A new phenothiazine-thiophene hydrazone based ((10-ethyl-10H-phenothiazine-3,7-diyl)bis(methanylylidene))bis(thiophene-2-carbohydrazide) (PHT) chemosensor was synthesized via a single-step reaction and utilized as fluorescence “On-Off” sensor towards Hg²⁺ ion. The PHT was fully characterized by FT-IR, ¹H-NMR, and ESI-Mass spectral analysis. The PHT probe was efficiently used for the selective detection of Hg²⁺ ion in the presence of other metal ions. Further, the stoichiometry of the PHT with Hg²⁺ complex was confirmed by Job’s plot analysis. The limit of detection (LOD) value of the probe PHT was found to be 0.44 × 10⁻⁸ M.

Graphical abstract

中文翻译：

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吩噻嗪-噻吩肼衍生物：一种高效的“开关”化学传感器，用于Hg 2+离子的高选择性和灵敏检测

通过一步反应合成了一种新的吩噻嗪-噻吩（（（10-乙基-10 H-吩噻嗪3,7-二基）双（甲萘））双（噻吩2-咔肼）（PHT）化学传感器。用作对Hg ²⁺离子的荧光“开-关”传感器。该PHT被完全表征通过FT-IR，¹ H-NMR，和ESI-质谱分析。该PHT探针有效地用于汞的选择性检测²⁺离子在其他金属离子的存在。此外，通过乔布氏图分析证实了具有Hg ^2+配合物的PHT的化学计量。探头PHT的检测极限（LOD）值被发现是0.44×10 ^-8  M.

图形概要