Four rhodamine 6G-based chemosensors (H 3 L1-H 3 L4) are designed for selective detection of Al3+ ion. They are characterized using various spectroscopic techniques and X-ray crystallography. All absorption and emission spectral studies have been performed in 10 mM N-(2-hydroxyethyl)piperazine-N'-ethanesulfonic acid (HEPES) buffer solution at pH 7.4 in H2O/MeOH (9:1, v/v) at 25 °C. In absorption spectra, chemosensors exhibit an intense band around 530 nm in the presence of Al3+ ion. Chemosensors (H 3 L1-H 3 L4) are nonfluorescent when excited around 490 nm. The presence of Al3+ ion enhances the emission intensity (555 nm) many times. The formation of complexes 1-4 is established with the aid of different spectroscopic techniques. The limit of detection value obtained in the nanomolar range confirms the high sensitivity of the probes toward Al3+ ion. It has been observed that the presence of aliphatic spacers in the diamine part and different halogen substituents in the salicylaldehyde part strongly influences the selectivity of the chemosensors toward Al3+ ion. The propensity of the chemosensors to identify intracellular Al3+ ions in triple-negative human breast cancer cell line MDA-MB-468 by fluorescence imaging is also examined in this study.

中文翻译：

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基于罗丹明6G的Al3 +离子检测荧光化学传感器的开发：环应变和取代基在增强其传感性能方面的作用。

四个基于罗丹明6G的化学传感器（H 3 L1-H 3 L4）设计用于选择性检测Al3 +离子。使用各种光谱技术和X射线晶体学对其进行表征。所有吸收和发射光谱研究均在25 m的H2O / MeOH（9：1，v / v）中于pH 7.4的10 mM N-（2-羟乙基）哌嗪-N'-乙磺酸（HEPES）缓冲溶液中进行C。在吸收光谱中，在Al3 +离子存在下，化学传感器在530 nm附近显示出一个强带。化学传感器（H 3 L1-H 3 L4）在490 nm附近激发时不发荧光。Al 3+离子的存在可将发射强度（555 nm）提高很多倍。配合物1-4的形成借助不同的光谱技术来确定。在纳摩尔范围内获得的检测值的极限证实了探针对Al 3+离子的高灵敏度。已经发现，在二胺部分中存在脂族间隔基并且在水杨醛部分中存在不同的卤素取代基强烈地影响化学传感器对Al 3+离子的选择性。本研究还研究了化学传感器通过荧光成像鉴定三阴性人类乳腺癌细胞MDA-MB-468中细胞内Al3 +离子的倾向。