A fluorescent sensor based on a diarylethene-rhodamine derivative for sequentially detecting Cu~(2+) and arginine and its application in keypad lock

摘要

A new diarylethene-rhodamine derivative (10) has been synthesized. It displayed colorimetric and fluorometric sensing abilities toward Cu~(2+) in CH_3CN-H_2O (4/1, v/v) solution. The fluorescence and absorbance detection limits for Cu~(2+) were calculated to be 0.31 μM and 0.28 μM, respectively. More importantly, the 10-Cu~(2+) complex showed highly selective and sensitive recognition toward arginine (Arg) with the detection limit as low as 2.2 μM. Experiments also showed that the resulting 10-Cu~(2+) complex could function as a reversible fluorescence photoswitch in the response to UV-vis light due to the fluorescence resonance energy transfer mechanism. Moreover, 10 could behave as a molecular "keypad lock" with different order of chemical inputs of Cu~(2+) and Fe~(3+).