Unique Tri-Output Optical Probe for Specific and Ultrasensitive Detection of Hydrazine

Abstract

An optical probe based on colorimetric and ratiometric as well as chemiluminometric signal outputs is developed for the specific detection of hydrazine. On the basis of a Gabriel-type reaction, hydrazinolysis of a simple probe CF (4-phtalamide-<i>N</i>-(4′-methylcoumarin) naphthalimide) produces both the fluorescence of 7-amino-4-methylcoumarin with the max emission wavelength changed from 480 to 420 nm (along with a color change from yellow to transparent) and the luminol chemiluminescence activated by H₂O₂ with a max emission wavelength at 450 nm. The experimental detection limit of hydrazine is 3.2 ppb (0.1 μM). Selectivity experiments proved CF has excellent selectivity to hydrazine over other interfering substances. Probe CF was also successfully applied in the vapor hydrazine detection over other interfering volatile analytes. Furthermore, the probe CF loaded thin-layer chromatography (TLC) plate for vapor hydrazine detection limit is 5.4 mg/m³ which is well below the half lethal dose of hydrazine gas for mice (LC₅₀(mice), 330 mg/m³) and National Institute of Occupational Safety and Health’s immediately dangerous to life or health limit (NIOSHIDLH, 66 mg/m³). With H₂O₂, only hydrazinolysis product luminol can be lighted at 450 nm, other species have no signal. Probe CF can also be used for the detection of hydrazine in HeLa cells