Department of Studies in Physics, Karnatak University Dharwad, Karnataka, 580003, India.
Department of Physics, BLDE Association's S.B Arts and KCP Science college Vijayapura, Karnataka, 586103, India.
J Fluoresc. 2020 Sep;30(5):1025-1033. doi: 10.1007/s10895-020-02573-4. Epub 2020 Jun 30.
Herein, a novel notion is used to reuse an expired drug namely Telmisartan (Sensor 2) to optically sense the Fe metal ion. Direct re-usage of the drug avoided wearisome procedures of synthesis, hence proved the method as simple and economic. Sensor 2 found highly stable in the temperature range 25-75 °C. Relative fluorescence was almost the same even after 35 days of observation. There were no significant changes in wavelength even after adding different concentrations of FeCl, which shows the high stability of the compound. The value of Limit of Detection (LOD) observed was 34.2 nM. FTIR studies confirmed the presence of carboxylic group. The method of fluorescence quenching was used to detect the Fe ion. The association between Sensor 2 and Fe was analyzed using Benesi-Hildebrand relation. Positive deviation from the linearity of S-V plots suggested that the quenching was not purely dynamic. Further, this deviation was analyzed by the sphere of action quenching model. To investigate whether the quenching is diffusion limited, we applied the finite sink approximation model and deduced that quenching is due to both static and dynamic processes. Due to the high fluorescence property of the molecule, it was successfully tested to be used as fluorescent ink.
在此，提出了一种新颖的概念，即将一种过期药物替米沙坦（Sensor 2）重新用于光学检测 Fe 金属离子。直接重新使用该药物避免了繁琐的合成程序，因此证明了该方法既简单又经济。传感器 2 在 25-75°C 的温度范围内非常稳定。即使观察 35 天后，相对荧光强度几乎相同。即使加入不同浓度的 FeCl，波长也没有明显变化，这表明该化合物具有很高的稳定性。观察到的检测限（LOD）值为 34.2 nM。FTIR 研究证实了羧酸基团的存在。荧光猝灭法用于检测 Fe 离子。使用 Benesi-Hildebrand 关系分析传感器 2 和 Fe 之间的相互作用。S-V 图的线性偏离表明猝灭不是纯粹的动态过程。进一步，通过作用球猝灭模型分析了这种偏离。为了研究猝灭是否受扩散限制，我们应用有限阱近似模型，并推断猝灭是由静态和动态过程共同引起的。由于分子具有高荧光性质，它已成功测试可用于荧光墨水。
