Detection of hydrazine based on Nano-Au deposited on Porous-TiO2 film

Recent Development on Sensing Strategies for Small Molecules Detections

Sensors play a critical role in the detection and monitoring of various substances present in our environment, providing us with valuable information about the world around us. Within the field of sensor development, one area that holds particular importance is the detection of small molecules. Small molecules encompass a wide range of organic or inorganic compounds with low molecular weight, typically below 900 Daltons including gases, volatile organic compounds, solvents, pesticides, drugs, biomarkers, toxins, and pollutants. The accurate and efficient detection of these small molecules has attracted significant interest from the scientific community due to its relevance in diverse fields such as environmental pollutants monitoring, medical diagnostics, industrial optimization, healthcare remedies, food safety, ecosystems, and aquatic and terrestrial life preservation. To meet the demand for precise and efficient monitoring of small molecules, this summary aims to provide an overview of recent advancements in sensing and quantification strategies for various organic small molecules including Hydrazine, Glucose, Morpholine, Ethanol amine, Nitrosamine, Oxygen, Nitro-aromatics, Phospholipids, Carbohydrates, Antibiotics, Pesticides, Drugs, Adenosine Triphosphate, Aromatic Amine, Glutathione, Hydrogen Peroxide, Acetone, Methyl Parathion, and Thiophenol. The focus is on understanding the receptor sensing mechanism, along with the electrical, optical, and electrochemical response. Additionally, the variations in UV-visible spectral properties of the ligands upon treatment with the receptor, fluorescence and absorption titration analysis for limit of detection (LOD) determination, and bioimaging analysis are discussed wherever applicable. It is anticipated that the information gathered from this literature survey will be helpful for the perusal of innovation regarding sensing strategies.

Novel electrochemiluminescence aptasensor based on AuNPs-ABEI encapsulated TiO2 nanorod for the detection of acetamiprid residues in vegetables

Gold nanoparticles (AuNPs)@N-(4-aminobutyl)-N-ethylisoluminol (ABEI)@Titanium dioxide nanorods (TiO2NRs) were used as sensing materials to produce a unique encapsulated nanostructure aptasensor for the detection of acetamiprid residues in this work. ABEI, an analog of luminol, was extensively used as an electrochemiluminescence (ECL) reagent. The ECL mechanism of ABEI- hydrogen peroxide (H2O2) system had connections to a number of oxygen-centered free radicals. TiO2NRs improved ECL response with high electron transfer and a specific surface area. AuNPs were easy to biolabel and could catalyze H2O2 to enhance ECL signal. AuNPs were wrapped around TiO2NRs by utilizing the reduction property of ABEI to form wrapped modified nanomaterials. The sulfhydryl-modified aptamer bound to the nanomaterial by forming gold-sulfur (Au-S) bonds. The aptamer selectively bound to its target with the addition of acetamiprid, which caused a considerable decrease in ECL intensity and enabled quantitative detection of acetamiprid. The aptasensor showed good stability, repeatability and specificity with a broad detection range (1×10-2-1×103 nM) and a lower limit of detection (3 pM) for acetamiprid residues in vegetables. Overall, this aptasensor presents a simple and highly sensitive method for ECL detecting acetamiprid, with potential applications in vegetable safety monitoring.

Unique Reaction-Based Polynorbornene Sensing Probes for Ultrasensitive Detection of Hydrazine in Both Environmental and Biological Systems

Hydrazine-mediated formation of 1,4-phthalazinedione analogues from phthalimide-like components has been utilized to formulate fluorescent probe NorTh. A turn-on fluorescent process has been evaluated to detect hydrazine in a highly selective manner by a small molecular probe NorTh and its homopolymer Poly-NorTh. Both these probes have been evaluated as excellent candidates for nanomolar level detection of hydrazine with a time frame of <15 min, which is rapid in terms of real application. Due to the reaction-based detection process, we have achieved high selectivity for our probes toward the identification of hydrazine in the presence of metal ions, anions, amino acids, and various amines. Limit of detection values are 16 and 35 nM for NorTh and Poly-NorTh, respectively, which are well below the permissible limit given by WHO and EPA. Poly-NorTh has been utilized to detect hydrazine in environmental water samples, soil samples, and biological samples to establish the applicability of our probes in real-field scenarios. We introduce an easy-to-synthesize, cheap, and small molecular probe and its polymer for ultrafast, highly selective, and sensitive detection of hydrazine in all possible mediums to counter the hydrazine toxicity through fluorescence turn-on signal output.

