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Background Synthetic chemical pesticides play a significant role in increasing the overall yield and productivity of agricultural foods by controlling and eradicating pests, insects, and numerous plant-related diseases. The over-spraying of pesticides onto crops has escalated pesticide contamination of food products and water bodies, as well as disturbing ecological and environmental systems. In this regard, developing simple, low-cost, and rapid-sensing strategies and portable devices for the precise, efficient, rapid, and on-site detection of pesticide residues in agricultural fields is indeed necessary and urgently required for the wellbeing and safety of mankind and other species. Scope and approach In this review, we make a comprehensive study of the up-to-date state-of-the-art research progress on the on-site sensing strategies and portable devices for the detection of pesticide residues in agricultural foods using paper-, liquid-, and gel-based optical-sensing techniques. Moreover, we delineate the detailed on-site detection mechanism and sensing behavior of the aforementioned strategies and discuss the challenges and future perspectives associated with the development of optical techniques. Key findings and conclusions Recent scientific and technological studies on optical sensors such as fluorescence sensors, target-responsive hydrogels, chemiluminescence assay, tube enzyme-linked immunosorbent assay, enzymatic fiber-optic biosensor, phosphorescence, lateral flow immunoassay, double-signal fluorescence strategy, wearable glove-based sensors, and paper-based sensors have made novel advancements and brought scientific insight for the on-site detection of pesticide residues in agricultural foods. This review provides significant insights and future perspectives that might serve as the basis for the fabrication of novel optical sensors with applicability in various fields.

Purpose With its substantial CO2eq emissions, the agricultural sector is a significant greenhouse gas (GHG) emitter. Animal manure alone contributes 16% of the total agricultural emissions. With a rapidly increasing demand for animal-based protein, animal wastes are expected to rise if sustainable manure management practices are not implemented. Manures have the potential to be treated to generate valuable products (biofertiliser and biocrude) or feedstock for energy production. Thermochemical conversion technologies such as pyrolysis, combustion, supercritical gasification (SCWG), etc., have demonstrated their potential in manure management and valorisation. This study provides a broader overview of these technologies and envisages future manure valorisation trends. Methods The paper presents a state-of-the-art review of manure valorisation. Characterisation of manure, modelling and optimisation of thermochemical conversion technologies along with life cycle anaalysis (LCA) are also reviewed. Results The literature review highlighted that the thermochemical conversion technologies can generate bio-oils, syngas, H2, biofuels, heat, and biochar as carbon-free fertiliser. The reported calorific value of the produced bio-oil was in the range of 26 MJ/kg to 32 MJ/kg. However, thermochemical conversion technologies are yet to be commercialised. The major challenges associated with the scale-up of manure derived feedstocks are relatively high moisture and ash content, lower calorific value and higher concentration of impurities (N, Cl, and S). LCA studies conclude that gasification presents a sustainable option for manure valorisation as it is economical with modest environmental threats. Significance of Study This review briefly states the current challenges faced in manure management and presents the case for a sustainable valorisation of animal manures using thermochemical technologies. The economic, environmental and societal advantages of these technologies are presented in order to promote the scientific and industrial development of the subject in the academic and research community. Conclusions Thermochemical conversion technologies are promising for manure valorisation for energy and nutrient recovery. However, their commercialisation viability needs wide-ranging evaluations such as techno-economics, life-cycle analysis, technology take-up and identification of stakeholders. There should be clear-cut policies to support such technologies. It should be advocated amongst communities and industries, which necessitates marketing by the governments to secure a clean energy future for the planet. Graphical Abstract

The beguiling world of functional polymers is dominated by thermoresponsive polymers with unique structural and molecular attributes. Limited work has been reported on the protein-induced conformat...

Traditional laboratory-based sensing strategies for food contaminant detection are often limited because they are time-consuming and expensive and require trained personnel, which makes them unsuitable for routine sensing. Therefore, the scientific and industrial community is showing enormous interest in the design and development of portable sensing devices for the on-site and point-of-care detection of food contaminants. Portability is one of the chief characteristic features of designing contemporary analytical devices. Portable devices have received tremendous attention, as these novel devices have advanced the field of sensing. Various sensing strategies have been utilized for on-site detection of food contaminants. Among these, portable electrochemical devices have emerged vigorously in the past few years. Scientists and industrialists have worked effortlessly to develop portable electrochemical devices for a minute amount of food contaminant detection in water bodies and food products. The current work aims to demonstrate recent research progress related to the design, development, and improvement of portable electrochemical devices for detection of food contaminants.

