School of Chemistry and Environment, South China Normal University, Shipai, Guangzhou 510631, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2013 Dec;116:460-5. doi: 10.1016/j.saa.2013.07.069. Epub 2013 Aug 3.
In this study, we reported a new fluorescence sensor for chromium (III) ion, dansyl-L-glutamine (1). The sensor displayed a unique selective fluorescence "turn-on" response to Cr(3+) over other common metal ions in water. Notably, 1 still showed a ratiometric response to Cr(3+) in UV-vis absorption spectra. The binding mechanism of 1 to Cr(3+) was further clarified by using NMR and ESI-MS spectra. The experiment results indicated that the dual-responses of 1 to Cr(3+) should attribute to the coordination of deprotonated sulfonamide group with Cr(3+) and the protonation of the dimethylamino group due to the coordination of Cr(3+) for 1. In addition, two chloride ions also coordinated to the complex of sensor-chromium (III) ion, which further strengthened the conformation of 1-Cr(3+).
在这项研究中，我们报道了一种用于检测三价铬离子的新型荧光传感器，丹磺酰基-L-谷氨酰胺（1）。该传感器在水溶液中对 Cr(3+)具有独特的选择性荧光“开启”响应，可选择性识别 Cr(3+)。值得注意的是，1 在紫外可见吸收光谱中对 Cr(3+)仍表现出比率响应。通过使用 NMR 和 ESI-MS 光谱进一步阐明了 1 与 Cr(3+)的结合机制。实验结果表明，1 对 Cr(3+)的双重响应归因于去质子化磺酰胺基团与 Cr(3+)的配位和由于 Cr(3+)的配位导致二甲氨基的质子化。此外，两个氯离子也与传感器-三价铬离子的配合物配位，这进一步加强了 1-Cr(3+)的构象。
