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Oil spilled during transportation, domestic, and industrial usage causes grave water and soil pollution. Therefore, oil recovery through absorption or separation from water has been a challenge to the scientific community. The 3D porous structure of polyurethane (PU) sponge attracted significant attention in oil-water separation applications. However, its poor hydrophobicity decreases and limits its oil-absorption efficacy dramatically. In this paper, we focused on improving the hydrophobicity of the sponge by modifying it with graphene oxide (GO) followed by its reduction to reduce graphene oxide (rGO) via a commonly available green reducing agent, L-ascorbic acid (L-AA). The rGO modified PU sponge was used to absorb and collect oil from an oil-water mixture with satisfactory recoveries of up to ~ 97%. Moreover, the prepared rGO-PU sponge exhibited excellent reusability and compressibility without any crack or leaking. Finally, we compared the results of this study with rGO modified cotton (rGO-cotton) surfaces prepared via the same protocols. The results show that the high compressible and porous nature of sponges (rGO-PU) outperformed the rGO-cotton. Furthermore, this research work was proven to be environmentally friendly and cost-effective absorbent for efficiently extracting oil from oil-water mixtures with fewer toxic chemicals and cheap raw materials utilization. [ABSTRACT FROM AUTHOR]

The present study demonstrates the thermal stability and photocatalytic activity of TiO2-based nanotubes with respect to post-hydrothermal treatment. Titanate nanotubes were synthesized by adapting an alkali hydrothermal method from TiO2 sol using NaOH as a catalyst. The effect of post-hydrothermal heating on the properties—such as structure, morphology, textural properties, and activity—of as-synthesized one-dimensional titania nanostructure is investigated in detail. The characterizations are carried out using SEM, EDX, TEM, XRD, and a BET surface area analyzer. When heated in the presence of water in an autoclave, the protonated titanate phase of the nanotubes converts to anatase phase. Meanwhile, the tubular morphology is gradually lost as the post-hydrothermal heating duration increases. The photocatalytic activity was assessed utilizing the photo-oxidation of an amaranth dye. It is discerned that the as-prepared nanotubes are photocatalytically inactive but become active after post-hydrothermal processing. The activity trend follows the formation of the active phase—the titanate phase crystallizes into a photocatalytically-active anatase phase during post-hydrothermal heating. The effect of experimental parameters, such as reaction pH, dye concentration, and amount of catalyst, on the dye removal is studied. The findings also highlight that the role of holes/OH• is more prominent as compared to conduction band electron/O2−• for the removal of the dye. In addition, the photocatalyst exhibited excellent stability and reusability. [ABSTRACT FROM AUTHOR]

MXene, a novel class of 2-dimensional transition metal carbides has evolved as a promising material for various applications owing to its outstanding characteristics such as hydrophilicity, high electrical conductivity, surface area, and attractive topological structure. MXenes can form dispersion in common solvents and constitute composite with other nanomaterials, which can be utilized as effective transducers for molecular sensing. MXene-modified support materials, thus provide an intriguing platform for immobilization of target molecules onto their surface. The literature reveals that it has been increasingly utilized in the sensing of diverse types of analytes including glucose, pharmaceuticals, metals and dyes, cancer markers, pesticides, neurotransmitters, small valuable molecules, and so on. In this review, we summarize the recent updates in the MXene modified materials for sensing. For the convenience of our audience, we have distributed the analytes into categories and discussed them comprehensively. Not only we present the synthesis approach, electrochemical properties and surface chemistry of MXenes but also discussed briefly the current challenges and an outlook for future research in the related area. [ABSTRACT FROM AUTHOR]

Microbial contaminations and infections are hazardous and pose crucial concerns for humans. They result in severe morbidity and mortality around the globe. Even though dish-culturing, polymerase chain reaction (PCR), an enzyme-linked immunosorbent assay (ELISA) exhibits accurate and reliable detection of bacteria but these methods are time-consuming, laborious, and expensive. This warrants early detection and quantification of bacteria for timely diagnosis and treatment. Bacteria imprinting ensures a solution for selective and early detection of bacteria by snagging them inside their imprinted cavities. This review provides an insight into MIPs based bacterial detection strategies, challenges, and future perspectives. [ABSTRACT FROM AUTHOR]

