An easy to make organic probe (hereafter called as R) possessing multiple ligating sites have been synthesized and characterized using spectral techniques. The probe exhibits selective and sensitive turn-on fluorescence response with Al(III) in aqueous dimethylformamide (DMF) (1:1 v/v) solution. Fluorescence titration experiment shows that the probe binds with Al(III) with a 1:1 stoichiometry and a binding constant of 6.6 × 104 M-1.The mode of coordination of R with Al(III) has been established suing 27Al and 1H NMR studies and the results suggest formation of an octahedral complex been them. The suggested point of attachment of R with Al(III) corroborates well with Density Functional Theory (DFT) optimized structure and Mulliken charges computed. Chelation-enhanced fluorescence (CHEF) is proposed as the mechanism of enhancement of fluorescence upon addition of Al(III) to R. The probe detects Al(III) in aqueous solution with a detection limit of 0.2 μM, which is much lower than the permissible limit of Al(III) set by the World Health Organization (WHO).The probe works in a wide pH range (4-11) and thus makes it a suitable candidate for environmental and biological applications. The fluorescence signals of R were used to construct an INHIBIT molecular logic gate. The confocal fluorescence microscope experiments show that R could be employed as a fluorescent probe for detecting Al(III) in living cells.

中文翻译：

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用于水溶液中Al（III）选择性开启荧光检测的多位探针：合成，阳离子结合，配位模式，逻辑门和细胞成像。

具有多种连接位点的易于制备的有机探针（以下称为R）已经合成并使用光谱技术表征。探针在二甲基甲酰胺（DMF）（1：1 v / v）水溶液中对Al（III）表现出选择性和敏感的开启荧光响应。荧光滴定实验表明该探针与Al（III）的化学计量比为1：1，结合常数为6.6×104 M-1。通过27Al和1H NMR建立了R与Al（III）的配位模式研究和结果表明，形成了八面体复合体。R与Al（III）的建议连接点通过密度泛函理论（DFT）优化的结构和计算的Mulliken电荷得到了很好的证实。螯合增强荧光（CHEF）被提出作为向R中添加Al（III）增强荧光的机理。该探针以0.2μM的检测限检测水溶液中的Al（III），该检测限远低于世界卫生组织（WHO）设定的Al（III）的允许极限。该探针可在很宽的pH范围（4-11）中工作，因此使其成为环境和生物应用的合适候选者。R的荧光信号用于构建INHIBIT分子逻辑门。共聚焦荧光显微镜实验表明，R可以作为荧光探针用于检测活细胞中的Al（III）。该探针远低于世界卫生组织（WHO）设定的Al（III）允许极限。该探针可在很宽的pH范围（4-11）中工作，因此使其非常适合环境和生物应用。R的荧光信号用于构建INHIBIT分子逻辑门。共聚焦荧光显微镜实验表明，R可以作为荧光探针用于检测活细胞中的Al（III）。该探针远低于世界卫生组织（WHO）设定的Al（III）允许极限。该探针可在很宽的pH范围（4-11）中工作，因此使其非常适合环境和生物应用。R的荧光信号用于构建INHIBIT分子逻辑门。共聚焦荧光显微镜实验表明，R可以作为荧光探针用于检测活细胞中的Al（III）。