Lignosulfonate-Assisted In Situ Deposition of Palladium Nanoparticles on Carbon Nanotubes for the Electrocatalytic Sensing of Hydrazine

This paper presents a novel modified electrode for an amperometric hydrazine sensor based on multi-walled carbon nanotubes (MWCNTs) modified with lignosulfonate (LS) and decorated with palladium nanoparticles (NPds). The MWCNT/LS/NPd hybrid was characterized by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The electrochemical properties of the electrode material were evaluated using cyclic voltammetry and chronoamperometry. The results showed that GC/MWCNT/LS/NPd possesses potent electrocatalytic properties towards the electro-oxidation of hydrazine. The electrode demonstrated exceptional electrocatalytic activity coupled with a considerable sensitivity of 0.166 μA μM-1 cm-2. The response was linear from 3.0 to 100 µM L-1 and 100 to 10,000 µM L-1, and the LOD was quantified to 0.80 µM L-1. The efficacy of the modified electrode as an electrochemical sensor was corroborated in a study of hydrazine determination in water samples.

Review on application of perylene diimide (PDI)-based materials in environment: Pollutant detection and degradation

Environment pollution is getting serious and various poisonous contaminants with chemical durability, biotoxicity and bioaccumulation have been widespreadly discovered in municipal wastewaters and surface water. The detection and removal of pollutants show great significance for the protection of human health and other organisms. Due to its distinctive physical and chemical properties, perylene diimide (PDI) has received widespread attention from different research fields, especially in the area of environment. In this review, a comprehensive summary of the development of PDI-based materials in fluorescence detection and advanced oxidation technology for environment was introduced. Firstly, we chiefly presented the recent progress about the synthesis of PDI and PDI-based nanomaterials. Then, their application in fluorescence detection for environment was presented and categorized, principally including the detection of heavy metal ions, harmful anions and organic contaminants in the environment. In addition, the application of PDI and PDI-based materials in different advanced oxidation technologies for environment, such as photocatalysis, photoelectrocatalysis, Fenton and Fenton-like reaction and persulfate activation, was also summarized. At last, the challenges and future prospects of PDI-based materials in environmental applications were discussed. This review focuses on presenting the practical applications of PDI and PDI-based materials as fluorescent probes or catalysts (especially photocatalysts) in the detection of hazardous substances or catalytic elimination of organic contaminants. The contents are aimed at supplying the researchers with a deeper understanding of PDI and PDI-based materials and encouraging their further development in environmental applications.

Recent Advances in Perylene Diimide-Based Active Materials in Electrical Mode Gas Sensing

This review provides an update on advances in the area of electrical mode sensors using organic small molecule n-type semiconductors based on perylene. Among small organic molecules, perylene diimides (PDIs) are an important class of materials due to their outstanding thermal, chemical, electronic, and optical properties, all of which make them promising candidates for a wide range of organic electronic devices including sensors, organic solar cells, organic field-effect transistors, and organic light-emitting diodes. This is mainly due to their electron-withdrawing nature and significant charge transfer properties. Perylene-based sensors of this type show high sensing performance towards various analytes, particularly reducing gases like ammonia and hydrazine, but there are several issues that need to be addressed including the selectivity towards a specific gas, the effect of relative humidity, and operating temperature. In this review, we focus on the strategies and design principles applied to the gas-sensing performance of PDI-based devices, including resistive sensors, amperometric sensors, and operating at room temperature. The device properties and sensing mechanisms for different analytes, focusing on hydrazine and ammonia, are studied in detail, and some future research perspectives are discussed for this promising field. We hope the discussed results and examples inspire new forms of molecular engineering and begin to open opportunities for other rylene diimide classes to be applied as active materials.

