Tetracycline (TC) is a broad-spectrum antibiotic used to treat bacterial infections. In this study, a ratiometric fluorescence (FL) probe was developed to detect TC in water samples using waste printing paper extract as a FL indicator. For this ratiometric probe, the emission of printing paper extract at 436 nm gradually decreased and the emission of a mixed solution at 538 nm significantly increased with the sequential addition of TC upon excitation at 390 nm, coupled with a marked FL colour change from bright blue to faint yellow. Therefore, a ratiometric F₅₃₈/F₄₃₆ FL probe was created for TC detection by simply mixing the printing paper extraction and TC. Under the optimized conditions, a linear range from 1 to 100 μM and a detection limit of 0.48 μM (S/N = 3) for TC were obtained. Importantly, the FL probe can be easily prepared with rapid response, high sensitivity, and good selectivity. The application of waste printing paper extract for detection of TC in environmental water samples was demonstrated.

中文翻译：

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基于废印刷纸的四环素比率荧光探针检测

四环素 (TC) 是一种广谱抗生素，用于治疗细菌感染。在本研究中，开发了一种比率荧光 (FL) 探针，以使用废印刷纸提取物作为 FL 指示剂检测水样中的 TC。对于这种比率探针，打印纸提取物在 436 nm 处的发射逐渐减少，而混合溶液在 538 nm 处的发射随着在 390 nm 激发时连续添加 TC 显着增加，再加上从亮蓝色到明显的 FL 颜色变化淡黄色。因此，比例式 F ₅₃₈ /F ₄₃₆通过简单地将打印纸提取物和 TC 混合，为 TC 检测创建了 FL 探针。在优化的条件下，获得了 1 至 100 μM 的线性范围和 0.48 μM (S/N = 3) 的 TC 检测限。重要的是，FL 探针可以很容易地制备，具有快速响应、高灵敏度和良好的选择性。论证了废印刷纸提取物在环境水样中TC检测的应用。