Dry plasma reduction under atmospheric pressure is a unique approach for stably, continuously, easily, and uniformly fabricating Ag layer on the metal seeds-polyethylene terephthalate (PET) substrate. In this study, effects of particle size, surface uniformity, surface coverage, and film thickness of metal seeds such as Ag, Cu, Fe and Ni on the formation of uniform Ag layer were studied on the basis of their surface free energies and critical radius, which further leads to variations in the sheet resistance levels of the silver layers. The root mean square roughness and sheet resistance of the Ag layer PET substrate were decreased with the deposition of metal seeds. Among the added seed metals, Ni seed has shown best uniformity. Furthermore, the fabricated films were applied for electromagnetic interference (EMI) shielding. Among the added seed metals, Ni has shown the highest electromagnetic interference shielding effectiveness. The present study will be useful for the development of various low-cost metal films in the field of EMI shielding.

Thermoresponsive polymers (TRPs) that undergo significant conformation/aggregation changes in response to changes in temperature have extensive range of potential applications in various fields of science and technology. Among different types of TRPs, poly (N-isopropylacrylamide) (PNIPAM) is a suitable amphiphilic polymer for studying the conformational changes due to its biocompatible behavior with various additives. In order to get deeper insights of the TRPs in the presence of additives, we examined the collapse and aggregation of thermoresponsive polymer (PNIPAM) in aqueous solution containing variable amounts of 1-allyl-3-methylimidazolium bromide ([Amim][Br]). The influence of ionic liquid on the lower critical solution temperature (LCST) of PNIPAM aqueous solution were examined with the aid of comprehensive biophysical techniques such as UV–visible absorption spectroscopy, steady-state fluorescence spectroscopy, thermal fluorescence spectroscopy, viscosity (η) and dynamic light scattering (DLS) measurements. With the addition of 5 mg/mL of [Amim][Br] to the PNIPAM aqueous solution the LCST has been decreased towards lower temperatures. Further with the addition of higher concentration (10 and 15 mg/mL) of [Amim][Br] the decrease in the LCST of PNIPAM has been more pronounced towards lower temperatures. Our experimental results explicitly elucidated that the decrease in the LCST of the PNIPAM with increase in the concentration of [Amim][Br] is due to the substantial variations in the interactions among amide group of polymer, ions of ionic liquid and water molecules. The experimental results of the current investigation can be used for the design of smart polymer-based devices, as its LCST is close to body temperature. The results provide an alternative way to tune the phase transition temperature of the broadly accepted model PNIPAM polymer.

A new environmental-friendly imine compound viz. 4-(2-amino-3-methylphenyl)imino)methyl)benzaldehyde (AMIB) was sustainably synthesized at room temperature utilizing green solvents, reagents and assessed as an anti-corrosion catalyst for the commercially important mild steel (MS) alloy subjected to highly aggressive 0.5 M sulphuric acid (H2SO4) solution by several electrochemical methods (polarization techniques and Electrochemical impedance spectroscopy) allied with various surface characterization techniques such as attenuated total reflectance (ATR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and atomic force microscopy (AFM). Furthermore, the experimental results were theoretically supplemented by density functional theory (DFT) treatment. AMIB delivered significant corrosion protection even at very low concentrations and at various temperatures. The findings from electrochemical and surface characterization techniques were also supplemented by temperature kinetics study. The adsorption mechanism of AMIB molecules on metal substrate follow Langmuir's adsorption isotherm. The overall corrosion mitigation mechanism assessed from various techniques and methods was found to be comprehensive in nature. The present study may pave the way for combating corrosion with this cost effective and eco-friendly strategy.

