Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, School of Chemistry, South China Normal University, Guangzhou, 510006, Guangdong, China.
Mikrochim Acta. 2024 Oct 10;191(11):661. doi: 10.1007/s00604-024-06748-9.
By combining boric acid-modified carbon dots (p-CDs) and alizarin red (ARS), a double emission probe p-CDs@ARS with fluorescence at 410 nm and 600 nm is designed for the detection of glyphosate. When Cu is added, it binds with ARS to cause ARS release from p-CDs@ARS, which decreases the fluorescence at 600 nm. However, in the presence of glyphosate, glyphosate competes to the binding of Cu, releasing ARS to bind with p-CDs again. Therefore, the fluorescence of 600 nm recovers. Based on this, the fluorescence of 410 nm and 600 nm act as the reference and response signal, respectively, achieving the ratiometric fluorescence detection of glyphosate. The linear range of glyphosate detection is 0.5-50 µM with a limit of detection at 0.37 µM which is well below the maximum residue limit for glyphosate in food. When the probe is used to detect the glyphosate residue in Pearl River water and cucumber, the detection results are well consistent with those detected by HPLC. The established method based on p-CDs@ARS has the advantages that the assembly of ratiometric fluorescence probe is simple, and the detection speed is fast. Additionally, a typical INHIBIT logical system has been successfully constructed based on glyphosate, Cu, and the fluorescence signal of p-CDs@ARS.
通过将硼酸修饰的碳点（p-CDs）与茜素红（ARS）结合，设计了一种具有 410nm 和 600nm 荧光的双发射探针 p-CDs@ARS，用于检测草甘膦。当加入 Cu 时，它与 ARS 结合导致 ARS 从 p-CDs@ARS 中释放，从而降低了 600nm 处的荧光强度。然而，在存在草甘膦的情况下，草甘膦与 Cu 的结合竞争，将 ARS 释放出来并重新与 p-CDs 结合。因此，600nm 的荧光恢复。基于此，410nm 和 600nm 的荧光分别作为参考和响应信号，实现了草甘膦的比率荧光检测。草甘膦检测的线性范围为 0.5-50µM，检测限为 0.37µM，远低于食品中草甘膦的最大残留限量。当将探针用于检测珠江水中和黄瓜中的草甘膦残留时，检测结果与 HPLC 检测结果非常一致。基于 p-CDs@ARS 的建立方法具有以下优点：比率荧光探针的组装简单，检测速度快。此外，还成功地基于草甘膦、Cu 和 p-CDs@ARS 的荧光信号构建了一个典型的 INHIBIT 逻辑系统。
