A new colorimetric and far-red fluorescent probe for hydrazine with a large red-shifted absorption spectrum

Recently, growing attention has been paid to the detection of hydrazine (NH₂ NH₂ ) because of its important roles in industrial chemical and high toxicity to human beings. Herein, we have constructed a new colorimetric and far-red fluorescent probe containing a receptor of 4-bromobutanoate to selectively detect hydrazine. The probe could detect hydrazine quantitatively in the range of 40-500 μM with the detection limit of 2.9 μM. In addition, the probe could monitor hydrazine by the ratiometric method with a large (185 nm) red-shifted absorption spectrum, and the color changes from yellow to blue make it as a 'naked-eye' indicator for hydrazine. Consequently, our proposed probe would be of great benefit for monitoring hydrazine in aqueous solution.