The beguiling world of functional polymers is dominated by thermoresponsive polymers with unique structural and molecular attributes. Limited work has been reported on the protein-induced conformational transition of block copolymers; furthermore, the literature lacks a clear understanding of the influence of proteins on the phase behavior of thermoresponsive copolymers. Herein, we have synthesized poly(

The development of highly porous and thin separator is a great challenge for lithium-ion batteries (LIBs). However, the inevitable safety issues always caused by poor mechanical integrity and internal short circuits of the thin separator must be addressed before this type of separator can be applied to lithium-ion batteries. Here, we developed a novel multilayer poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) membrane with a highly porous and lamellar structure, through a combination of evaporation-induced phase separation and selective solvent etching methods. The developed membrane is capable of a greater amount of electrolyte uptake and excellent electrolyte retention resulting from its superior electrolyte wettability and highly porous structure, thereby offering better electrochemical performance compared to that of a commercial polyolefin separator (Celgard). Moreover, benefiting from the layered configuration, the tensile strength of the membrane can reach 13.5 MPa, which is close to the mechanical strength of the Celgard type along the transversal direction. The elaborate design of the multilayered structure allows the fabrication of a new class of thin separators with significant improvements in the mechanical and electrochemical performance. Given safer operation, the developed multilayer membrane may become a preferable separator required for high-power and high-energy storage devices.

Pesticide residues are posing an increasing threat to ecosystems and human health due to the over-application of synthetic pesticides in pest control to meet the global demand for agricultural food products. In this regard, electrochemical sensor and biosensor platforms have emerged as powerful analytical methods to detect pesticides due to several advantages, including synergistic aspects, systematic fabrication procedure, ease of detection, appreciable sensitivity, and selectivity. Furthermore, portable electrochemical devices have been fabricated recently for point-of-care and on-site detection of pesticides residues. This comprehensive review focuses on recent advances in portable electrochemical (bio)sensing methods for the on-site detection of pesticide residues in fruits and vegetables. Moreover, detailed information has been provided on the principal mechanism and electrochemical (bio)sensing behavior of the specified strategies. Discussed the significant developments in electrochemical strategies and the integration of smartphone technology with electrochemical sensing platforms for real-time monitoring. It is anticipated that the current review will be an added advantage and valuable tool for scientific and technological readers to understand the fabrication of portable electrochemical devices, the role of electrochemical (bio)sensing strategies for rapid on-site detection of pesticides, and to promote further developments in agricultural science, electrochemical science, and food science and technology.

1D, 2D and 3D- materials glazed biosensing has evolved and emerged as a new archetype for real-time health monitoring as well as a flawless human–machine interaction to perform point-of-care diagnostics. Smart nano bioengineering has emerged as a flawless system to fulfill the key requirements. Graphene glazed nanosystems have emerged as the foremost State-of-the-art materials due to their electrochemical activity, hydrophilicity, and functional group activity, which makes it advantageous for nano-devices based wearable assembly. Thin film fabrication, functionalization and controlled bio-active loads could be highly sensitive and selective nano-devices for early diagnosis of disease biomarkers at femtomolar level. In this letter, an overview has been provided on the potential applications of 2D-graphene for nano-bio-sensing system.

The improper disposal in agricultural and industrial wastewater leads to high NO

Consumption of sunset yellow (SY) above a certain concentration through food products may leads to adverse health issues. Therefore, it is imperative to develop technologies for rapid and selective detection of SY. Herein, a flower-like reduced graphene oxide (rGO)-graphitic carbon nitride (g-CN)/ZnO-Au nanoparticle (NPs) has been prepared and utilized for the specific detection of SY. The fabricated rGO-g-CN/ZnO-AuNPs composite was characterized and investigated by XRD, FTIR, SEM, TEM, XPS, EIS, and voltammetry techniques. Characterization techniques elucidated the deposition of ZnO-AuNPs on to the rGO-g-CN and successful fabrication of rGO-g-CN/ZnO-AuNPs composite. rGO-g-CN/ZnO-AuNPs composite possesses excellent catalytic activity for the oxidation of SY. Developed rGO-g-CN/ZnO-AuNPs sensor exhibits LOD of 1.34 nM for SY concentrations ranging from 5 to 85 nM. Noteworthily, the sensor has been successfully employed for the detection and recovery of SY in real-time samples. Fabricated composite opens up new avenues to develop electrochemical sensor for food safety.

