Herein, a new probe, 5-methyl-1-pyridin-2-yl-1H-pyrazole-3-carboxylic acid (1-pyridin-2-yl-ethylidene)-hydrazide (Hmppc), bearing a pyridine–pyrazole moiety, was synthesized, which offered potential for chemical sensing of Al³⁺. Investigations of the fluorescence behaviour of Hmppc in DMSO/H₂O (2 : 8, v/v) solution under biologically relevant conditions in HEPES buffer (pH = 7.4) displayed a dramatic switch-on response to Al³⁺ as a result of chelation-induced enhanced fluorescence (CHEF). Detailed experimental studies reveal that Hmppc can detect Al³⁺ in solution with high sensitivity and selectivity, having a detection limit of 1.2 nM. Furthermore, to demonstrate the analytical potential of Hmppc, we validated our sensing system as a naked eye detector for Al³⁺. Interestingly, bioimaging studies on HepG2 cells demonstrated that Hmppc responded selectively towards Al³⁺, allowing real time detection of Al³⁺ in living cells.

中文翻译：

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由吡啶-吡唑体系构建 的新型荧光开启化学传感器，用于纳摩尔检测Al ³⁺ †

在这里，一个新的探针5-甲基-1-吡啶-2-基-1 H-吡唑-3-羧酸（1-吡啶-2-基-亚乙基）-酰肼（Hmppc），带有吡啶-吡唑部分合成了，为铝^3+的化学传感提供了潜力。在HEPES缓冲液（pH = 7.4）中，在生物学相关条件下，在DMSO / H ₂ O（2：8，v / v）溶液中Hmppc的荧光行为的研究显示，由于Al3 ⁺的显着接通反应螯合诱导的增强荧光（CHEF）。详细的实验研究表明，Hmppc可以检测Al ³⁺在具有高灵敏度和选择性的溶液中检测限为1.2 nM。此外，为了证明Hmppc的分析潜力，我们将传感系统验证为Al ³⁺的裸眼检测器。有趣的是，对HepG2细胞的生物成像研究表明，Hmppc对Al ³⁺有选择性的响应，从而可以实时检测活细胞中的Al ³⁺。