A xanthene-based novel colorimetric and fluorometric chemosensor for the detection of hydrazine and its application in the bio-imaging of live cells

An efficient xanthene-based colorimetric and fluorometric probe (MXI) for the selective detection of hydrazine in solution and in living cells.

Highly sensitive electrochemiluminescence aptasensor based on dual-signal amplification strategy for kanamycin detection

In order to effectively monitor the residue of kanamycin (KAN), a dual-signal-amplified electrochemiluminescence (ECL) aptasensor based on multi-walled carbon nanotubes@titanium dioxide/thionine (MWCNTs@TiO₂/Thi) was proposed. MWCNTs@TiO₂ with large specific surface area and favorable biocompatibility could accelerate charge transfer and enable high loading of luminol to enhance ECL response. As a perfect electronic mediator, Thi could also accelerate electron conductivity to further enhance ECL intensity. The ECL intensity of MWCNTs@TiO₂/Thi was enhanced for 3.6-fold compared with that of individual Thi because Thi could strongly interact with MWCNTs through π-π stacking force to enhance the electronic transmission. With the outstanding electron transfer property of MWCNTs@TiO₂ and Thi, ECL intensity of the proposed aptasensor was obviously increased. Upon addition of KAN, the aptamer bound to its target, which caused that the ECL intensity decrease significantly. Therefore, KAN concentration could be monitored on the basis of signal intensity. Under optimal conditions, the constructed aptasensor exhibited a sensitive response towards KAN and a low detection limit of 0.049 ng mL^-1 was obtained. It also possessed the excellent specificity, favorable stability and good reproducibility. Importantly, the application of proposed ECL aptasensor provides an efficient approach for highly sensitive detection of various small molecular contaminants.

Effect of Intercalants inside Birnessite-Type Manganese Oxide Nanosheets for Sensor Applications

Hydrazine is a common reducing agent widely used in many industrial and chemical applications; however, its high toxicity causes severe human diseases even at low concentrations. To detect traces of hydrazine released into the environment, a robust sensor with high sensitivity and accuracy is required. An electrochemical sensor is favored for hydrazine detection owing to its ability to detect a small amount of hydrazine without derivatization. Here, we have investigated the electrocatalytic activity of layered birnessite manganese oxides (MnO₂) with different intercalants (Li⁺, Na⁺, and K⁺) as the sensor for hydrazine detection. The birnessite MnO₂ with Li⁺ as an intercalant (Li-Bir) displays a lower oxidation peak potential, indicating a catalytic activity higher than the activities of others. The standard heterogeneous electron transfer rate constant of hydrazine oxidation at the Li-Bir electrode is 1.09- and 1.17-fold faster than those at the Na-Bir and K-Bir electrodes, respectively. In addition, the number of electron transfers increases in the following order: K-Bir (0.11 mol) < Na-Bir (0.17 mol) < Li-Bir (0.55 mol). On the basis of the density functional theory calculation, the Li-Bir sensor can strongly stabilize the hydrazine molecule with a large adsorption energy (-0.92 eV), leading to high electrocatalytic activity. Li-Bir also shows the best hydrazine detection performance with the lowest limit of detection of 129 nM at a signal-to-noise ratio of ∼3 and a linear range of 0.007-10 mM at a finely tuned rotation speed of 2000 rpm. Additionally, the Li-Bir sensor exhibits excellent sensitivity, which can be used to detect traces of hydrazine without any effect of interference at high concentrations and in real aqueous-based samples, demonstrating its practical sensing applications.

Iron-Doped Titanium Dioxide Nanoparticles As Potential Scaffold for Hydrazine Chemical Sensor Applications