In this work, a simple and facile method was developed to achieve controlled oxidation and enhance the surface area of MXene nanosheets and their utilization in the efficient sensing of ascorbic acid (AA or vitamin C). After etching of MAX phase to MXene via the MILD technique, controlled flash oxidation was carried out in the open air environment for 1.5 h, followed by flocculation of oxidized MXene nanosheets by using H 2 SO 4 , consequently achieving crumpled MXene possessing anatase phase, porosity, and improved surface area as revealed and confirmed by SEM, TEM, Raman, and BET analysis results. The as-prepared crumpled MXene was coated over a glassy carbon electrode (GCE) and used to determine AA successfully via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) with a linear concentration range of 300 μM to 0.005 μM with a detection limit (LOD) of 2 nM (2.8 % RSD and S/N = 3). The developed electrochemical sensor was used to determine the AA in various actual samples such as juice, urine, serum, and erythrocytes spiked with AA with excellent recoveries in the 94–103 % range. The sensor also demonstrated excellent reproducibility (~1 % RSD for five repetitive assays) and a shelf life of nearly one month with a negligible decrease in response. Furthermore, it lost only 10 % of its response for the next ten days. It also showed satisfactory selectivity toward AA in the presence of other similar compounds, including uric acid (UA), dopamine (DA), and glucose. [ABSTRACT FROM AUTHOR]

Cancer has been responsible for high morbidity and mortality globally. The treatment of cancer is possible using different kinds of therapies using anticancer drugs if it is diagnosed at the right time. Nevertheless, their appropriate administration for maximum therapeutic effect and their elimination from the patient's body causing environmental problems are two big issues which could be successfully abated using molecular imprinted polymers (MIPs) owing to their unique features. In this review, we have compiled and discussed the works on the determination and controlled release of anticancer drugs based on MIPs. We also highlighted the current challenges and remedies, and the future direction of MIPs in this area. [ABSTRACT FROM AUTHOR]

Apart from being a vital catecholamine molecule responsible for the proper functioning of central nervous system (CNS), hormonal and renal systems, dopamine (DA) has also been increasingly employed as a functional monomer in the fabrication of surface molecular imprinting of valuable analytes, especially for proteins. The application of dopamine as functional monomer was inspired from mussel adhesion protein, its capability of self‐polymerization under weak alkaline aqueous solution resulting into thin biocompatible highly cross‐linked polydopmaine (PDA) film and cost‐effectiveness. Furthermore, it could adhere strongly on various (organic and inorganic) substrates without any attachment, and possesses plenty of noncovalent functionalities such as amino‐containing groups, hydroxyl‐containing groups and π‐π for further modifications. In this first ever review, we focused our attention on the utilization and influence of DA as a functional monomer in the fabrication of molecular imprinting and discussed it comprehensively. [ABSTRACT FROM AUTHOR]

Apart from being a vital catecholamine molecule responsible for the proper functioning of the central nervous system (CNS), hormonal and renal systems, dopamine (DA) has also been increasingly employed as a functional monomer in the fabrication of surface molecular imprinting polymers (MIPs) for valuable analytes. Herein, we demonstrate the effective imprinting of 6-thioguanine (6-TG), an anticancer drug, via mussel-inspired self-polymerization of dopamine conducted in a weakly alkaline solution over reduced graphene oxide (rGO). The polymerization of 6-TG resulted into a thin polydopamine (PDA) film of 8.4 nm thickness. Removal of 6-TG molecules from this imprinted PDA film created numerous cavities of 6-TG. The electrochemical investigation of MIP electrodes found an excellent electrocatalytic activity toward 6-TG with a significant decrease in the over-potential as compared to that of the bare glassy carbon electrode (GCE). This can be attributed to the graphene's distinct physical and chemical features such as subtle electronic characteristics, an attractive π–π interaction as well as the strong adsorptive capability of MIP films. This electrochemical sensor displayed a high selectivity owing to the specific imprinted cavities for adrenaline and worked well over a wide linear concentration range of adrenaline between 0.0015 and 50 μM with a detection limit (LOD) of 0.25 nM and good reproducibility and stability. Our system depicts excellent recoveries from 97.0% to 100.6% for two different samples of urine and thioguanine drugs. These results show the great potential of our system with multiple advantages, including convenient fabrication and optimization, high sensitivity and selectivity, high reproducibility and stability, and cost-effectiveness. [ABSTRACT FROM AUTHOR]

