Ilakiyalakshmi Mohan, Dhanasekaran Kumudhavalli, Roopan Selvaraj Mohana, Napoleon Ayyakannu Arumugam
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India.
J Fluoresc. 2025 Apr 15. doi: 10.1007/s10895-025-04276-0.
The detection of sulfide ions in environmental and biological systems has garnered significant interest, but finding probes that combine rapid response with high selectivity remains difficult. Despite progress, the quest for efficient sulfide detection methods is still ongoing. This article introduces the synthesis and development of the ratiometric fluorescent probe PTZ-ICN, utilizing the phenothiazine framework to address the challenge of selective detection. The PTZ-ICN probe's structural integrity and spectral properties were confirmed via FT-IR, ¹H-NMR, ¹³C-NMR, and HRMS analyses. PTZ-ICN exhibits remarkable selectivity and sensitivity towards sulfide ions (S²⁻), even in the presence of competing anions, within a DMSO: HEPES buffer system (9:1, v/v). The interaction between the PTZ-ICN probe and sulfide ions was thoroughly analyzed using Job's plot, HRMS, ¹H-NMR titration, and DFT analysis. The PTZ-ICN probe successfully quantified sulfide ions with a detection limit as low as 11.63 nM, demonstrating a strong linear correlation (R² = 0.99941). Moreover, PTZ-ICN has shown great utility in real-time scenarios, including the detection of sulfide ions in water samples, test strips, solid-state platforms, and living A549 cells. This study emphasizes PTZ-ICN's significant promise for real-world applications in environmental monitoring and bioimaging, establishing it as a valuable probe for reliable sulfide detection across diverse environments.
在环境和生物系统中检测硫化物离子已引起了广泛关注，但找到能将快速响应与高选择性相结合的探针仍然困难重重。尽管取得了进展，但对高效硫化物检测方法的探索仍在继续。本文介绍了比率荧光探针PTZ-ICN的合成与开发，利用吩噻嗪框架来应对选择性检测的挑战。通过傅里叶变换红外光谱（FT-IR）、核磁共振氢谱（¹H-NMR）、核磁共振碳谱（¹³C-NMR）和高分辨质谱（HRMS）分析，证实了PTZ-ICN探针的结构完整性和光谱特性。即使在存在竞争性阴离子的情况下，在二甲基亚砜：HEPES缓冲液体系（9:1，v/v）中，PTZ-ICN对硫化物离子（S²⁻）也表现出显著的选择性和灵敏度。使用Job曲线、HRMS、¹H-NMR滴定和密度泛函理论（DFT）分析，对PTZ-ICN探针与硫化物离子之间的相互作用进行了深入分析。PTZ-ICN探针成功地对硫化物离子进行了定量，检测限低至11.63 nM，显示出很强的线性相关性（R² = 0.99941）。此外，PTZ-ICN在实时场景中表现出了很大的实用性，包括在水样、试纸条、固态平台和活的A549细胞中检测硫化物离子。这项研究强调了PTZ-ICN在环境监测和生物成像的实际应用中的巨大潜力，使其成为在各种环境中可靠检测硫化物的有价值的探针。
