Rajalakshmi Kanagaraj, Muthusamy Selvaraj, Lee Ho-Jin, Kannan Palanisamy, Zhu Dongwei, Silviya Lodi Rathna, Xie Meng, Xie Jimin, Song Jong-Won, Xu Yuanguo
School of Chemistry and Chemical Engineering, School of Pharmacy, Jiangsu University, Zhenjiang 212013, China.
School of Chemistry and Chemical Engineering, School of Pharmacy, Jiangsu University, Zhenjiang 212013, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2024 Jan 5;304:123282. doi: 10.1016/j.saa.2023.123282. Epub 2023 Aug 19.
Substitution can be employed to competently tune the photophysical properties of chemosensors. The effect of substituents on the absorption and emission properties of quinoline probes was investigated. Therefore, salicylaldehyde (S), N-diethylamino-salicylaldehyde (D), and nitro-salicylaldehyde (W)-based quinoline Schiff base derivatives were investigated with hydrazine and studied for their photophysical properties. The nucleophilic substitution reaction was used as a sensing mechanism between the probes and hydrazine and investigated with H NMR, HR-MS characterizations, and DFT calculations. The sensitivity of QW-R is greater than that of QS-R and QD-R because of the stronger intramolecular charge transfer (ICT) in QW-R. The calculated LOD values are 28 nM for QS-R, 30 nM for QD-R, and 9 nM for QW-R. The probes were employed to monitor gaseous hydrazine using a smartphone and analyze solution forms of hydrazine in soil, water, and food samples, and living cells. Moreover, the in situ hydrazine release was monitored with bioimaging by administering an isoniazid drug. Significantly, the electronic effect of substituents over fluorescence showing, ranging from electron-donating to electron-withdrawing was investigated. We anticipate that this approach may be a promising strategy for the rational design of fluorescent sensors.
取代作用可用于有效调节化学传感器的光物理性质。研究了取代基对喹啉探针吸收和发射性质的影响。因此，以水杨醛（S）、N - 二乙氨基水杨醛（D）和硝基水杨醛（W）为基础的喹啉席夫碱衍生物与肼进行了反应，并对其光物理性质进行了研究。亲核取代反应被用作探针与肼之间的传感机制，并通过核磁共振氢谱（¹H NMR）、高分辨质谱（HR-MS）表征和密度泛函理论（DFT）计算进行了研究。由于QW - R中分子内电荷转移（ICT）更强，QW - R的灵敏度高于QS - R和QD - R。计算得到的检测限（LOD）值分别为：QS - R为28 nM，QD - R为30 nM，QW - R为9 nM。这些探针被用于使用智能手机监测气态肼，并分析土壤、水、食品样品和活细胞中肼的溶液形式。此外，通过施用异烟肼药物，利用生物成像监测原位肼释放。值得注意的是，研究了取代基从供电子到吸电子对荧光的电子效应。我们预计这种方法可能是荧光传感器合理设计的一种有前途的策略。