MXenes, 2-dimensional (2D) layered materials, have been able to garner immense popularity among researchers and academia alike in recent times. MXenes are typically produced from the selective etching of "A" group metal layer using an etchant (usually HF) from the parent MAX phase structure where M represents a metal from early transition metals. Their unique surface chemistry and intriguing electrochemical behavior, combined with their high biocompatibility, make them ideal as a support matrix for the development of cutting-edge electrochemical energy storage, biomedicine, electrochemical sensing, and biosensing devices. Due to the surging demand for batteries that can enable recent technological advancements such as electric vehicles to reach their full potential, the high specific capacitance and outstanding electrochemical energy storage of MXenes are under extensive research in recent times. Ti-based MXene has shown tremendous potential and thus many excellent reviews appeared around it and other MXenes in general. However, there are not many specialized reviews for other types of MXenes. Herein, we reviewed the current research advances, challenges, and prospects of the three most popular MXenes: Niobium (Nb), Vanadium (V), and Molybdenum (Mo) based MXenes. The applications of each form of MXene have been divided into categories for the reader's convenience. Finally, we have highlighted the challenges and future perspectives. [ABSTRACT FROM AUTHOR]

Dopamine (DA) is a valuable neurotransmitter of enormous biological significance and it is widely distributed in the mammalian central nervous system (CNS). DA has been known to play a critical role in the functioning of central nervous system (CNS), renal, and hormonal systems. It has been discovered that the lack of DA is associated with many clinical conditions including debilitating ailment, Schizophrenia, and Parkinson's disease. Many reliable methods have been reported for the accurate determination of DA, however, interferences from co-existing molecules such as ascorbic acid (AA), and Uric acid (UA) are inevitable. To overcome it, molecular imprinted polymer (MIP) is considered one of the best strategy owing to its pre-determined selectivity for an imprinted template. A considerable amount of research has been done on MIP based approach for DA determination. Furthermore, various types of ways including the utilization of conducting monomers, graphene, carbon nanotubes (CNTs), gold nanoparticles (AuNPs), and so on have been incorporated to enhance the signal response. In this review, we have not included the vast literature available for dopamine, instead, we have summarized the recent developments of MIP based strategies for the determination of DA using articles encompassing 2010 to till now as well as outlined the current challenges and developmental needs of MIP strategies. [ABSTRACT FROM AUTHOR]

Generally, the toxic and mutagenic functional monomers are employed to synthesize the MIP films. This work demonstrates the fabrication of molecular imprinted polymer (MIP) based electrochemical sensor for adrenaline using a green functional monomer, nicotinamide. The adrenaline imprinted film was electropolymerized over reduced graphene oxide (rGO) modified glassy carbon electrode (GCE) by cyclic voltammetry (CV). The as-synthesized sensors were characterized by SEM. The electrochemical analysis showed that the graphene-modified electrode exhibited excellent electrocatalytic activity toward adrenaline and the over-potential of adrenaline decreased significantly as compared to bare GCE which can be attributed to graphene's unique physical and chemical properties such as subtle electronic characteristics, attractive π–π interaction, and strong adsorptive capability of MIP film. The thickness of MIP was estimated to be 1.97 nm by coulometric analysis. This electrochemical sensor displays high selectivity owing to specific imprinted cavities for adrenaline and worked well over a wide linear concertation range of adrenaline between 0.015 μM and 40 μM with a detection limit (LOD) of 3 nM. The sensor offered good reproducibility (Relative standard deviation of 3.44%) and retained 94.6% of its initial response for over 40 days. Finally, excellent recoveries from 96.0% to 100.7% were obtained for two different samples of urine and adrenaline ampoules. Thus, this work holds great promise with numerous advantages including easy fabrication, high sensitivity and selectivity, high throughput and satisfactory reproducibility for adrenaline. [ABSTRACT FROM AUTHOR]

