A turn-on fluorescent probe 1 has been developed for Cu²⁺ by the incorporation of picolinate onto a tricyanofuran-based fluorophore. The probe was weakly fluorescent due to the masked phenolic group and the resulted inhibition of the push-pull character of the fluorophore. The chemoselective reaction of probe 1 with Cu²⁺ leads to a dramatic fluorescence enhancement at 610 nm via the Cu²⁺-mediated hydrolysis of picolinate moiety and the subsequent release of the highly emissive fluorophore. This probe features high selectivity for Cu²⁺ over other cations, as well as high sensitivity with a low detection limit of 54 nM. Moreover, cell cytotoxicity and imaging tests indicate that probe 1 is biocompatible and can be utilized for imaging Cu²⁺ in live cells.

通过将吡啶甲酸根结合到基于三氰呋喃的荧光团上，已开发出一种用于Cu ²⁺的开启式荧光探针1。由于被掩蔽的酚基团和导致的荧光团推挽特性的抑制，探针的荧光较弱。探针1与Cu ²⁺的化学选择性反应通过Cu ²⁺介导的吡啶甲酸部分的水解和随后的高发射荧光团的释放，导致在610 nm处发生显着的荧光增强。该探针具有对Cu ^2+的高选择性与其他阳离子相比，灵敏度高，检出限低至54 nM。此外，细胞的细胞毒性和成像测试表明，探针1具有生物相容性，可用于对活细胞中的Cu ²⁺进行成像。