Combination of imine bond and samarium emitter enables turn-off fluorescence detection of hydrazine in vapor and water samples

The development of convenient and efficient fluorescence techniques is of great significance for selective detection and precise determination of biotoxic N 2 H 4 in human health and environmental sciences. By the pre-organization-assisted template synthesis , disclosed here is a luminescent Sm(III) macrocycle-based probe Sm - 2 m bearing dynamic imine bonds as recognition moieties which provides the selective and ratiometric turn-off fluorescence sensing for N 2 H 4 over various amine species based on the N 2 H 4 -induced structure transformation. This fluorescent sensing process finished within 20 min shows the low limit of detection (0.18 μM, 7.2 ppb) and wide linear sensing range (0–60.0 μM). Furthermore, probe Sm - 2 m is also be used to quantitatively determine N 2 H 4 in vapor gas and water samples through fluorescence color changes, which are evaluated by the Sm - 2 m -impregnated test paper strips and RGB value outputs. Finally, our proposed smartphone-based analytical method gives satisfactory N 2 H 4 detection results. It is thus believed that this work can shed some lights on development of optical probes and detection techniques for N 2 H 4 , even other hazardous chemicals.