This work demonstrates the facile and efficient preparation protocol of β-Cyclodextrin-reduced graphene oxide modified glassy carbon electrode (β-CD/RGO/GCE) sensor for an impressive chiral selectivity analysis for phenylalanine enantiomers. In this work, the immobilization of β-CD over graphene sheets allows the excellent enantiomer recognition due to the large surface area and high conductivity of graphene sheets and extraordinary supramolecular (host-guest interaction) property of β-CD. The proposed sensor was well characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and electrochemical impedance spectroscopy (EIS) techniques. The analytical studies demonstrated that the β-CD/RGO/GCE exhibit superior chiral recognition toward L -phenylalanine as compared to D -phenylalanine. Under optimum conditions, the developed sensor displayed a good linear range from 0.4 to 40 µM with the limit of detection (LOD) values of 0.10 µM and 0.15 µM for l - and D -phenylalanine, respectively. Furthermore, the proposed sensor exhibits good stability and regeneration capacity. Thus, the as-synthesized material can be exploited for electrochemical enantiomer recognition successfully. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate a sulfur-doped reduced graphene oxide (SrGO) product fabricated using an eco-friendly biomass precursor “lenthionine” through a high temperature doping process. The product is used for making a highly sensitive electrochemical sensor for detection of 8-hydroxy-2′-deoxyguanosine (8-OHdG) molecule, which is an important biomarker for oxidative stress, cardiovascular diseases, and cancers. The sulfur-doping amount was regulated and a maximum sulfur content of 2.28 atom% was achieved through controlling the precursor amount. Homogenous presence of large number of sulfur atoms in SrGO in the form of thiophenic ( C S C ) bond produced robust sensitivity (∼1 nM), very wide detection window (20–0.002 μM), good selectivity, high stability and reproducibility, and excellent recoveries for the detection of 8-OHdG biomarker in optimized experimental conditions. The excellent electrochemical sensitivity of SrGO sensor is attributed to the strong electron-donating ability of sulfur that facilitates the electron transfer to the biomolecules in the electrochemical reactions. Thus, the proposed method endorses an excellent platform for the electrochemical detection of 8-OHdG with great ease and reliability. [ABSTRACT FROM AUTHOR]

This review is aimed to discuss the molecular imprinted polymer (MIP)-based drug delivery systems (DDS). Molecular imprinted polymers have proved to possess the potential and also as a suitable material in several areas over a long period of time. However, only recently it has been employed for pharmaceuticals and biomedical applications, particularly as drug delivery vehicles due to properties including selective recognition generated from imprinting the desired analyte, favorable in harsh experimental conditions, and feedback-controlled recognitive drug release. Hence, this review will discuss their synthesis, the reason they are selected as drug delivery vehicles and for their applications in several drug administration routes (i.e. transdermal, ocular and gastrointestinal or stimuli-reactive routes). [ABSTRACT FROM AUTHOR]

