Faculty of Chemistry and Pharmacy, Sofia University "St. Kliment Ohridski", 1 J. Baurchier blvd., 1164 Sofia, Bulgaria.
Faculty of Medicine, Sofia University "St. Kliment Ohridski", 1 Koziak str., 1407 Sofia, Bulgaria.
Sensors (Basel). 2020 Jul 13;20(14):3892. doi: 10.3390/s20143892.
Three new 1,8-naphthalimide derivatives - with different substituents at the C-4 position have been synthesized and characterized. Their photophysical properties have been investigated in organic solvents of different polarity, and their fluorescence intensity was found to depend strongly on both the polarity of the solvents and the type of substituent at C-4. For compounds and having a tertiary amino group linked via an ethylene bridge to the chromophore system, high quantum yield was observed only in non-polar media, whereas for compound , the quantum efficiency did not depend on the medium polarity. The effect of different metal ions (Ag, Ba, Cu, Co, Mg, Pb, Sr, Fe, and Sn) on the fluorescence emission of compounds and was investigated. A significant enhancement has been observed in the presence of Ag, Pb, Sn, Co, Fe, as this effect is expressed more preferably in the case of . Both compounds have shown significant pH dependence, as the fluorescence intensity was low in alkaline medium and has been enhanced more than 20-fold in acidic medium. The metal ions and pH do not affect the fluorescence intensity of . Density-functional theory (DFT) and Time-dependent density-functional theory (TDDFT) quantum chemical calculations are employed in deciphering the intimate mechanism of sensor mechanism. The functional properties of and were compared with polyamidoamine (PAMAM) dendrimers of different generations modified with 1,8-naphthalimide.
已经合成并表征了三个新的 1,8-萘二甲酰亚胺衍生物 - 它们在 C-4 位置具有不同的取代基。研究了它们在不同极性有机溶剂中的光物理性质，发现它们的荧光强度强烈依赖于溶剂的极性和 C-4 上取代基的类型。对于通过乙烯桥连接到生色团系统的具有叔氨基的化合物 和 ，仅在非极性介质中观察到高量子产率，而对于化合物 ，量子效率不依赖于介质极性。研究了不同金属离子（Ag、Ba、Cu、Co、Mg、Pb、Sr、Fe 和 Sn）对化合物 和 的荧光发射的影响。在存在 Ag、Pb、Sn、Co、Fe 的情况下观察到显著增强，这种效应在 的情况下表现得更为明显。这两种化合物都表现出显著的 pH 依赖性，因为在碱性介质中荧光强度较低，而在酸性介质中增强了 20 多倍。金属离子和 pH 不影响 的荧光强度。密度泛函理论（DFT）和时变密度泛函理论（TDDFT）量子化学计算被用于破译传感器机制的内在机制。比较了 和 与不同代数的聚酰胺胺（PAMAM）树枝状聚合物的功能特性，这些树枝状聚合物用 1,8-萘二甲酰亚胺修饰。
