A multifunctional tripodal fluorescent probe: "off-on" detection of sodium as well as two-input AND molecular logic behavior.

A simple tripodal sensor (3) with multifunctional capability has been synthesized in three steps. The sensor, a naphthalene-functionalized Schiff base, displays selectivity for sodium over other important physiological and environmentally important cations through changes in the emission spectra at lambda(max) 355 nm when excited at 270 nm. Interestingly, the combined addition of both sodium and potassium produced a new band at lambda(max) 445 nm, while the addition of sodium or potassium alone produced negligible changes at this wavelength. Therefore, the conditions of a two-input AND logic operator were also satisfied.