Diabetes is a major health problem causing 4 million deaths each year and 171 million people suffering worldwide. Although there is no cure for diabetes, nevertheless, the blood glucose level of diabetic patients should be monitored tightly to avoid further complications. Thus, monitoring of glucose in blood has become an inevitable need leading to fabrication of accurate and sensitive advanced blood sugar detection devices for clinical diagnosis and personal care. It led to the development of enzymatic glucose sensing approach. Later on, various types of nanostructures have been utilized owing to their high surface area, great stability, and cost effectiveness for the fabrication of enzymatic as well as for nonenzymatic glucose sensing approach. This work reviews on both categories, however it is not intended to discuss all the research reports published regarding nanostructure based enzymatic and nonenzymatic approaches between mid-2010 and mid-2015. We, do, however, focused to describe the details of many substantial articles explaining the design of sensors, and utilities of the prepared sensors, so that readers might get the principles behind such devices and relevant detection strategies. This work also focuses on biocompatibility and toxicity of nanomaterials as well as provides a critical opinion and discussions about misconceptions in glucose sensors. [ABSTRACT FROM AUTHOR]

Abstract: A simple and highly sensitive method for simultaneous detection of anticancer drugs is developed by integrating the preconcentration and separation steps in a microfluidic device with an amperometric biosensor. An amperometric detection with dsDNA and cardiolipin modified screen printed electrodes are used for the detection of anticancer drugs at the end of separation channel. The preconcentration capacity is enhanced thoroughly using field amplified sample stacking and field amplified sample injection techniques. The experimental parameters affecting the analytical performances, such as pH, temperature, buffer concentration, water plug length, and detection potential are optimized. A reproducible response is observed during multiple injections of samples with a RSD <5%. The calibration plots are linear with the correlation coefficient between 0.9913 and 0.9982 over the range of 2–60 pM. The detection limits of four drugs are determined to be between 1.2 (±0.05) and 5.5 (±0.3) fM. The applicability of the device to the direct analysis of anticancer drugs is successfully demonstrated in a real spiked urine sample. Device was also examined for interference effect of common chemicals present in real samples. [Copyright &y& Elsevier]

Abstract: Some open tubular (OT) molecule imprinted polymer (MIP) silica capillary columns have been prepared using atenolol, sulpiride, methyl benzylamine (MBA) and (1-naphthyl)-ethylamine (NEA) as templates by the pre-established generalized preparation protocol. The four MIP thin layers of different templates showed quite different morphologies. The racemic selectivity of each MIP column for the template enantiomers was optimized by changing eluent composition and pH. The template structural effects on chiral separation performance have been examined. This work verifies the versatility of the generalized preparation protocol for OT-MIP silica capillary columns by extending its boundary toward templates with basic functional group moieties. This study is the very first report to demonstrate a generalized MIP preparation protocol that is valid for both acidic and basic templates. The chiral separation performances of atenolol and sulpiride by the MIPs of this study were found better than or comparable to those of atenolol and sulpiride obtained by non-MIP separation techniques and those of some basic template enantiomers obtained by MIP based techniques. [Copyright &y& Elsevier]

Abstract: Enhanced chiral separation performance has been observed for ketoprofen enantiomers in capillary electrochromatography (CEC) with an open-tubular (OT) column prepared with a specific molecule imprinted polymer (MIP) on the innerwall of 50μm ID capillary. The column was prepared by in situ thermal polymerization inside the pretreated and silanized fused silica capillary. A specific diluted monomer mixture composed of S-ketoprofen, methacrylic acid (MAA, functional monomer), ethylene glycol dimethacrylate (EDMA, cross-linker), and 4-styrenesulfonic acid (4-SSA) dissolved in 9/1 (v/v) acetonitrile/2-propanol was used to fabricate the OT-MIP layer. 4-SSA was added to form a MIP layer capable of stable and strong electro-osmotic flow (EOF) over the pH range of this study securing CEC elution of ketoprofen having partial negative charge near the optimized pH. Various parameters such as buffer pH, organic modifier composition, salt concentration, and applied potential have been optimized for CEC chiral separation of ketoprofen enantiomers. Very good separation selectivity and efficiency were observed, thus the chromatographic resolution of ketoprofen enantiomers was as high as 10.5, and the number of theoretical plates of R-ketoprofen, 156,000/m (40,000/m for S-ketoprofen), which proves that the OT-MIP-CEC type approach is a promising strategy in MIP study. [Copyright &y& Elsevier]

