An effective benzothiazole-indandione D-π-A fluorescent sensor for “ratiometric” detection of hydrazine: Its solvatochromism properties and applications in environmental samples and living cells

A cellulose based fluorescent microsphere for sensitive detection and efficient removal of hydrazine and its versatile applications in environmental samples and live plants.

Hypochlorite (ClO-), a potent oxidizer and disinfectant, and hydrazine, a powerful reducing agent, are widely used in daily life and various industries. However, their extensive use comes with significant risks, as they are highly toxic to both the environment and human health. They have been associated with various health issues and even linked to cancer. Therefore, the simultaneous detection of hypochlorite and hydrazine is crucial for assessing their impact and monitoring the onset and progression of related diseases. A phenanthroimidazole-indandione based colorimetric and ratiometric fluorescent probe PIID was designed and synthesized for dual channel detection of hypochlorite and hydrazine in environmental and biological samples. Probe PIID, which showed a strong yellow-orange emission at 640 nm with a massive Stokes shift of 220 nm, exhibited excellent fluorescence change from yellow-orange to green (526 nm) in the presence of ClO- and from yellow-orange to blue (424 nm) in the presence of hydrazine in an aqueous-THF solvent system. A strong ICT effect, which was acting in probe PIID, gets weakened through ClO- - mediated cleavage of the CC bridge bond to produce aldehyde PIB with a blue shift of 114 nm and hydrazine-induced hydrazinolysis of the indanedione moiety to form hydrazone compound PIBH with a blue shift of 216 nm and that was also confirmed by DFT studies. Not only that, the probe exhibits excellent selectivity over other ROS (reactive oxygen species) and amines with a very fast response time of 40 seconds for hypochlorite and 90 seconds for hydrazine, and high sensitivity was observed with detection limits of 32.75 nM for hypochlorite and 92 nM for hydrazine. Moreover, PIID was employed to monitor both the analytes successfully in environmental water samples and in a solid-state TLC strip study. Hypochlorite was monitored in commercial disinfectants, and by exogenous bioimaging in human breast cancer cells (MDA-MB 231) and endogenous bioimaging in RAW 264.7 macrophage cells with very low cytotoxicity and good cell viability. Meanwhile, hydrazine was tracked in soil samples, and confocal imaging was performed on onion tissue.

A dual-platform phenothiazine-based fluorescent probe for hydrazine (N2H4) bioimaging in multiple organisms and smartphone-assisted environmental monitoring.

Hydrazine (N2H4) is an important industrial raw material that has been widely used in industrial production and agricultural interventions, but its widespread application also inevitably causes environmental pollution. In this study, based on resorufin, we constructed a novel "turn-on" fluorescent probe RFT for the selective detection of hydrazine under complex environmental conditions and in vivo. The probe RFT exhibited excellent stability and selectivity towards the detection of hydrazine with a low detection limit of 260 nM. In addition, RFT was successfully applied to the detection of hydrazine in environmental water samples and living cells. Most importantly, RFT could not only detect the exogenous hydrazine in zebrafish and mice, but also image and visualize the up-regulation of endogenous hydrazine induced by isoniazid in zebrafish.

Hydrazine is carcinogenic and highly toxic so that it can lead to serious environmental contamination and serious health risks although it has been extensively used as an effective propellant and an important reactive base in industry. Thus, the development of two-emission NIR fluorescent probes for rapid detection of hydrazine with high selectivity and sensitivity is of significance and of great challenge in both biological and environmental sciences. Here, we report a two-emission colorimetric fluorescent probe for the specific detection of hydrazine based on hydrazinolysis reaction under physiological conditions. In the presence of hydrazine, the probe showed an extremely remarkable fluorescence enhancement at 627 nm compared to the decrease at 814 nm excited at different wavelength in aqueous solution. This distinct difference of two emission intensities is suitable for detection of low concentration hydrazine with a detection limit of 0.38 ppb. Addition of hydrazine resulted in a remarkable color change from blue-green to red observed by the naked eye. Kinetic study indicated a fast response of the probe toward hydrazine in minutes. Furthermore, the probe can bioimage hydrazine in living HeLa cells and mice with low cytotoxicity and excellent biocompatibility.

A solvent directed D-π-A fluorescent chemodosimeter for selective detection of hazardous hydrazine in real water sample and living cell

An environmentally friendly turn-on ethyl cellulose-based fluorescent sensor with high selectivity and sensitivity for detection of hydrazine and its applications in biological and environmental systems.

