Detection Of N2H4 Research Articles

A Ratiometric Fluorescent Probe for N2H4 Having a Large Detection Range Based upon Coumarin with Multiple Applications.

Although hydrazine (N2H4) is a versatile chemical used in many applications, it is toxic, and its leakage may pose a threat to both human health and environments. Consequently, the monitoring of N2H4 is significant. This study reports a one-step synthesis for coumarin-based ratiometric fluorescent probe (FP) CHAC, with acetyl as the recognition group. Selected deprotection of the acetyl group via N2H4 released the coumarin fluorophore, which recovered the intramolecular charge transfer process, which caused a prominent fluorescent, ratiometric response. CHAC demonstrated the advantages of high selectivity, a strong capacity for anti-interference, a low limit of detection (LOD) (0.16 μM), a large linear detection range (0-500 μM), and a wide effective pH interval (6-12) in N2H4 detection. Furthermore, the probe enabled quantitative N2H4 verifications in environmental water specimens in addition to qualitative detection of N2H4 in various soils and of gaseous N2H4. Finally, the probe ratiometrically monitored N2H4 in living cells having low cytotoxicity.

1,8-naphthalimide-triphenylamine-based red-emitting fluorescence probes for the detection of hydrazine in real water samples and applications in bioimaging in vivo

Hydrazine (N2H4), as a highly reducing agent and reactive base, is extensively utilized in chemical, pharmaceutical and agriculture fields. However, the high toxicity of N2H4 poses significant risks to human health and can lead to severe ecological contamination. Consequently, it is of significant to develop a tool for the detection of N2H4 in the environment fields and in vivo. Herein, three 1,8-naphthalimide-triphenylamine-based red-emitting fluorescence probes (TSY-1, TSY-2 and TSY-3) have been developed for the detection of N2H4 in actual water sample and in vivo by coupling of 1,8-naphthalimide derivatives with the electron-withdrawing groups (1,3-indandione, malononitrile, and 2-benzothiazolethonitrile) through a N2H4 responsive CC bond. Significant fluorescence quenching of three probes was observed on account of the responses toward N2H4. The detection limits of TSY-1, TSY-2 and TSY-3 for N2H4 were calculated to be 0.2 μM, 0.4 μM and 54 μM, respectively. Utilizations of probe-based test paper strips to qualitatively detect N2H4 in actual water sample by “naked-eye” colorimetry were demonstrated. Additionally, quantitative determination of N2H4 in actual water samples was successfully achieved by the smartphone-based standard curves. Additionally, the applications of TSY-1, TSY-2 and TSY-3 in fluorescence imaging N2H4in vivo are also demonstrated.

A fluorescent probe based on modulation of ESIPT signaling for the highly selective detection of N2H4 and cell-imaging

The broad occurrence of the hydrazine (N2H4) residues in aqueousenvironment is a potential threat to human health. Currently, the mainstream strategy for designing N2H4-specific probes is to functionalize a fluorophore with nucleophilic sites for the reductionreaction with N2H4. In this work, we designed and synthesized an excited-state intermolecular proton transfer (inter-ESPT) fluorescent dye(2-amino-4-(4-methoxyphenyl)-7,8-dihydro-5H-spiro[quinoline-6,2′-[1,3]dioxolane]-3-carbonitrilem, DQN) and used it as a probe to sense N2H4. DQN exhibits blue fluorescence in conventional solvents, which is assigned to its normal emission. In the presence of N2H4, the probe DQN can anchor the N2H4 molecule via hydrogen binding, enabling DQN to undergo inter-ESPT process and light up its tautomeric fluorescence. From this basis, an inter-ESPT-based method for N2H4 detection was established, offering high selectivity and sensitivity (11.5 nM). Furthermore, we demonstrated that the probe DQN can recognize the proteins in living cells, affording cell-imaging. This research provides a promising sensing strategy for monitoring N2H4 in water environments and this inter-ESPT dye is a powerful tool for cell-imaging.