Herein, we report the fabrication of a modified glassy carbon electrode (GCE) with high-performance hydrazine sensor based on Fe-doped TiO2 nanoparticles prepared via a facile and low-cost hydrothermal method. The structural morphology, crystalline, crystallite size, vibrational and scattering properties were examined through different characterization techniques, including FESEM, XRD, FTIR, UV–Vis, Raman and photoluminescence spectroscopy. FESEM analysis revealed the high-density synthesis of Fe-doped TiO2 nanoparticles with the average diameter of 25 ± 5 nm. The average crystallite size of the synthesized nanoparticles was found to be around 14 nm. As-fabricated hydrazine chemical sensors exhibited 1.44 μA µM−1 cm−2 and 0.236 µM sensitivity and limit of detection (LOD), respectively. Linear dynamic ranged from 0.2 to 30 µM concentrations. Furthermore, the Fe-doped TiO2 modified GCE showed a negligible inference behavior towards ascorbic acid, uric acid, glucose, SO42−, NO3−, Pb2+ and Ca2+ ions on the hydrazine sensing performance. Thus, Fe-doped TiO2 modified GCE can be efficiently used as an economical, easy to fabricate and selective sensing of hydrazine and its derivatives.

Rational design of a novel turn-on fluorescent probe for the detection and bioimaging of hydrazine with barbituric acid as a recognition group

A novel turn-on fluorescent probe with barbituric acid as a unique recognition group has been rationally designed and synthesized using a facile method for detecting hydrazine.

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.

Electrosynthesis of carbon aerogel-modified AuNPs@quercetin via an environmentally benign method for hydrazine (HZ) and hydroxylamine (HA) detection

An ultrasensitive electrochemical sensor fabricated using a hydrothermal and environmentally benign methods for the detection of environmental pollutions, namely, hydrazine (HZ) and hydroxylamine (HA) has been described.

A dual-excitation fluorescent probe EuIII-dtpa-bis(HBT) for hydrazine detection in aqueous solutions and living cells

The Eu^III-dtpa-bis(HBT) dual-excitation fluorescence probe has good selectivity and strong anti-interference ability for the detection of N₂H₄.

In situ generated chromophore as the indicator for background-free sensing strategy of hydrazine with high sensitivity with in vitro and in vivo applications

A background-free sensing assay for hydrazine was developed by using a fluorescent chromophore generated in situ as the signal indicator.

Ultrarapid and Deep Debromination of Tetrabromodiphenyl Ether over Noble-Metal-Free Cu/TiO2 Nanocomposites under Mild Conditions

Fast and deep debromination of polybrominated diphenyl ethers (PBDEs) under mild conditions is a challenge in the field of pollution control. A strategy was developed to achieve it by exploiting Cu/TiO₂ composites as a noble-metal-free catalyst. Toward the debromination of 2,2',4,4'-tetrabromodiphenyl ether (BDE47) as a typical PBDE, the use of Cu/TiO₂ as a catalyst and hydrazine hydrate (N₂H₄·H₂O) as a reducing agent yielded a degradation removal of 100% and a debromination efficiency of 87.7% in 3 s. A complete debromination of BDE47 at 1500 mg L^-1 was possible by successively adding N₂H₄·H₂O. A debromination pathway involving active H atom species was proposed for the catalytic transfer hydrogenation (CTH) of PBDEs according to the identified degradation intermediates. A mechanism was further clarified by density functional theory calculations: electrons are delivered from N₂H₄·H₂O to the metallic Cu atom via a coordination of N in N₂H₄·H₂O with Cu atoms. The electron-trapped Cu atom interacts with adsorbed BDE47 to form a transition complex, and then the debromination of this complex occurs on the surface of Cu nanoparticles due to the hydrogen donation of N₂H₄·H₂O through the CTH process. The new method provides a highly efficient method to remove brominated pollutants.

Three-dimensional porous self-assembled chestnut-like nickel-cobalt oxide structure as an electrochemical sensor for sensitive detection of hydrazine in water samples

Three-dimensional NiCo₂O₄ is a kind of superior sensing material owing to its high electron transfer capability, large available surface area and numbers of active sites. In this work, NiCo₂O₄ of the three-dimensional chestnut-like structure were easily achieved through a one step hydrothermal process. Afterwards, the morphology and structure were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Based on the three-dimensional porous chestnut-like NiCo₂O₄, an electrochemical sensor for hydrazine (N₂H₄) detection is fabricated. This electrochemical platform can realize good selectivity, excellent stability, high sensitivity (∼2154.4 μA mM^-1 cm^-2), and low detection limit (0.3 μM), as well as a wide linear range from 1 μM to 1096 μM. The synergistic effect of nickel-cobalt in such mixed transition metal oxides which Co in Co₃O₄ is partially replaced by Ni are beneficial for enhancing sensing properties. This study proves that three-dimensional porous chestnut-like NiCo₂O₄ is electrochemically active for catalytic performance which is particular and promising material for good application in the practical detection of N₂H₄.