Environmental hazards caused by chloramphenicol has attained special attention. Fast, accurate and reliable detection of chloramphenicol in foodstuffs and water samples is of utmost importance. Herein, we developed a g-C

Thermoresponsive polymers (TRPs) in different solvent media have been studied over a long period and are important from both scientific and technical points of view. Despite numerous studies on the behavior of TRPs with various additives, the interactions of additives with TRPs are still poorly understood. Moreover, despite the vast available literature regarding the biomolecular interactions between various TRPs and naturally occurring additives, it is not possible to provide a unifying declaration about the behavior of different additives, in particular at the phase transition temperature of the polymer. However, potential reviews that describe the behavior of additives as stimuli upon the phase transition of TRPs are also absent. A lack of sufficient knowledge regarding the responses of TRPs to additives as stimuli has hindered the expansion of the wide spectrum of applications of these polymers. Therefore, it was proposed to review the responses of TRPs in the presence of various additives in aqueous media. In-depth knowledge acquired via a literature survey has drawn our attention towards filling this gap by analyzing the interactions of TRPs with different additives. In this perspective, we have systematically examined the stability, aggregation, and phase transition behaviours of various polymers in the presence of different additives. The perspective on the influence of additives as stimuli on the behavior of TRPs in an aqueous medium will provide new reliable information about intramolecular interactions between interior polymer segments as well as intermolecular interactions between TRPs and additive molecules, which will be helpful for industrialists in the preparation of new polymeric materials for drug-delivery systems.

Agricultural food crop yields have increased enormously due to the implementation of chemical pesticides; however, their excessive and uncontrolled use has led to food contamination, as well as environmental, aquatic, and agricultural pollution. Therefore, on-site monitoring of pesticide residues in agricultural food products is crucial to ensure global food and environmental safety. Conventional pesticide detection strategies are time-consuming and unsuitable for on-site or on-field detection of pesticides. Among the current approaches for field detection of pesticides, including colorimetric, non-colorimetric, electrochemical, and optical sensing strategies, colorimetric sensing strategies exhibit the most promising potential for the on-site detection of pesticide residues due to their quick detection, easy fabrication, and high selectivity and sensitivity, in addition to being readable by the naked eye. Nonetheless, although pesticide quantification methods have been extensively described in the literature, only a few studies have conducted on-site pesticide residue analyses. Therefore, this study provides a comprehensive overview of the major advances in colorimetric sensing approaches based on nanoparticle aggregation, label-free hydrogel particles, lateral flow immunoassays (LFAs), integrated digital readers, portable field detection, and paper-based sensors for the on-site detection of pesticide residues in food crops. Moreover, this review also compares the analytical performances of the aforementioned strategies and discusses the new horizons, perspectives, and challenges associated with the development of portable devices. Therefore, we believe that this review provides important insights that might serve as the basis for the fabrication of novel colorimetric sensors with applicability in materials science, environmental science, food science, nanoscience, and biotechnology.

Coaxial fibers with ultra-thin two-dimensional (2D) structures (MXenes) provide promising advantages in biomedical applications. Here, a ternary structure of the MXene-FeWO4 heterostructure was synthesized by electrospinning FeWO4 bimetallic nanofibers followed by surface tagging on delaminated single-layered Ti3C2Tx MXenes. An electroactive interconnecting network of single-layered MXene with mixed metal-oxide fibers with high defective edge/plane sites exhibited significant electrocatalytic properties for rutin (RT) oxidation. Our findings highlighted the superior performance of the proposed material compared to bare glassy carbon electrodes (GCE), as well as WO3-GCE, FeWO4-GCE, MXene-GCE, and MXene-WO3-GCE electrodes in terms of overpotential and anodic peak intensity. Volumetric studies of the fabricated MXene-FeWO4 nanocomposite indicated an ultralow detection limit of 0.42 nM, an ultrawide linear determination range of 4–147 nM, and a high sensitivity of 0.3799 μA nM−1 cm−2. The MXene-FeWO4 nanocomposite also exhibited satisfactory stability and persistent anti-interference ability, as demonstrated by electrochemical characterization. Additionally, the MXene-FeWO4-GCE nanocomposite exhibited satisfactory recoveries when applied to detect RT in human serum, orange juice, and black tea samples. The developed sensor exhibited excellent RT selectivity and anti-interference ability compared to other interfering bioanalytes encountered in the present study. Therefore, our study provides the basis for the design of a hybrid composite network, thus opening exciting avenues for the development of high-performance electrochemical sensors in the biomedical and clinical fields.

