Colorimetric indicators for specific recognition of Cu2+ and Hg2+ in physiological media: Effect of variations of signaling unit on optical response
Colorimetric indicators for specific recognition of Cu2+ and Hg2+ in physiological media: Effect of variations of signaling unit on optical response
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DOI：
10.1016/j.ica.2018.09.074
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发表时间：
2019-03-01
影响因子：
2.8
通讯作者：
Bhattacharya, Santanu
中科院分区：
文献类型：
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作者：
Dey, Nilanjan;Kumari, Namita;Bhattacharya, Santanu
易于合成的探针设计使用双吡啶甲基部分作为受体单元，具有两个不同的信号传导部分，蒽醌和双吲哚基。这两种化合物在~ 100%水性介质中显示出对Cu 2+和Hg 2+的“裸眼”感测。不仅选择性，化合物还显示出对目标金属离子的高灵敏度，如其足够低的检测限所证明的。本系统可以从可见的颜色变化中检测低至0.06ppm的Cu 2+和高达0.03ppm的Hg 2+。传感器被发现同样有效地检测金属离子，即使在蛋白质结合状态。已经观察和研究了信号单元对具有相同结合单元的探针的传感性质的影响。机理研究表明，信号单元的变化影响pK（a）的bispicolyl氮，随后控制的化学计量的探针金属离子络合物，以及它们的发光性能。此外，在加标水样中的Cu 2 +/Hg 2+的估计中，获得了高特异性和良好的准确度，回收率为98.0%至104.0%。开发了低成本、可重复使用的纸条，用于现场检测金属离子，不需要光学仪器的帮助。
Easy to synthesize probes are designed using bispicolyl moiety as the receptor unit with two different signaling moieties, anthraquinone and bisindolyl. Both the compounds show 'naked-eye' sensing of Cu2+ and Hg2+ in -100% aqueous medium. Not only selectivity, the compounds also show high sensitivity towards the target metal ions, as evident by their sufficiently low detection limits. The present system can detect Cu2+ as low as 0.06 ppm and Hg2+ up to 0.03 ppm from visible color change. The sensors are found equally effective in the detection of metal ions even in the protein-bound state. The impact of the signaling unit on the sensing properties of probes having same binding units has been observed and investigated. Mechanistic investigations revealed that variations in signaling unit influence the pK(a) of the bispicolyl nitrogens, which subsequently controls the stoichiometry of the probe-metal ion complexes as well as their luminescence property. Additionally, high specificity and good accuracy with recovery values ranging from 98.0 to 104.0% were obtained during Cu2+/Hg2+ estimation in spiked water samples. Low cost, reusable paper strips were developed for on-site detection of the metal ions which does not require the assistance of an optical instrument.