作者:Thorfinnur Gunnlaugsson、T. Clive Lee、Raman Parkesh
DOI:10.1016/j.tet.2004.08.047
日期:2004.11
to typical monomeric anthracene emission, due to suppression of PET, that is, the anthracene emission was ‘switched on’. Nevertheless, in the presence of Cd(II) a broad emission centred at 500 nm was observed, similar to that seen for 1. These ion induced long wavelength emission bands were assigned to the formation of charge-transfer complexes (exciplexes) between the anthracene moieties and the ion-receptor
描述了两种新型化学传感器1和2的设计,合成和光物理评估,用于选择性检测pH 7.4的水中的Cd(II)。两者均基于使用芳族亚氨基二乙酸酯受体,该受体通过共价甲基间隔基与蒽荧光团连接。这些是高度水溶性的传感器,由于受体对蒽激发态的光诱导电子转移(PET)猝灭,因此在pH值为3-11时荧光会“关闭”。然而,受体质子化后,发射被“接通”。根据这些变化,确定1和2的pK a s为1.8和2.5分别。两者都显示出对Cd(II)优于竞争性离子(如II组和Zn(II),Cu(II),Co(II))的良好选择性。对于具有单个受体的1,对于游离传感器,在pH 7.4(HEPES缓冲液,135 mM NaCl)下仅观察到弱的蒽蒽排放。Zn(II)滴定后,出现了宽红移发射,中心在468 nm。在Cd(II)存在下,也观察到了类似的红移发射,但是这次集中在506 nm处。与这些结果相反,由于抑制了PET,在Zn(