A turn-on fluorescent probe for sensing N2H4 in living cells, zebrafishes and plant root with a large turn-on fluorescence signal

Hydrazine (N2H4) plays an important role in industrial production, but it is highly toxic, leaking or exposing it will pollute the environment and cause serious harm to human beings. Therefore, it is necessary to use a simple and effective method to detect N2H4 in environmental systems and organisms. Herein, a novel water-soluble fluorescent probe based on coumarin fluorophore, 2-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)isoindoline-1,3-dione (C-Z1), is reported. The fluorescence intensity of the probe at 530 nm was enhanced gradually with the addition of N2H4, and the maximum enhancement was about 28 times. The probe has good selectivity and sensitivity, the detection limit of hydrazine hydrate is 1.48 × 10−7 M, and the response mechanism of the probe is proved by theoretical calculation and experiment. C-Z1 has been shown to detect N2H4 in a variety of environmental samples, including water, soil, air, cells, zebrafish and plants. In addition, C-Z1 can be made into test strips for easy portability and used for rapid quantitative detection of N2H4 in the field by its distinct change in fluorescence color. Thus, C-Z1 has great potential for the analysis and detection of environmental contaminants.

Water-soluble single molecular probe for simultaneous detection of viscosity and hydrazine.

Hydrazine (N2H4) can cause serious damage to human health, while intracellular viscosity is highly associated with many diseases and cellular dysfunctions. Herein, we report the synthesis of a dual-responsive organic molecule-based fluorescent probe with excellent water solubility being capable of detection of N2H4 and viscosity through dual-fluorescence channels in "turn on" manner for both. Besides sensitive detection of N2H4 in aqueous solution with detection limit of 0.135μM, this probe could be used for vapor N2H4 detection in colorimetric and fluorescent manners. In addition, the probe demonstrated viscosity-dependent fluorescence enhancement behavior, and as high as 150-fold enhancement could be obtained at 95% glycerol aqueous solution. Cell imaging experiment revealed that the probe could be used for the discriminating of living and dead cells.

Fast, visual, and quantitative monitoring of N2H4 by two ratiometric fluorescent probes in environmental media and biological systems

Hydrazine (N2H4) is a toxic compound widely used in agricultural, chemical, pharmaceutical, and other industrial processes. It causes serious pollution to air, soil, and water. Therefore, the detection of N2H4 is one of the prime scientific interests. In this study, two novel reaction-based ratiometric fluorescence probes (Phe-HBT and Me-HBT) for the selective and sensitive detection of N2H4 are reported. The present approach, including the cyclization reaction induced by N2H4, enables to visualization of N2H4 at low levels by naked eyes under daylight or UV light with a fast response time of about 8.0 min for Phe-HBT and 16.0 min for Me-HBT. The detection limits of the probes were calculated to be 80.6 nM for Phe-HBT and 99.2 nM for Me-HBT. Both the probes displayed high specificities for N2H4 among the tested potential competing analytes. Both probes were applied to detect aqueous trace N2H4 in various samples such as food, soil, sewage water and living cells. Moreover, the detection of N2H4 was successfully tested by smartphone application as well as the detection of gaseous N2H4 by the modified fabric, showing its potential value in practical applications.

Two Benzocoumarin-based hydrazine chemodosimeters and their application in monitoring trace levels of hydrazine in soil, water, and urine samples

Hydrazine is used widely in various sectors. This intensified environmental degradation during storage, transit, and sewage disposal. Hydrazine, a category 2B toxin, can go into the body via the skin and nasal passages. It could permanently harm the body. Developing selective recognition mechanisms is critical. In this study, two reaction-based sensors, Coumarin- benzobromobutanoate (CnBr) and Coumarin-Chalcone (CnBC) were developed for the selective detection of N2H4. When exposed to N2H4, CnBr and CnBC in H2O/DMSO (1:1) both produced green fluorescence with highest emission at 528 nm and 532 nm, respectively. The absence of a buffer would greatly simplify and facilitate real-time sample sensing. The addition-cyclisation-elimination cascade reaction supports the sensing mechanism for both CnBr and CnBC, as confirmed by 1H NMR and ESI-MS data. Other ions, amines, and amino acids didn't affect the probes’ hydrazine detection. CnBr and CnBC detects N2H4 at 1.05 µM and 1.01 µM respectively. The probe's practical application was demonstrated by its capacity to sense hydrazine in different soil samples, real water, and urine samples.

