Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China.
Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an, 710072, China.
Anal Bioanal Chem. 2019 Sep;411(23):6165-6172. doi: 10.1007/s00216-019-02007-6. Epub 2019 Jul 16.
The copper(II) ion (Cu) has played an indispensable role in diverse kinds of functional physiological processes of organisms, which has become of growing interest. Despite the fact that numerous Cu test papers using fluorescent probes have been fabricated, sensors featuring the ratiometric property that integrates quenched probes and an inner standard dye are rarely reported. Herein, a two-component ratiometric sensor in a paper-based device is proposed to realize highly selective Cu detection. To overcome shortcomings such as low signal-to-noise ratio and incorrect response of the quenching probe, a novel BODIPY-based turn-off probe (P2017) is designed and introduced into the paper-based device with better water solubility and selectivity for Cu detection. Furthermore, a reference dye (B001), exhibiting an emission at 690 nm when the excitation wavelength is 480 nm, is also introduced into the paper-based device. These two components can enhance the quality of the signal as P2017 is sensitively quenched by Cu, while B001 with a photostable property, serving as an internal benchmark, is unable to react with Cu. The results indicated that the two components provided a new concept for optimizing paper-based device fabrication and developing accurate, simple, and inexpensive Cu detection methods, which could be potentially applied to monitor human health and the environment in remote areas. Graphical abstract.
铜（II）离子（Cu）在生物体的各种功能生理过程中发挥了不可或缺的作用，这一点引起了越来越多的关注。尽管已经制备了许多使用荧光探针的 Cu 试纸，但很少有报道具有比率性质的传感器，该性质将猝灭探针和内标染料集成在一起。本文提出了一种基于纸片的两组件比率传感器，以实现对 Cu 的高选择性检测。为了克服猝灭探针的信噪比低和响应不正确等缺点，设计并引入了一种基于 BODIPY 的新型关闭探针（P2017），该探针具有更好的水溶性和对 Cu 检测的选择性，被引入到纸片装置中。此外，还引入了一种参考染料（B001），当激发波长为 480nm 时，其发射波长在 690nm 处。这两个组件可以增强信号的质量，因为 P2017 被 Cu 灵敏地猝灭，而具有光稳定性的 B001 作为内标，不能与 Cu 反应。结果表明，这两个组件为优化纸片装置的制造和开发准确、简单和廉价的 Cu 检测方法提供了一个新概念，该方法可能应用于监测偏远地区的人类健康和环境。
