Dong Xuemei, Hu Zhongfei, Xiao Xuan, Zhang Keying, Ding Yujie
School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, 241000, Anhui, China.
Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes, School of Chemistry and Chemical Engineering, Suzhou University, Suzhou, 234000, Anhui, China.
J Fluoresc. 2025 Jun 14. doi: 10.1007/s10895-025-04398-5.
Excessive Cu levels pose severe threats to human health and ecosystems, necessitating sensitive and selective detection methods. A novel ratiometric fluorescent probe (CDs@RBH) based on fluorescence resonance energy transfer (FRET) was developed through electrostatic assembly. This nanoplatform employs carbon quantum dots (CDs) as the energy donor and rhodamine hydrazide (RBH) as the acceptor. Upon Cu addition, the spirolactam ring of RBH opens, triggering a distinct UV-Vis absorption peak at 550 nm, which overlaps with the emission spectrum of CDs (450 nm), enhancing FRET efficiency. This mechanism enables dual-signal readout: the fluorescence intensity of CDs at 450 nm decreases, while the RBH-Cu emission at 575 nm increases, allowing for precise ratiometric detection. The probe exhibits high selectivity and exceptional sensitivity, with a detection limit (LOD) of 0.65 μM and quantification limit (LOQ) of 2.09 μM. Practical applications in tap water samples demonstrate excellent recovery rates (96-108%). This work presents a straightforward synthesis method, environmental stability, and dual-channel signal verification for detection, making it a promising tool for real-world Cu monitoring in environmental and biological systems.
过量的铜含量对人类健康和生态系统构成严重威胁，因此需要灵敏且具有选择性的检测方法。通过静电组装开发了一种基于荧光共振能量转移（FRET）的新型比率荧光探针（CDs@RBH）。该纳米平台采用碳量子点（CDs）作为能量供体，罗丹明酰肼（RBH）作为受体。加入铜后，RBH的螺内酰胺环打开，在550 nm处引发一个明显的紫外-可见吸收峰，该峰与CDs的发射光谱（450 nm）重叠，提高了FRET效率。这种机制实现了双信号读出：450 nm处CDs的荧光强度降低，而575 nm处RBH-Cu的发射增强，从而实现精确的比率检测。该探针具有高选择性和出色的灵敏度，检测限（LOD）为0.65 μM，定量限（LOQ）为2.09 μM。在自来水样品中的实际应用显示出优异的回收率（96-108%）。这项工作提出了一种简单的合成方法、环境稳定性以及用于检测的双通道信号验证，使其成为环境和生物系统中实际铜监测的有前途的工具。
