A new phenoxazine-indanedione turn-on fluorescent probe with ultra-sensitivity for detecting hydrazine and its application in drinks, human urine and water samples and colorimetric test strips

Abstract

Considering that hydrazine (N2H4) is a suspected carcinogen and shows severe toxicity to ecological and human health, thus, the effective detection of N2H4 is an urgent need throughout the globe. In this work, a new phenoxazine-indanedione turn-on fluorescent probe PI was developed and applied for visually/ultra-sensitively monitoring N2H4 in aqueous media. A brilliant green fluorescence lighting-up response of probe PI was achieved upon the N2H4 adding. The N2H4 detection by probe PI shows significant advantages of high-specificity, favorable pH working range (3 ∼ 11), and ultra-sensitivity with an extreme low-detection-limit (0.85 nM). The mechanism for N2H4 detection was ascribed to the N2H4-induced C = C breakage, which was proved by the spectral means and DFT investigations. Probe PI-laden silica-gel, and paper/TLC strips were conveniently constructed for on-site and real-time visual monitoring gaseous and aqueous N2H4, demonstrating its potential application value. More importantly, the PI could accurately and ultra-sensitively monitor trace amounts of N2H4 in real samples such as drinks, water and human urine with high precision. Overall, this work provided a new valuable turn-on fluorescent probe for ultra-sensitively detecting N2H4.