Cancer is the one of the fatal and dreaded disease responsible for huge number of morbidity and mortality across the globe. It is expected that the global burden will increase to 21.7 million fresh cancer cases as compared to present estimate of 18.1 million cancer cases in addition to nearly 9.6 million cancer deaths worldwide. In response to cancerous or certain benign conditions; specific type of tumor or cancer markers (biomarkers) are produced at much higher levels which are secreted into the urine, blood, stool, tumor or other tissues. Therefore, the efficient and early detection of cancer biomarkers is necessary which can offer a reliable way for cancer patient screening and diagnosis. This process not only helps in the evaluation of pathogenic processes but also the prognosis of different cancers and pharmacological responses to therapeutic interventions are secured. Over the past several years, electrochemical detection methods have proved to be the most attractive methods among many, due to the advantages, such as simple instrumentation, portability, low cost and high sensitivity. Furthermore, the modifications of these electrochemical immunosensors by utilizing various types of nanomaterials enable these systems to detect trace amount of target tumor markers. Hence, herein, we intend to review the selective works on electrochemical detection of various biomarkers using wide range of nanomaterials with a particular focus on graphene. Image 1 • Cancer is responsible for huge number of morbidity and mortality. • Early detection of cancer biomarkers is necessary for cancer patient screening and diagnosis. • Nanomaterials based electrochemical sensors offer simple instrumentation, portability, low cost and high sensitivity. • Particulalry, graphene based elctrochemical sensors are able to detect extremely low amount of target tumor markers. • The current challenges and the outlook of these electrochemical sensors are highlighted. [ABSTRACT FROM AUTHOR]

Herein, we propose a facile chemical reduction method to synthesize the molybdenum carbide (Mo 2 C) nanoparticles and its application for the electrochemical detection of folic acid (FA) through imprinting technique. Raman scattering, photoelectron spectroscopy and electron microscopy techniques were employed to study the properties of Mo 2 C nanoparticles. FA imprinting was carried out in the presence of pyrrole monomer over Mo 2 C modified glassy carbon electrode (GCE). The proposed sensor showed the detection behavior for wide range of FA concentrations from 0.01 μM to 120 μM with an excellent LOD value of 4 nM and good selectivity toward FA as compared to other co-existing species in real samples. The fabricated MIP-Mo 2 C/GCE sensors were able to be replicated with ∼1.9% RSD, and their reproduced sensor offered good repeatability (RSD; 1.6%) and stability. • A facile chemical reduction method employed to synthesis the Mo 2 C. • MIP-Mo 2 C/GCE sensor electrode successfully fabricated by electropolymerization. • MIP-Mo 2 C/GCE sensor showed the superior sensitivity performance than NIP–Mo 2 C/GCE. • High reproducibility and stability revealed with an excellent LOD value of 4 nM. [ABSTRACT FROM AUTHOR]

AbstractMolecularly imprinted polymer (MIP)-based electrochemical sensors have been extensively researched due to their higher sensitivity, quick response, and operational ease. To develop more advanced sensing devices with enhanced properties, MIPs have been integrated with two-dimensional (2D) layered materials such as transition metal dichalcogenides (TMDs) and MXenes. These 2D materials have unique electronic properties and an extended surface area, making them promising sensing materials that can improve the performance of MIPs. In this review article, we describe the methods used for the synthesis of TMDs and MXenes integrated MIP-based electrochemical sensors. Furthermore, we have provided a critical review of a wide range of analytes determined through the application of these electrochemical sensors. We also go over the influence of TMDs and MXenes on the binding kinetics and adsorption capacity which has enhanced binding recognition and sensing abilities. The combination of TMDs and MXenes with MIPs shows promising synergy in the development of highly efficient recognition materials. In the future, these sensors could be explored for a wider range of applications in environmental remediation, drug delivery, energy storage, and more. Finally, we address the challenges and future perspectives of using TMDs and MXenes integrated MIPs. We conclude with a focus on future development and the scope of integrating these materials in sensing technology. [ABSTRACT FROM AUTHOR]

