First Dual Responsive “Turn‐On” and “Ratiometric” AIEgen Probe for Selective Detection of Hydrazine Both in Solution and the Vapour Phase

A novel bifunctional-group salamo-like multi-purpose dye probe based on ESIPT and RAHB effect: Distinction of cyanide and hydrazine through optical signal differential protocol

A novel bifunctional-group multi-purpose dye probe p-TNS has been designed and synthesized. The probe p-TNS has unique excited-state intramolecular proton transfer (ESIPT) and resonance-assisted hydrogen bonding (RAHB) coupled system, was confirmed to detect cyanide and hydrazine by blocking the ESIPT effect. Cyanide can change the fluorescence of the solution from bright green to orange-red (116 nm Stokes shift), while hydrazine causes the bright green fluorescence to be quenched. The recognition mechanism of the probe p-TNS to CN^- and N₂H₄ was proposed reasonably through spectral characterizations and theoretical calculations. Combined with theoretical calculations, it was speculated that the solvent dependence may be caused by the ICT effect in the molecule. The probe p-TNS could be prepared into test strips for the detection of cyanide and hydrazine. In addition, the probe molecule can also be used to detect trace amounts of cyanide in agricultural products, and respond to gaseous hydrazine by direct contact, indicating that the probe p-TNS has good practical application prospects. Therefore, this molecular framework provides a new way of thinking about detecting multiple target substances.

Introduction of a luminescent sensor for tracking trace levels of hydrazine in insect pollinated cropland flowers

Introduction of an efficient chemodosimeter (NCD) to estimate the mutagenic hydrazine within several affected cropland flowers promptly showing ‘turn-on’ fluorescence.

A dual-response ratiometric fluorescent probe for hypochlorite and hydrazine detection and its imaging in living cells

In this work, a dual-response ratiometric fluorescent probe (E)-3-(5-(2-nitrovinyl)thiophen-2-yl)-9-phenyl-9H-carbazole (NTPC) for high selectivity and sensitivity detection of ClO^- and N₂H₄ was successfully developed. This probe NTPC showed ratiometric fluorescent response to ClO^- and N₂H₄, which induces obvious naked-eye color changes, respectively. In addition, the NTPC for ClO^- and N₂H₄ detection displayed low detection limits of 71.4 nM and 0.6 μM, respectively. And the sensing mechanism of NTPC with ClO^- and N₂H₄ was well confirmed by ¹H NMR and HR-MS spectra. Moreover, this novel probe was applied to monitoring and differentiating ClO^- and N₂H₄ in living cells, and exhibits good biocompatibility and low cytotoxicity.

A coumarin-fused 'off-on' fluorescent probe for highly selective detection of hydrazine

Hydrazine is a kind of widely used industrial raw material and a toxic biochemical reagent. Due to its toxic to organisms, hydrazine has been classified to be a hazardous environmental pollutant. It is urgent to develop fluorescent probe tools for selective sensitivity detection of hydrazine in the environment and the body. We developed here a new coumarin-based fluorescent probe for hydrazine detection. The probe can selectively detect hydrazine over other environmental and endogenous interfering analytes with a large off-on fluorescence response. The detection limit is 8.55 ppb, which is well below the allowed threshold limit value. The sensing mechanism is hydrazine-induced pyrazole ring formation, which is confirmed by HRMS and DFT calculation methods. Additionally, the probe could also be applied for hydrazine imaging in living HeLa cells.

Metal-free polycycloaddition of aldehyde-activated internal diynes and diazides toward post-functionalizable poly(formyl-1,2,3-triazole)s

A metal-free polycycloaddition of aldehyde-activated internal diynes and diazides was successfully established and post-functionalizable poly(formyl-1,2,3-triazole)s were readily produced.

Rapid switch-on fluorescent detection of nanomolar-level hydrazine in water by a diacetoxy-functionalized MOF: application in paper strips and environmental samples

A diacetoxy-functionalized Zr-based metal–organic framework was employed for the selective, ultra-sensitive, turn-on fluorescent detection of hydrazine in an aqueous medium.

Tetrathienylethene-based Positional Isomers with Aggregation-induced Emission Enabling Super Red-shifted Reversible Mechanochromism and Naked-eye Sensing of Hydrazine Vapor

AIE-active positional isomers, TTE-o-PhCHO, TTE-m-PhCHO and TTE-p-PhCHO, tetrathienylethene (TTE) derivates with peripherally attached ortho-/meta-/para-formyl phenyl groups, were designed and synthesized. The formyl substitution position can effectively modulate their photophysical properties, mechanochromism and fluorescent response to hydrazine. TTE-o-PhCHO and TTE-m-PhCHO exhibit remarkable AIE characteristics, and TTE-p-PhCHO possesses aggregation-induced emission enhancement performance. They all exhibit high contrast mechanochromism, and TTE-m-PhCHO shows larger red-shift (164 nm) than TTE-o-PhCHO (104 nm) and TTE-p-PhCHO (125 nm) due to the more twisted molecular conformation and much looser molecular packing. Moreover, TTE-o-PhCHO with a higher contrast color change can be used as ink-free rewritable paper. In addition, TTE-p-PhCHO, as a turn-on fluorescent probe, can selectively detect hydrazine with significant color changes that are visible by the naked eye . Therefore, the position dependence of groups would be an effective method to modulate the molecular arrangement, as well as develop AIE compounds for mechano-stimuli responsive materials, ink-free rewritable papers and chemosensors.