In this research article, we have explored the changes in the lower critical solution temperature (LCST) of the poly(N-vinylcaprolactam) (PVCL) in the presence of imidazolium-based ionic liquids (ILs) with fixed cation 1-butyl-3-methylimidazolium cation [Bmim+], and commonly used anions such as SCN–, I–, Br–, Cl–, CH3COO–, and HSO4–. The series of anions also reflect the Hofmeister series of ILs. The results reveal that the LCST of the PVCL increases with increasing IL concentration. Interestingly, the results are the reverse of the PNIPAM with the same ILs where the LCST of PNIPAM decreases linearly with increase in the IL concentration following the Hofmeister series. Herein, we observed that the increase in the LCST of PVCL follows the order of ILs as, HSO4– < CH3COO– < Cl– < Br– < I– < SCN–. This is the reverse order for Hofmeister series anions effect on the polymer. Furthermore, the different kind of interactions occur between ILs and PVCL observed using UV-absorbance, fluorescence, and FTIR spectro...

The excessive use of food additives in manufactured food products negatively affects their quality and potentially impacts human health. In the present study, a composite consisting of gold nanoparticles decorated on tungsten carbide (AuNP-WC) was successfully fabricated using a facile and cost-effective ultrasonication technique. Compared to a bare glassy carbon electrode (GCE), AuNP-GCE, and WC-GCE, the AuNP-WC-GCE demonstrated excellent sensing performance for tert-butylhydroquinone (TBHQ) when used as an electrocatalyst in 0.05 M phosphate buffer solution (PBS), with a low working potential and a high peak current. In particular, the composite was able to detect the oxidation of TBHQ within a linear concentration range of 5 to 75 nM, with an extremely low detection limit of 0.20 nM. The practicability of the sensor was also assessed in the analysis of TBHQ in real samples of soybean oil, blended oil, and red wine, with satisfactory recovery rates obtained.

The improper disposal in agricultural and industrial wastewater leads to high NO2– concentrations in the aquatic environment, which can cause cancer in humans and animals; thus, their quick and accurate detection is urgently needed to ensure public health and environmental safety. In this study, a reliable and selective electrochemical sensor consisting of Pd–Cu nanospheres (NSs) supported on molybdenum carbide was prepared via simple ultrasonication. Then, a glassy carbon electrode was realized using this composite (Pd-Cu-Mo2C-modified GCE) to test its electrocatalytic sensing for NO2– in a 0.1 M phosphate-buffered solution (PBS) solution via cyclic voltammetry and amperometry; at a low oxidation potential, the anodic peak current of NO2– detected by this electrode was significantly higher than that of its unmodified and other modified electrodes. The sensor showed a broad linear response in the 5–165-nM NO2– concentration range, with a low detection limit (0.35 nM in 0.1 M PBS) and high sensitivity (3.308 μAnM–1 cm–2). Moreover, the fabricated electrode was successfully applied for detecting nitrites in sausages, river water, and milk, showing also good recovery.

In this work, densities (ρ), ultrasonic sound velocities (u) and viscosities (η) for binary mixture of tri(butyl)methylphosphonium methyl sulfate ([P4441][CH3SO4]) with N-methyl-2-pyrrolidone (NMP) were measured over the entire composition range at temperatures ranging from 293.15 to 323.15 K in steps of 5 K under atmospheric pressure. The derived properties such as excess molar volumes (VE), deviation in isentropic compressibilities (Δκs) and deviation in viscosities (Δη) are obtained from ρ, u and η data, respectively. The derived properties were correlated accurately with the Redlich-Kister type equation. The VE, Δκs and Δη values for the aforesaid systems are negative over the entire composition range under the present experimental conditions. The molecular interactions and structural effects were examined on the basis of measured and derived properties. The obtained results are useful for describing the intermolecular interactions, developing structure-property correlation and molecular modeling that exist between [P4441][CH3SO4] with NMP mixture.