Ruthenium Nanoparticles Decorated Tungsten Oxide as a Bifunctional Catalyst for Electrocatalytic and Catalytic Applications

The syntheses of highly stable ruthenium nanoparticles supported on tungsten oxides (Ru-WO₃) bifunctional nanocomposites by means of a facial microwave-assisted route are reported. The physicochemical properties of these Ru-WO₃ catalysts with varied Ru contents were characterized by a variety of analytical and spectroscopic methods such as XRD, SEM/TEM, EDX, XPS, N₂ physisorption, TGA, UV-vis, and FT-IR. The Ru-WO₃ nanocomposite catalysts so prepared were utilized for electrocatalytic of hydrazine (N₂H₄) and catalytic oxidation of diphenyl sulfide (DPS). The Ru-WO₃-modified electrodes were found to show extraordinary electrochemical performances for sensitive and selective detection of N₂H₄ with a desirable wide linear range of 0.7-709.2 μM and a detection limit and sensitivity of 0.3625 μM and 4.357 μA μM^-1 cm^-2, respectively, surpassing other modified electrodes. The modified GCEs were also found to have desirable selectivity, stability, and reproducibility as N₂H₄ sensors, even for analyses of real samples. This is ascribed to the well-dispersed metallic Ru NPs on the WO₃ support, as revealed by UV-vis and photoluminescence studies. Moreover, these Ru-WO₃ bifunctional catalysts were also found to exhibit excellent catalytic activities for oxidation of DPS in the presence of H₂O₂ oxidant with desirable sulfoxide yields.

Co3O4 nanoparticles/MWCNTs composites: a potential scaffold for hydrazine and glucose electrochemical detection

We report the successful formation of cobalt oxide (Co₃O₄) nanoparticles/multi-walled carbon nanotubes (Co₃O₄/MWCNTs) composites as efficient electrocatalytic materials for chemical sensing.

Electrochemical Tailoring of Fibrous Polyaniline and Electroless Decoration with Gold and Platinum Nanoparticles

Presented in this work is a facile and quick electrochemical method for controlling the morphology of thick polyaniline (PANi) films, without the use of templates. By stepping the polymerization potential from high voltages to a lower (or series of lower) voltage(s), we successfully controlled the morphology of the polymer, and fibrous structures, unique to each potential step, were achieved. In addition, the resultant film was tested electrochemically for its viability as an electrode material for flexible batteries and supercapacitors. Furthermore, the PANi film was decorated with gold and platinum nanoparticles via an electroless deposition process for possible electrocatalytic applications, whereby the oxidation of hydrazine at the composite was investigated.

A highly sensitive fluorescent probe for detection of hydrazine in gas and solution phases based on the Gabriel mechanism and its bioimaging

A new probe 2-benzo[1,2,5]thiadiazol-4-yl-isoindole-1,3-dione (BTI) based on the Gabriel reaction was developed for hydrazine which shows promising selectivity towards hydrazine over other analytes.

Copper nanoparticles decorated polyaniline–zeolite nanocomposite for the nanomolar simultaneous detection of hydrazine and phenylhydrazine

The high electrocatalytic activity of the CuNPs–PANI–Nano-ZSM-5 nanocomposite can be attributed to the synergistic contribution provided by the highly dispersed copper nanoparticles and conductive PANI film on high surface area Nano-ZSM-5.

AH, Taye N, Mogare DG, Chattopadhyay S, Das A. Specific receptor for hydrazine: mapping the in situ release of hydrazine in live cells and in an in vitro enzymatic assay

New chemodosimetric reagent for the specific detection of hydrazine in physiological conditions as well as for the mapping of its in situ generation in live Hct116 and HepG2 cells by enzymatic transformations.