Chen Zhiqiang, Lv Wenchao, Yang Chen, Ping Meiling, Fu FengFu
Key Laboratory for Analytical Science of Food Safety and Biology of MOE, Fujian Provincial Key Lab of Analysis and Detection for Food Safety, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350116, China; College of Food and Biological Engineering, Zhangzhou Institute of Technology, Zhangzhou, Fujian 36300, China.
Key Laboratory for Analytical Science of Food Safety and Biology of MOE, Fujian Provincial Key Lab of Analysis and Detection for Food Safety, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350116, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Dec 15;283:121734. doi: 10.1016/j.saa.2022.121734. Epub 2022 Aug 10.
Free copper ions (Cu and Cu) have critical toxicity to cells, although copper is an essential element for human body. Hence, sensitive monitoring is crucial to avoid over intake of Cu/Cu. We herein designed a ssDNA sequence (A) for synthetizing A-templated silver nanoclusters (AgNCs), and demonstrated that Cu/Cu can induce the aggregation of A-templated AgNCs and thus greatly enhanced the fluorescence emission of A-templated AgNCs. Based on Cu/Cu-induced fluorescence enhancement effect of A-templated AgNCs, a label-free and signal-on fluorescent sensing platform was developed for the specific and sensitive detection of Cu/Cu in biological samples and intracellular imaging of Cu/Cu in cells. The signal-on fluorescent sensing platform could be used to rapidly detect Cu and Cu with a detection limit of 0.1 µM within 30 min., and to perform the intracellular imaging of Cu and Cu in cells with good cell permeability and biocompatibility. By using the signal-on fluorescent sensing platform, we have successfully detected Cu and Cu in cells fluids and human serum with a recovery of 90-104% and a RSD (n = 5) < 5%, and performed the imaging of Cu/Cu in Hela cells. The developed fluorescent sensing platform has obvious analytical and imaging advantages such as signal-on, simple operation, short analysis time, both Cu and Cu detection, similar or higher sensitivity, good cell permeability and biocompatibility, which promising a reliable approach for the rapid and on-site detection or imaging of free copper ions in biological samples in clinical diagnosis.
游离铜离子（Cu⁺和Cu²⁺）对细胞具有关键毒性，尽管铜是人体必需元素。因此，灵敏监测对于避免过量摄入Cu⁺/Cu²⁺至关重要。我们在此设计了一种用于合成A模板化银纳米簇（AgNCs）的单链DNA序列（A），并证明Cu⁺/Cu²⁺可诱导A模板化AgNCs聚集，从而极大增强A模板化AgNCs的荧光发射。基于Cu⁺/Cu²⁺诱导的A模板化AgNCs荧光增强效应，开发了一种无标记且信号开启的荧光传感平台，用于生物样品中Cu⁺/Cu²⁺的特异性灵敏检测以及细胞内Cu⁺/Cu²⁺成像。该信号开启的荧光传感平台可在30分钟内快速检测Cu⁺和Cu²⁺，检测限为0.1 μM，并能对细胞内的Cu⁺和Cu²⁺进行成像，具有良好的细胞通透性和生物相容性。通过使用该信号开启的荧光传感平台，我们成功检测了细胞液和人血清中的Cu⁺和Cu²⁺，回收率为90 - 104%，相对标准偏差（n = 5）< 5%，并在Hela细胞中进行了Cu⁺/Cu²⁺成像。所开发的荧光传感平台具有明显分析和成像优势，如信号开启、操作简单、分析时间短、可同时检测Cu⁺和Cu²⁺、灵敏度相似或更高、细胞通透性和生物相容性良好，有望成为临床诊断中生物样品中游离铜离子快速现场检测或成像的可靠方法。
