Dipartimento di Scienze Chimiche, Università di Catania, I-95125 Catania, Italy.
Sensors (Basel). 2023 Apr 12;23(8):3925. doi: 10.3390/s23083925.
The development of chemosensors able to detect analytes in a variety of sample matrices through a low-cost, fast, and direct approach is of current interest in food, health, industrial, and environmental fields. This contribution presents a simple approach for the selective and sensitive detection of Cu ions in aqueous solution based on a transmetalation process of a fluorescent substituted Zn(salmal) complex. Transmetalation is accompanied by relevant optical absorption changes and quenching of the fluorescence emission, leading to high selectivity and sensitivity of the chemosensor, with the advantage of not requiring any sample pretreatment or pH adjustment. Competitive experiments demonstrate a high selectivity of the chemosensor towards Cu with respect to the most common metal cations as potential interferents. A limit of detection down to 0.20 μM and a dynamic linear range up to 40 μM are achieved from fluorometric data. By exploiting the fluorescence quenching upon formation of the copper(II) complex, simple paper-based sensor strips, visible to naked eyes under UV light, are used for the rapid, qualitative, and quantitative in situ detection of Cu ions in aqueous solution over a wide concentration range, up to 10.0 mM, in specific environments, such as in industrial wastewater, where higher concentrations of Cu ions can occur.
能够通过低成本、快速和直接的方法在各种样品基质中检测分析物的化学传感器的发展，在食品、健康、工业和环境领域引起了人们的兴趣。本贡献提出了一种基于荧光取代 Zn(salmal)配合物的转金属化过程，用于选择性和灵敏检测水溶液中 Cu 离子的简单方法。转金属化伴随着相关的光学吸收变化和荧光发射的猝灭，导致化学传感器具有高选择性和灵敏度，其优点是不需要任何样品预处理或 pH 调整。竞争实验证明，该化学传感器对 Cu 具有很高的选择性，相对于最常见的金属阳离子作为潜在的干扰物。从荧光数据中得到了低至 0.20 μM 的检测限和高达 40 μM 的动态线性范围。通过利用形成铜（II）配合物时的荧光猝灭，可以在特定环境（例如工业废水中）中使用肉眼可见的基于荧光的简单纸质传感器条带，在很宽的浓度范围内（高达 10.0 mM），快速、定性和定量原位检测水溶液中的 Cu 离子。