Synthesis and applications of a corrole-based dual-responsive fluorescent probe for separate detection of hydrazine and hydrogen sulfide

Here, a corrole-based dual-responsive fluorescent probe DPC-DNBS was rationally designed and synthesized for the separate detection of hydrazine (N2H4) and hydrogen sulfide (H2S) with high selectivity and sensitivity. The probe DPC-DNBS is intrinsically none fluorescent due to PET effect, however, addition of increasing amount of N2H4 or H2S to DPC-DNBS turned on an excellent NIR fluorescence centered at 652 nm and thereby provided a colorimetric signaling behavior. The sensing mechanism was verified by HRMS, 1H NMR and the DFT calculations. Common metal ions and anions do not interfere with the interactions of DPC-DNBS with N2H4 or H2S. Furthermore, the presence of N2H4 does not affect the detection of H2S; however, the presence of H2S interferes with the detection of N2H4. Hence, quantitative detection of N2H4 must occur in an H2S-free environment. The probe DPC-DNBS displayed some fascinating merits in separate detection of these two analytes, including large Stokes shift (233 nm), fast response (15 min for N2H4, 30 s for H2S), low detection limit (90 nM for N2H4, 38 nM for H2S), wide pH range (6–12) and outstanding biological compatibility. Significantly, DPC-DNBS was utilized to detect hydrazine in real water, soil and food samples. And its favorable performances for separate detection N2H4 and H2S were successfully demonstrated in HeLa cells and zebrafish, indicating its value of practical application in biology.

Theoretical Insights on the Sensing Performance for Newly-synthesized Two-photon Fluorescent N2H4 Probes Based on Spirobifluorence.

The development of fluorescent probe for hydrazine (N2H4) detection has attracted much attention due to the important role of N2H4 plays in the fields of medicine, agriculture, biology and environments. In this paper, the optical properties and water solubility of two novel two-photon fluorescent molecular probes (Probe1 and Probe2) before and after the reaction with N2H4 are studied by using the density function theory. The results show that electronic distribution and transition dipole moment of the probes are obviously changed after the reaction with N2H4, thus the optical properties of the molecules are influenced and the detection of N2H4 are realized. In addition, photoinduced electron transfer processes for Probe1 and Probe2 in the presence of N2H4 are theoretically characterized, which explains the experimental observations from the microscopic mechanism. Special attention has been paid on the analysis of the two-photon absorption for the probes with the absence and presence of N2H4 by the response theory method. Both probes with good water solubility show large variation on the two-photon absorption cross section when reacts with N2H4. In particular, the two-photon absorption response of Probe2 is more obvious, so it possesses preferable two-photon fluorescence microscopic imaging ability. More importantly, the receptor effect on the sensing performances of the probes are demonstrated, providing a theoretical reference for the design and synthesis on more efficient two-photon fluorescence N2H4 probes. Our study provides necessary information on the response mechanism of the studied chemosensors and helps to establish the relationship between the structure and optical properties of two-photon fluorescence N2H4 probes.

A dual-emission fluorescence probe for the detection of viscosity and hydrazine in environmental and biological samples

The microenvironments of biological systems are associated with the pathology of organisms. This study, aimed to construct a hemicyanine-based probe (1), which can respond to mitochondrial viscosity and hydrazine (N2H4), for imaging application in living cells and zebrafish. The probe showed no fluorescence due to the intramolecular rotation in the solution; however, it exhibited a strong emission at 730 nm when the molecules were restricted to a high-viscosity environment. The addition of N2H4 caused an elimination reaction of the N-substituted group in the pyridinium part and further broke the CC bond to produce a highly fluorescent hydrazone. Also, the probe could selectively and quantitatively detect N2H4 via the fluorescence enhancement at 510 nm in a concentration range of 0 μM–140μM, with the limit of detection being 0.0485 μM. This probe may be used to study diseases related to N2H4 and viscosity changes in biological systems. Furthermore, the analysis methods based on probe 1 for N2H4 detection in soil, water, and air samples were successfully established.

