A highly sensitive and selective bis(salamo)-type fluorescent chemosensor for identification of Cu and the continuous recognition of S, Arginine and Lysine.

A novel bis(salamo)-type chemosensor HL was synthesized and characterized. It was found that the sensor molecule can selectively recognize Cu, and its L-Cu is highly sensitive to the detection of S anion, Arginine and Lysine when dissolved in ethanol solvent. The sensor HL can be used to identify a relay sensor for Cu, while the L-Cu recognizes S anion, Arginine and Lysine with high selectivity and sensitivity over an acceptable physiological pH range. The detection line of the sensor molecule HL is 1.02 × 10 M, and its binding constant to Cu is 1.54 × 10 M. The detection line of L-Cu as a sensor is calculated as 5.57 × 10 M, and its binding constants with S anion, Arginine and Lysine are 2.80 × 10 M, 5.32 × 10 M and 5.94 × 10 M, respectively. The crystal structure of the Cu(II) complex [Cu(L)(CHOH)]·2NO with the sensor molecule HL has been determined by single crystal X-ray crystallography.