Selective picomolar detection of mercury(II) using optical sensors.

The rational design of a mercury(II) ligand consisting in a 1-(4'-oxyphenyl)-4(1'-pyrenyl)-2,3-diaza-1,3-butadiene receptor unit, optimizes the sensitivity and reliability of a SPR sensor by the formation of a well packed SAM over the gold surface. SPR analysis allows detecting mercury(II) concentrations in aqueous systems in the picomolar range, meliorating on three orders of magnitude the EU mercury(II) detection limit in drinkable water.