Developing high-performing and scalable electrode materials for supercapacitors and batteries has been of tremendous interest for the world's forthcoming clean and renewable energy transition. As a versatile material, Two-dimensional graphitic carbon nitride (g-CN) has been utilized in electrochemical energy storage (EES) applications due to its nitrogen-rich adsorption sites, cost-effective production, and tunable electronic structure. The electrochemical performance of pristine g-CN has been boosted by forming hybrid architectures with highly conductive carbon-based materials, such as graphene, reduced graphene oxide, carbon nanofibers, carbon nanotubes, and beyond (e.g., MXene). Using such heterogeneous compositions for EES applications has significantly increased in recent years. This study reviews the g-CN/carbon nanomaterial (CNM) hybrids, considering the dimensionality in nanomaterials, and underscores the influence of the material's dimensionality and the synthesis/fabrication routes. The effect of structural and physicochemical changes on the electrode's electrochemical performance after hybridization is presented comparatively. Besides, the comprehensive review outlines challenges and future improvements in g-CN/CNM hybrid materials for outstanding developments in energy storage systems. [Display omitted] • Graphitic carbon nitride (g-CN)/carbon nanomaterial (CNM) hybrids are reviewed for supercapacitor and battery applications. • The impact of the CNM-type on the hybrid electrode's performance is examined through a chemical and physical perspective. • An overview of how hybrid electrode synthesis affects ion/electron transport, surface area, and porosity is provided. • Design-oriented control of the physicochemical properties for enhanced electrochemical performance is exemplified. • g-CN/CNM nanoarchitectures are emphasized as electrode materials with the potential for easy scalability. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize highly reactive ZrO 2 nanoparticles using a straightforward sol-gel method for addressing water contamination from hazardous metal ions and organic dyes. Structural and photocatalytic properties were assessed using X-ray diffraction (XRD), Fourier transmission Infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), and UV–visible absorption spectroscopy. XRD analysis confirmed the tetragonal crystal structure of ZrO 2. Photodegradation experiments using Eriochrome Black T (EBT) as a model dye revealed nearly 99% degradation under natural sunlight. Investigations into catalyst loading, dye concentration, pH, and irradiation source were conducted. Preliminary tests demonstrated the adsorbent's efficacy in removing Ca2+ ions. Further process optimizations could significantly enhance the potential of this innovative adsorbent for extracting metal ions from complex effluents. • Investigating the degradation of dyes in wastewater through photodegradation studies. • Tunning the morphology of nanocomposites to tackle difficult dye degradation scenarios. • Exploration of creating, analyzing, and potential uses of ZrO 2 nanoparticles. • Efficient elimination of heavy metal ion pollutants. [ABSTRACT FROM AUTHOR]

Abstract: We report here the fabrication of a robust, highly sensitive, reliable and reproducible phenyl hydrazine chemical sensor using Ag-doped ZnO nanoflowers as efficient electron mediators. The Ag-doped ZnO nanoflowers were synthesized by facile hydrothermal process at low-temperature and characterized in detail in terms of their morphological, structural, compositional and optical properties. The detailed morphological and structural characterizations revealed that the synthesized nanostructures were flower-shaped, grown in very high-density, and possessed well-crystalline structure. The chemical composition confirmed the presence of Ag into the lattices of Ag-doped ZnO nanoflowers. High sensitivity of ∼557.108±0.012mAcm−2 (molL−1)−1 and detection limit of ∼5×10−9 molL−1 with correlation coefficient (R) of 0.97712 and short response time (10.0s) were observed for the fabricated chemical sensor towards the detection of phenyl hydrazine by using a simple current–voltage (I–V) technique. Due to high sensitivity and low-detection limit, it can be concluded that Ag-doped ZnO nanoflowers could be an effective candidate for the fabrication of phenyl hydrazine chemical sensors. [Copyright &y& Elsevier]

