Gajendhiran Ramalingam, Raees Ahmed Abbas Khaja, Mithra Sivaraj, Abdul Majeed Seepoo, Sahul Hameed Azeez Sait, Muthu Kesavan, Sarathkumar Sankar, Nehru Selvan, Rahiman Aziz Kalilur
Post-Graduate and Research Department of Chemistry, The New College, University of Madras, Chennai 600014, India.
Post-Graduate and Research Department of Zoology, Aquatic Animal Health Laboratory, C. Abdul Hakeem College, Melvisharam 632509, India.
ACS Omega. 2024 Dec 18;9(52):50957-50977. doi: 10.1021/acsomega.4c04001. eCollection 2024 Dec 31.
Four dual-responsive probe molecules 1,5-bis(thiophene-2-carbaldehyde)carbohydrazone (R1), 1,5-bis(thiophene-2-carbaldehyde)thiocarbohydrazone (R2), 1,5-bis(indole-3-carbaldehyde)carbohydrazone (R3), and 1,5-bis(indole-3-carbaldehyde)thiocarbohydrazone (R4) were synthesized, characterized, and investigated for their sensing efficacy. The initial sensing behavior of the probes was tested by colorimetric signaling, followed by spectral and theoretical techniques, which supported the dual-sensing ability of the selected inorganic ions. The probes exhibited highly selective optical recognition for Cu/Fe cations and F/ClO anions compared to the tested cations and anions. Interestingly, the addition of Cu and F ions to the probes resulted in "turn-on" fluorescence responses. Job's plot studies showed 1:2 stoichiometry between the probe molecules and cations and 1:1 stoichiometry between the probe molecules and anions. The binding constant of the probe molecules with the sensed ions was determined by the Benesi-Hildebrand equation and was found to be between 7.08 × 10 and 7.44 × 10 M with a limit of detection between 0.11 and 0.80 μM, in CHCN:DMF (9:1, v/v). Density functional theory calculations established the nature of the interaction between the probe molecules and sensed ions. Further, the practical utility of the probes was successfully demonstrated with paper strip experiments, fluorescence imaging of Cu ions in G cells and zebrafish larvae, as well as in the development of molecular logic gates.
合成了四种双响应探针分子1,5-双（噻吩-2-甲醛）碳腙（R1）、1,5-双（噻吩-2-甲醛）硫代碳腙（R2）、1,5-双（吲哚-3-甲醛）碳腙（R3）和1,5-双（吲哚-3-甲醛）硫代碳腙（R4），对其进行了表征，并研究了它们的传感效果。通过比色信号测试探针的初始传感行为，随后采用光谱和理论技术，这些技术支持了所选无机离子的双传感能力。与测试的阳离子和阴离子相比，这些探针对Cu/Fe阳离子和F/ClO阴离子表现出高度选择性的光学识别。有趣的是，向探针中加入Cu和F离子会导致“开启”荧光响应。Job曲线研究表明，探针分子与阳离子之间的化学计量比为1:2，探针分子与阴离子之间的化学计量比为1:1。通过Benesi-Hildebrand方程确定了探针分子与传感离子的结合常数，发现在CHCN:DMF（9:1，v/v）中，结合常数在7.08×10至7.44×10 M之间，检测限在0.11至0.80 μM之间。密度泛函理论计算确定了探针分子与传感离子之间相互作用的性质。此外，通过纸条实验、G细胞和斑马鱼幼虫中Cu离子的荧光成像以及分子逻辑门的开发，成功证明了这些探针的实际应用价值。