To provide insights into the aggregation behavior, hydration tendency and variation in phase transition temperature produced by the addition of ionic liquids (ILs) to poly(N-isopropylacrylamide) (PNIPAM) aqueous solution, systematic physicochemical studies, and molecular dynamic simulations were carried out. The influence of ILs possessing the same [Cl]− anion and a set of cations [Cnmim]+ with increasing alkyl chain length such as 1-ethyl-3-methylimidazolium ([Emim]+), 1-allyl-3-methylimidazolium ([Amim]+), 1-butyl-3-methylimidazolium ([Bmim]+), 1-hexyl-3-methylimidazolium ([Hmim]+), 1-benzyl-3-methylimidazolium ([Bzmim]+), and 1-decyl-3-methylimidazolium ([Dmim]+) on the phase transition of PNIPAM was monitored by the aid of UV–visible absorption spectra, fluorescence intensity spectra, viscosity (η), dynamic light scattering (DLS), and Fourier transform infrared (FTIR) spectroscopy. Furthermore, to interpret the direct images and surface morphologies of the PNIPAM–IL aggregates, we performed field emis...

Different biophysical techniques such as fluorescence spectroscopy, dynamic light scattering (DLS), viscosity (η) and Fourier transform infrared (FTIR) spectroscopy have been carried out to characterize the effect of imidazolium-based ionic liquids (ILs) on the thermo-responsive triblock copolymer, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly-(ethylene glycol) (PEG-PPG-PEG). In addition, to demonstrate the distinct morphological changes of various self-assembled morphologies, we further employed field emission scanning electron microscope (FESEM). To investigate the effect of alkyl chain length of the cation, concentration of the ILs and the related Hofmeister series on the phase behaviour of PEG-PPG-PEG, we used a series of ILs possessing same Cl- anion and a set of cation [Cnmim]+ with increasing alkyl chain length of cation such as 1-ethyl-3-methylimidazolium chloride ([Emim][Cl]), 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]), 1-hexyl-3-methylimidazolium chloride ([Hmim][Cl]) and 1-decyl-3-methylimidazolium chloride ([Dmim][Cl]). The critical micellization temperature (CMT) of the copolymer in the presence of well hydrated cations is directly correlated to their hydration. The overall specific ranking of ILs in decreasing the CMT of PEG-PPG-PEG in aqueous solution was [Emim][Cl]>[Bmim][Cl]>[Hmim][Cl]>[Dmim][Cl]. The trend of these ILs followed the well-known Hofmeister series of cations of ILs. The present study provides important information about the solution properties that can be helpful to tune the IL or temperature-sensitive copolymer CMT and micelle shapes which are crucial for understanding the drug delivery mechanisms.

The influence of different alkylammonium-based ionic liquids (ILs) on the temperature-dependent aqueous poly( N -isopropylacrylamide) (PNIPAM) solution is explored by the comprehensive experimental analysis. The co-solvents investigated in the present study included a series of ILs with a fixed (trifluromethylsulfonyl)imide [NTf 2 ] − anion and variable ammonium cations such as butyltrimethylammonium (IL-1), methyl-trioctylammonium (IL-2), diethylmethyl(2-methoxyethyl)ammonium (IL-3) and ethyldimethylpropylammonium (IL-4). The thermal phase transitions of aqueous solution of thermo-responsive polymer (TRP) in ammonium-based ILs were studied by various experimental techniques such as fluorescence spectroscopy, dynamic light scattering (DLS) and viscosity ( η ). We further employed field emission scanning electron microscope (FESEM) to reveal the distinct morphological changes of various self-assembled morphologies. Our results reveal that the lower critical solution temperature (LCST) of the TRP can be significantly altered by the ILs. The phase transition state of aqueous TRP decreases as the concentration of IL increased. We find that IL-4 lowers the LCST of TRP significantly more as compared to the other ILs. Our experimental results reveal that the hydrophobic interactions are predominant between the monomers of PNIPAM and ions of the ILs. This research work highlights new opportunities for the wide applications in engineering of the bio-responsive smart PNIPAM-based devices and appropriate selection of ILs, which should allow for increasing the usage of thermo-responsive phase behaviour of polymers.