Multi-scene visual hydrazine hydrate detection based on a dibenzothiazole derivative.

Hydrazine (N2H4) produced by industries is distributed into different environments, and seriously threatens ecology and human security. Hence, it is important to develop probes that detect N2H4 in various environments. In this study, a novel N2H4 fluorescent probe was prepared based on a dibenzothiazole derivative (DBTD). The obtained DBTD probe demonstrated a strong ratio of colorimetric detection of N2H4, a rapid response, and good selectivity and sensitivity (detection limit 0.438 μM). Based on its good performance, the DBTD probe was successfully applied for the determination of trace N2H4 in water, cells, and zebrafish. In addition, the results of the fluorescence colocalization experiment demonstrated the lysosomal-targetable ability of DBTD.

Electrochemical Sensors Based on Au Nanoparticles Decorated Pyrene-Reduced Graphene Oxide for Hydrazine, 4-Nitrophenol and Hg2+ Detection in Water.

Monitoring hazardous chemical compounds such as hydrazine (N2H4), 4-nitrophenol (4-NP) and Hg2+ in natural water resources is a crucial issue due to their toxic effects on human health and catastrophic impact on the environment. Electrochemical nanostructured platforms integrating hybrid nanocomposites based on graphene derivatives and inorganic nanoparticles (NPs) are of great interest for such a purpose. In this work, disposable screen-printed carbon electrodes (SPCEs) have been modified with a hybrid nanocomposite formed by reduced graphene oxide (RGO), functionalized by 1-pyrene carboxylic acid (PCA), and decorated by colloidal Au NPs. These hybrid platforms have been tested for the electrocatalytic detection of N2H4 and 4-NP by differential pulse voltammetry and have been modified with an electropolymerized film of Hg2+ ions imprinted polycurcumin for the electroanalytical detection of Hg2+ by DPV. LODs, lower and in line with the lowest ones reported for state-of-the-art electrochemical sensors, integrating similar Au-graphene < nanocomposites, have been estimated. Additionally, good repeatability, reproducibility, and storage stability have been assessed, as well as a high selectivity in the presence of a 100-fold higher concentration of interfering species. The applicability of the proposed platforms for the detection of the compounds in real complex matrices, such as tap and river water samples, has been effectively demonstrated.

Facile pyrolysis synthesis of Pt-PtFe nanoparticles/3D porous N-doped carbon nanoflowers for highly sensitive detection of hydrazine and bisphenol A

It is still challenging for synthesis of advanced nanomaterials and explores their electrocatalytic detection of hydrazine (N2H4) and bisphenol A (BPA). Herein, Pt-PtFe nanoparticles/three-dimensional (3D) porous N-doped carbon nanoflowers (Pt-PtFe/N-CNFs) were successfully prepared by high-temperature pyrolysis. The structures and properties of the nanocomposite were strictly investigated by various characterization techniques. The Pt-PtFe/N-CNFs displayed high-efficiency electrocatalytic activity for oxidation of N2H4 and BPA. Under the optimal conditions, the Pt-PtFe/N-CNFs based sensor exhibited the wide linear ranges: 0.5–559.5 μM and 559.5–2659.5 μM for detection of N2H4 with a limit of detection (LOD) of 0.19 μM (S/N = 3), coupled with a broad scope of 0.3–70 μM and a LOD of 0.043 μM for BPA. The developed sensor has promising applications in environmental and industrial samples.

