A novel and simple cyanide chemosensor 2-（naphthalen-1-ylmethylene）malononitrile（L） was designed and synthesized via a green chemistry method in water without using any catalyst.The chemosensor showed an excellent sensitivity and selectivity for CN in aqueous solution.The detection limit could be as low as 1.6×10~7 moI/L（0.16μmol/L）,which is far lower than the WHO guideline of 1.9μmol/L cyanide for drink water.
By applying an indirect strategy, a new copper （II） complex of a thiosemicarbazone L has been successfully developed as a colorimetric cbemosensor for the sensitive detection of mercury （II） ions. In the presence of copper （II） ions, the colorless so- lution of L became yellow; however, upon the addition of traces of mercury （II） ions, the yellow color faded to colorless im- mediately. Other ions, including Fe3＋, Ag＋, Ca2＋, Zn2＋, Pb2＋, Cd2＋, Ni2＋, Co2＋, Cr3＋ and Mg2＋ had a negligible influence on the probe behavior. The detection limits were 5.0×10^-6 M and 3.0×10^-7 M of Hg2＋ using the visual color changes and UV-vis changes respectively. Test strips based on Cu-L were fabricated, which could act as a convenient and efficient Hg2＋ test kits.