A reduced graphene oxide/platinum(II) tetraphenylporphyrin nanocomposite (RGO/Pt‐TPP)‐modified glassy carbon electrode was developed for the selective detection of hydrazine. The RGO/Pt‐TPP nanocomposite was successfully prepared via noncovalent π–π stacking interaction. The prepared nanocomposite was characterized using nuclear magnetic resonance, electrochemical impedance, ultraviolet–visible and Raman spectroscopies, scanning electron microscopy and X‐ray diffraction. The electrochemical detection of hydrazine was performed via cyclic voltammetry and amperometry. The RGO/Pt‐TPP nanocomposite exhibited good electrocatalytic activity towards detection of hydrazine with low overpotential and high oxidation peak current. The fabricated sensor exhibited a wide linear range from 13 nM to 232 μM and a detection limit of 5 nM. In addition, the fabricated sensor selectively detected hydrazine even in the presence of 500‐fold excess of common interfering ions. The fabricated electrode exhibited good sensitivity, stability, repeatability and reproducibility. In addition, the practical applicability of the sensor was evaluated in various water samples with acceptable recoveries.

Design and synthesis of dual-excitation fluorescent probe, Tb3+-dtpa-bis(fluorescein), and application in detection of hydrazine in environmental water samples and live cells

Pyrazole probes for the detection of N2H4 with ICT properties in live cells and soils

Push-pull intramolecular charge transfer solvatofluorochromic fluorophore for the selective and real-time detection of hydrazine

Fabrication of a novel gold nanospheres/activated carbon nanocomposite for enhanced electrocatalytic activity toward the detection of toxic hydrazine in various water samples

A distinctive merocyanine-based fluorescent probes for the detection of phosgene and hydrazine.

This study explored the application of ddPCR and qPCR methods in identifying Naegleria fowleri from both clinical and environmental water samples. Strong agreement between ddPCR and qPCR methods over clinical DNA samples was observed. Naegleria fowleri was present in surface water samples from Lake Pontchartrain during our study period. The ability of N. fowleri to survive in brackish water is therefore a potential risk factor for people who engage in water-related recreational activities. The ddPCR performance demonstrated in this study on clinical and environmental samples lead to greater confidence of ddPCR technology on field application.

To determine whether Mycobacterium avium subsp paratuberculosis could be isolated from soil-pasture, faecal, water and sediment samples on farms before and after removal of sheep with paratuberculosis. A feasibility study and subsequent field survey. First the analytical sensitivity of radiometric culture of the organism from two types of soil was determined relative to faeces. Then soil-pasture, faecal, water and sediment samples were collected for culture from a range of sites from 6 farms with paratuberculosis affected sheep and goats. Similar samples were collected from 20 farms at least 9 months after removal of infected stock. The analytical sensitivity of culture of M a paratuberculosis from soil samples was 2 orders of magnitude less than that from faeces, and environmental samples required longer incubation periods to yield significant growth in radiometric culture (BACTEC) medium. However, the organism was recovered from approximately 20% of 163 soil-pasture, water and sediment samples from 6 properties with clinically-affected animals with paratuberculosis. The positive samples were from a range of topographic sites, including open exposed and dry areas, however, low lying areas tended to have larger numbers of organisms. When the same sites were sampled again about 5 months later, only 1 was culture positive, and none were culture positive > 12 months later. Of 17 water and dam sediment samples collected from farm 6, which had long-standing high prevalence OJD infection, only one water sample and one sediment from the same dam were culture positive. None of the 5 water samples from the other farms were culture positive. Of 96 water samples, 90 sediment samples and 93 soil samples from farms that had been destocked of infected sheep/goats for 9 to 24 months, one sediment sample from a farm in Victoria (destocked for 12 months) and two sediment samples from a farm in New South Wales (10, 19 months) were culture positive. Recontamination from cattle or water could not be excluded as a cause of the positive cultures from the second farm. M a paratuberculosis can be detected by radiometric culture in environmental samples from farms grazed by sheep or goats with paratuberculosis. There is a relatively low likelihood of recovery of the organism from water samples from such farms, and at 5 or more months after removing stock with paratuberculosis the likelihood of positive cultures from environmental samples is very low. Although the analytical sensitivity of culture from environmental samples is less than that from faeces, surveys of environmental sites are nevertheless feasible. However, improved culture methods are needed for critical surveys and to study the movement and fate of the organism in the environment.