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

Hydrazine (N2H4) has high toxic impact and is widely used as raw material. As a result, it poses serious health risks and the following environmental pollution. Therefore, hydrazine's detecting techniques remains constantly under investigation. Herein, we report a ratiometric D-π-A fluorescent probe displaying NIR emission based on the ICT mechanism to detect N2H4. Other tested analytes have no observable interferences on the sensitivity and selectivity. The probe has sensitivity for N2H4 down to 1.29 μM with quick detection time (about 2.0 min). Moreover, the probe demonstrates solvatochromism with obvious emission varying from dull red to green, which implied high sensitivity to medium polarity. A portable smartphone platform for point-of-care detection of N2H4 in water samples is constructed. As a proof of real samples, the probe is successfully applied to sense N2H4 in water samples, to bioimage N2H4 in living cells and in plant cells with low cytotoxicity, suggesting significant potential application. This strategy opens up the preparation of new ratiometric fluorescence systems for bioimaging and environmental monitoring applications.

A smartphone-adaptable chromogenic and fluorogenic sensor for rapid visual detection of toxic hydrazine in the environment

Hydrazine is an essential chemical in industries, but its high toxicity poses great threats to human health and environmental safety. Hence, it is of great significance to monitor the hydrazine in environment. In this work, we presented a chromogenic and fluorogenic dual-mode sensor RA for the detection of hydrazine based on nucleophilic substitution reaction. A linear relationship was obtained between the fluorescence intensity and the concentrations of N2H4 ranging from 0 to 35 μM (R2 = 0.9936). The sensor can determine hydrazine with fast response (within 12 min), low limit of detection (0.129 μM) and high selectivity. RA was successfully used to detect N2H4 in real water samples with good recoveries and the results corresponded to the standard method. Furthermore, the sensor-coated portable test papers were fabricated, which can visually quantify hydrazine solutions with obvious fluorescence transformation from colorless to red. Moreover, RA-loaded papers were used to create a smartphone-adaptable RGB values analytical method for quantitative N2H4 detection.

A dual-ratiometric mitochondria-targeted fluorescent probe to detect hydrazine in soil samples and biological imaging

Hydrazine (N2H4) is carcinogenic, extremely toxic, and induces serious environmental contamination and physiological dysfunction; however, it is widely used as an industrial material. Hence, the development of a simple and effective analytical method to detect N2H4 detection in both environmental and biological sectors is warranted. In this work, an intramolecular charge transfer (ICT)-based fluorescent probe 1, namely (Z)− 1-(4-acetoxybenzyl)− 4-(1-cyano-2-(7-(diethylamino)− 2-oxo-2 H-chromen-3-yl)vinyl)pyridin-1-ium, was designed for dual-excitation (420 and 600 nm, excitation separations >160 nm), near infrared (NIR)-emissive, and ratiometric fluorescent detection of N2H4. The sensing behavior of probe 1 for N2H4 detection was shown to be available over a wide pH range, and detection limits of 68 nM and 569 nM were achieved at excitation wavelengths of 420 and 600 nm, respectively. In addition, probe 1 was successfully used to image mitochondrial N2H4 in living cells and zebrafish. Furthermore, the probe was also capable of determining hydrazine signals in test strips and environmental soil.

High-sensitivity amperometric hydrazine sensor based on AuNPs decorated with hollow-structured copper molybdenum sulfide nanomaterials

Hollow-structured hybrid nanomaterials were superior electrocatalysts on account of their unique structures and preeminent properties. This study showed the synthesis of Au decorated with hollow-structured Cu2MoS4 (H-CMS) nanohybrid via hydrothermal and chemical reduction methods. Furthermore, novel hydrazine (N2H4) electrochemical sensor was fabricated based on the as-prepared nanocomposites. The characterization results revealed that homogeneous AuNPs with an average diameter of 13 nm were anchored on the surface and internal cavity of hollow CMS spheres. In addition, the sensor exhibited some excellent electrochemical performance for N2H4 detection. The linear range obtained by the as-proposed sensor was 0.02–377.7 μM, a much lower detection limit with 7 nM (S/N＝3), and a higher sensitivity with 440.1 μA mM−1 cm−2. The linear range of the sensor was maintained at the same level as the widest or better in some cases compared with the similar type of N2H4 sensors previously reported. At least two orders of magnitude reduced the detection limit of the as-proposed sensor. It was about 21-fold lower than that of the TiO2 @PANI@Au/glassy carbon electrode (GCE) sensor with the lowest detection limit. A factor of 1.5 times improved the sensitivity compared with the analogous type Au-Fe3O4-GO/GCE sensor. Additionally, the Au/H-CMS/GCE sensor displayed fast responses, high selectivity, and superior stability for N2H4 detection.