Abstract: This paper reports a very simple, reliable and facile methodology to fabricate ultra-high sensitive liquid ammonia chemical sensor using well-crystalline hexagonal-shaped ZnO nanopencils as an efficient electron mediator. A low-temperature facile hydrothermal technique was used to synthesize ZnO nanopencils. The synthesized nanopencils were characterized in detail in terms of their morphological, structural and optical properties which confirmed that the synthesized nanomaterial is well-crystalline, possessing wurtzite hexagonal phase and possess very good optical properties. A very high sensitivity of ∼26.58μAcm−2 mM−1 and detection limit of ∼5nM with a correlation coefficient (R) of 0.9965 and a response time of less than 10s were observed for the fabricated liquid ammonia by I–V technique. To the best of our knowledge, by comparing the literature, it is confirmed that the fabricated sensor based on ZnO nanopencils exhibits highest sensitivity and lowest detection limit for liquid ammonia. This research opens a way that simply synthesized nanomaterials could be used as efficient electron mediators for the fabrication of efficient liquid ammonia chemical sensors. [Copyright &y& Elsevier]

Despite their high analytical performance, conventional analytical biosensor devices are usually difficult to handle, time-consuming, bulky and expensive. As a result, their applications remain restricted to resource-limited environments. In particular, the transportation of conventional analytical equipment is challenging for the proper in-situ point of need (PON)/point of care (POC) detection of biomolecules. In this context, smartphones, the most widely utilized cutting-edge mobile gadgets, continue to be a favored option because of their ease of portability and revolutionary sensing capabilities. On the other hand, aptamers are molecular recognition units consisting of nucleic acids with highly sensitive and selective recognition capabilities towards their respective targets. The coupling of smartphones with aptamers have led the development of advanced, user-friendly, portable, and cost-effective in-situ PON/POC biosensors for the detection of biomolecules. Such sensors are well-suited for a variety of applications, including food safety, environmental monitoring, and disease diagnostics. Herein, for the first time, achievements made between 2017 and 2022 in the concept and design of the smartphone-enabled aptasensors for biosensing applications are reviewed. The review covers different fabrication strategies and the discussion of several operating systems, underlying programs, and related software. At the end, the important merits, challenges, and future prospects of smart phone-driven aptasensors are presented. This report intends to assist scientists and engineers in comprehending the fabrication of smartphone-based aptasensors and their underlying sensing principles, as well as stimulating the future developments in the direction of affordable, portable, simple, and readily available sensing devices. • The smartphone-based aptasensors facilitate advanced, user-friendly, portable, and cost-effective PON and POC biosensing. • Smartphone-enabled aptasensors are well-suited for applications in food safety, environmental monitoring, and disease diagnostics. • Fabrication strategies, working mechanisms, underlying operating systems, and related hardware/software have been reviewed. • Advantages, challenges and future outlook of smartphone-based aptasensors have been discussed. [ABSTRACT FROM AUTHOR]

Review: 168 refs. [ABSTRACT FROM AUTHOR]

Abstract: Magnesium hydroxide (Mg(OH)2) hexagonal nanodisks were synthesized via a facile microwave-assisted hydrothermal process and used, for the first time, as an efficient electron mediators for the fabrication of efficient ethanol chemical sensor. The synthesized hexagonal nanodisks were characterized in terms of their morphological and structural properties. The detailed morphological and structural investigations reveal that the synthesized Mg(OH)2 hexagonal nanodisks are grown in high density, and possessing hexagonal crystal structure. Using as-synthesized Mg(OH)2 hexagonal nanodisks, an efficient and robust ethanol chemical sensor has been fabricated which showed a very high and reproducible sensitivity of ∼6.89±0.01μAcm−2 mM−1 with a response time of less than 10s, linear dynamic range from 0.1μM to 10mM and a correlation coefficient of R =0.9957. The limit of detection (LOD) was estimated to be ∼73nM. This work demonstrates that the simply synthesized Mg(OH)2 nanostructures can effectively be used for the fabrication of efficient ethanol chemical sensors. [Copyright &y& Elsevier]