm laser photons. Moreover, the binding constants measured by the one- and two-photon fluorescence are similar. This result may be useful for the design of efficient two-photon fluorescence probes for biological substrates.