Ionic liquid-assisted synthesis of 2D porous lotus root slice-shaped NiO nanomaterials for selective and highly sensitive detection of N2H4

The sensitive and effective detection of Hydrazine (N2H4), a highly toxic compound, has been urgently required to ensure safe manufacture and physical health. In this work, a 2D porous lotus root slice-shaped NiO material was prepared by the ionic liquid-assisted hydrothermal method of 1-hexadecyl-3-methylimidazole chloride with regulated calcination temperature, and the characterization was exclusively confirmed through TG, XRD, SEM, TEM, XPS, and other test methods. The gas-sensing test results demonstrated that the small amount of ionic liquid residues in the NiO material after being calcined at 700 °C significantly improved its gas-sensing performance to N2H4 gas. The fabricated sensor achieved a response value of 107.6–100 ppm N2H4 at an optimal working temperature of 92 °C, a recovery time of 29.6 s, with the lowest detection limit of 10 ppb. In addition, we further analyzed the sensing mechanism of NiO materials to N2H4 gas through XPS and gas chromatography-mass spectrometry.

Fe-doped carbonized polymer dot-based fluorescent sensor with "turn-on" property for hydrazine hydrate detection.

It has become a significant problem to develop and improve carbonized polymer dot (CPD)-based fluorescence sensors with environmental detection features. In this study, fluorescent "turn on" sensors of CPDs were prepared by a one-step hydrothermal method using o-phenylenediamine (o-PD) and ferric chloride (FeCl3) as raw materials. Fe-doped CPDs exhibited excellent fluorescence properties, stability, and the sensitive and selective "turn on" detection of hydrazine hydrate (N2H4·H2O). In this detection system, Fe3+ acts as an effective fluorescence inhibitor that inhibits the yellow fluorescence emission from CPDs, while Fe3+ is reduced upon the addition of the N2H4·H2O reducing agent. The fluorescence intensity of CPDs gradually increased with the increasing concentration of N2H4·H2O, while the limit of detection (LOD) could reach 0.168 μM. In addition, CPD-based polyvinyl alcohol (CPDs@PVA) films were also prepared, which still maintained excellent sensitivity to N2H4·H2O. The results show that CPDs and their composite films can detect N2H4·H2O with good detection performance.

A novel dual-response triphenylamine-based fluorescence sensor for special detection of hydrazine in water

A novel-fluorescent sensor named TPAPI, is designed and constructed successfully. In DMSO/H2O (pH = 7.4) system, the TPAPI sensor demonstrates two different fluorescent responsive properties with the water volume fraction (fw): At 90%, the TPAPI shows an aggregation induced emission (AIE) effect around 670 nm, and can be used as a turn-off sensor; Meanwhile, at 10%, based on the fluorescent property of titration product, the aggregation caused quenching (ACQ) type fluorescent sensor can be constructed around 470 nm with LOD at 1.37 × 10−7 mol·L−1. The TPAPI sensor exhibits outstanding selectivity, anti-interference for hydrazine among thirty molecules and ions. The sensing mechanism is attributed to the formation of hydrazone (TPAP-N2H4), confirmed by LC-MS. Theoretical calculations further confirm TPAPI molecules possess AIE property and TPAP-N2H4 has the ACQ character. In addition, the TPAPI test strip can be prepared and applied successfully for the detection of N2H4.