An effective colorimetric chemosensor, 2,4-dichloro-6-((E)-(((Z)-3-methylbenzo[d]thiazol-2(3H)-ylidene)hydrazono)methyl)phenol (HMD), was synthesised for Cu²⁺ detection. HMD with benzothiazole moiety showed a large bathochromic shift (153 nm) and a definite colour change for Cu²⁺. HMD could detect Cu²⁺ down to 0.47 Î¼mol/L in the solution phase and could clearly distinguish it from other metal ions, even in the test strip. The binding mode between HMD and Cu²⁺ was determined to be 1:1 using Job plot and electrospray ionisation mass spectrometry. The sensing mechanism of HMD for Cu²⁺ was illustrated as the combination of metal-to-ligand charge transfer and intramolecular charge transfer via theoretical calculation.

中文翻译：

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基于苯并噻唑部分检测Cu2+的有效比色传感器

合成了一种有效的比色化学传感器，2,4-二氯-6-((E)-(((Z)-3-methylbenzo[d]thiazol-2(3H)-ylidene)hydrazono)methyl)phenol (HMD)用于 Cu ²⁺检测。带有苯并噻唑部分的 HMD 显示出较大的红移 (153 nm) 和 Cu ²⁺的明确颜色变化。HMD 可以检测溶液相中低至 0.47 μmol/L 的Cu ²⁺并且可以清楚地区分它与其他金属离子，即使在试纸中也是如此。使用工作图和电喷雾电离质谱法确定HMD 和 Cu ²⁺之间的结合模式为 1:1。HMD对Cu ²⁺的传感机制 通过理论计算将金属-配体电荷转移和分子内电荷转移结合起来。