Two novel water‐soluble fluorescence probes T1 and T2 based on 5(6)‐carboxyl rhodamine were designed and synthesized using a regioselective reaction. The probes exhibited highly selective and sensitive recognition toward Cu²⁺ over other metal ions in acetonitrile/Tris–HCl buffer solution (2:98, v/v; pH 7.4). Detection limits were 0.4 μM for T1 and 4.50 μM for T2 based on fluorescence titration analysis. Furthermore, probe T1 was successfully applied in cell imaging experiments to monitor Cu²⁺ in cells.

中文翻译：

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两个基于5（6）-羧基若丹明的水溶性荧光探针，用于活细胞中的Cu2 +成像。

使用区域选择性反应设计并合成了两种基于5（6）-羧基若丹明的新型水溶性荧光探针T1和T2。相对于乙腈/ Tris-HCl缓冲溶液（2：98，v / v； pH 7.4）中的其他金属离子，探针对Cu ²⁺表现出高度选择性和敏感性。根据荧光滴定分析，T1的检测限为0.4μM ，T2的检测限为4.50μM 。此外，探针T 1已成功应用于细胞成像实验中，以监测细胞中的Cu ²⁺。