A near-infrared fluorescent probe for selective detection of fluorion

In this work, we have designed and synthesized the fluorescent probe 1, which was capable to selectively detect fluoride anion (F⁻). More importantly, the probe 1 possessed near-infrared excitation and emission wavelengths (excitation at 650 nm and emission at 695), and the probe solution had changed dramatically from yellow to cyan with the addition of F^–. In addition, the fluorescence intensity exhibited perfectly positive correlation with concentration of F⁻ concentration from 0 to 40 μM (R² = 0.9972), which offered the important condition for quantitative analysis. The probe 1 owned detection limit of 46 nM. Therefore, this near-infrared probe can be of great benefit for detecting F⁻ in practical application.