A crown-ether-type colorimetric chemosensor EDDAJ (9,9′-((1E,11E)-5,8-dioxa-2,11-diazadodeca-1,11-diene-1,12-diyl)bis(2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-8-ol) was synthesized. EDDAJ could detect Fe^3+/2+ by a color variation from colorless to dark green in aqueous media. Detection limit of iron ion was 0.43 μM. Complexation ratio of EDDAJ to Fe³⁺ was determined to be 1:1 with the results of Job plot and ESI-mass. Based on Job plot, EPR, and ESI-mass experiments, the probing mechanism of EDDAJ to Fe^3+/2+ was demonstrated.

中文翻译：

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用比色法测定 Fe3+/2+ 的冠醚型化学传感器

冠醚型比色化学传感器EDDAJ (9,9'-((1E,11E)-5,8-dioxa-2,11-diazadodeca-1,11-diene-1,12-diyl)bis(2,合成了 3,6,7-四氢-1H,5H-吡啶并[3,2,1- ij ]quinolin-8-ol) 。EDDAJ可以通过颜色从无色到深绿色的变化来检测 Fe ^3+/2+水介质。铁离子的检测限为0.43 μM。根据Job plot和ESI-mass的结果确定EDDAJ与Fe ^3+的络合比为1:1。基于Job plot、EPR和ESI-mass实验,证明了EDDAJ对 Fe ^3+/2+的探测机制。