Kumari Namita, Jha Satadru, Bhattacharya Santanu
Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012 1 (India), Fax: (+91) 080-2360-0529.
Chem Asian J. 2014 Mar;9(3):830-7. doi: 10.1002/asia.201301390. Epub 2014 Jan 21.
A new molecular probe based on an oxidized bis-indolyl skeleton has been developed for rapid and sensitive visual detection of cyanide ions in water and also for the detection of endogenously bound cyanide. The probe allows the "naked-eye" detection of cyanide ions in water with a visual color change from red to yellow (Δλmax =80 nm) with the immediate addition of the probe. It shows high selectivity towards the cyanide ion without any interference from other anions. The detection of cyanide by the probe is ratiometric, thus making the detection quantitative. A Michael-type addition reaction of the probe with the cyanide ion takes place during this chemodosimetric process. In water, the detection limit was found to be at the parts per million level, which improved drastically when a neutral micellar medium was employed, and it showed a parts-per-billion-level detection, which is even 25-fold lower than the permitted limits of cyanide in water. The probe could also efficiently detect the endogenously bound cyanide in cassava (a staple food) with a clear visual color change without requiring any sample pretreatment and/or any special reaction conditions such as pH or temperature. Thus the probe could serve as a practical naked-eye probe for "in-field" experiments without requiring any sophisticated instruments.
一种基于氧化双吲哚骨架的新型分子探针已被开发出来，用于快速、灵敏地可视化检测水中的氰离子，以及检测内源性结合的氰化物。该探针加入后能使水中的氰离子发生从红色到黄色的明显颜色变化（Δλmax = 80 nm），实现“裸眼”检测。它对氰离子具有高选择性，不受其他阴离子的干扰。该探针检测氰化物是比率型的，因此检测是定量的。在此化学计量检测过程中，探针与氰离子发生迈克尔型加成反应。在水中，检测限为百万分之一级别，当使用中性胶束介质时，检测限大幅提高，达到十亿分之一级别，甚至比水中氰化物的允许限量低25倍。该探针还能在无需任何样品预处理和/或特殊反应条件（如pH或温度）的情况下，通过明显的颜色变化高效检测木薯（一种主食）中内源性结合的氰化物。因此，该探针可作为一种实用的裸眼探针用于“现场”实验，无需任何复杂仪器。
