Pyrrole-Based Schiff-Base Sensor for Copper Ions

摘要

A new,simple,and reversible Schiff base,(E)-N'-((1H-pyrrol-2-yl)methylene)isonicotinohydrazide(L),has been designed,synthesized,and characterized for its optical and elemental properties.The synthesized sensor,L is then successfully investigated for selective and sensitive detection of Cu~(+2)ions by the colorimetric and spectroscopic method in an aqueous organic solvent.The sensor L showed high selectivity toward Cu~(+2)ions over other possible interfering ions(Na~+,K~+,Ca~(+2),Mg~(+2),Co~(+2),Ni~(+2),Zn~(+2),Cd~(+2),Pb~(+2),Cr~(+3),Ag+,Al~(+3)and Mn~(+2))and in a wide pH range.The detection limit reaches up to 17.6 μM,which is lower than the WHO recommended guidelines for drinking water,while the limit of quantification was found to be 58 μM.The binding mode of complexation between Cu~(+2)and L was found to be 1: 1 using Job's plot.For practical usage,the designed sensor(L)is transferred onto paper strips and demonstrated for real sample analysis through naked eye color change.