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Frontiers in Veterinary Science 2022Clay minerals are naturally occurring rock and soil materials primarily composed of fine-grained aluminosilicate minerals, characterized by high hygroscopicity. In... (Review)
Review
Clay minerals are naturally occurring rock and soil materials primarily composed of fine-grained aluminosilicate minerals, characterized by high hygroscopicity. In animal production, clays are often mixed with feed and, due to their high binding capacity towards organic molecules, used to limit animal absorption of feed contaminants, such as mycotoxins and other toxicants. Binding capacity of clays is not specific and these minerals can form complexes with different compounds, such as nutrients and pharmaceuticals, thus possibly affecting the intestinal absorption of important substances. Indeed, clays cannot be considered a completely inert feed additive, as they can interfere with gastro-intestinal (GI) metabolism, with possible consequences on animal physiology. Moreover, clays may contain impurities, constituted of inorganic micronutrients and/or toxic trace elements, and their ingestion can affect animal health. Furthermore, clays may also have effects on the GI mucosa, possibly modifying nutrient digestibility and animal microbiome. Finally, clays may directly interact with GI cells and, depending on their mineral grain size, shape, superficial charge and hydrophilicity, can elicit an inflammatory response. As in the near future due to climate change the presence of mycotoxins in feedstuffs will probably become a major problem, the use of clays in feedstuff, given their physico-chemical properties, low cost, apparent low toxicity and eco-compatibility, is expected to increase. The present review focuses on the characteristics and properties of clays as feed additives, evidencing pros and cons. Aims of future studies are suggested, evidencing that, in particular, possible interferences of these minerals with animal microbiome, nutrient absorption and drug delivery should be assessed. Finally, the fate of clay particles during their transit within the GI system and their long-term administration/accumulation should be clarified.
PubMed: 35619608
DOI: 10.3389/fvets.2022.889612 -
Scientific Reports Nov 2023A robust, stability-indicating, and eco-friendly proton nuclear magnetic resonance (H-qNMR) method was developed for the concurrent determination of three...
Utility and greenness appraisal of nuclear magnetic resonance for sustainable simultaneous determination of three 1,4-benzodiazepines and their main impurity 2-amino-5-chlorobenzophenone.
A robust, stability-indicating, and eco-friendly proton nuclear magnetic resonance (H-qNMR) method was developed for the concurrent determination of three 1,4-benzodiazepines (BDZs), namely diazepam (DZP), alprazolam (ALP), and chlordiazepoxide (CDP) and their common impurity, synthesis precursor, and degradation product; 2-amino-5-chlorobenzophenone (ACB). In the present method, a novel approach was developed for composing a green and cost-efficient solvent system as an alternative to the common NMR organic solvents utilizing 0.3 M sodium dodecyl sulfate prepared in deuterated water. The conducted method is characterized by simplicity with no need for sample pretreatment or labeling. Phloroglucinol was used as an internal standard. The chosen signals for the determinations of ALP, CDP, DZP and ACB were at 2.35 ppm (singlet), 2.84 ppm (singlet), 3.11 ppm (singlet), and 6.90 ppm (doublet of doublet), respectively. The proposed method possessed linearity over the concentration range of 0.25-15.0 mg ml for DZP, ALP, CDP and of 0.5-25.0 mg ml for ACB with LOD values of 0.06, 0.03, 0.07 and 0.16 mg ml respectively, and LOQ values of 0.18, 0.09, 0.21 and 0.49 mg ml, respectively. Accuracy of the method was evidenced by excellent recovery% (99.57-99.90%) and small standard deviation (≥ 1.10) for the three analyzed drugs. Intra- and inter-day precision were determined with coefficient of variation ranging from 0.12 to 1.14 and from 0.72 to 1.67, respectively. For the studied compounds, appraisal of the method greenness was achieved via four approaches: Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), Analytical greenness metric (AGREE), and RGB Additive Color Model. The results proved that the proposed method has the privilege of being a green analytical method.
Topics: Benzodiazepines; Benzophenones; Diazepam; Magnetic Resonance Spectroscopy; Solvents
PubMed: 38036558
DOI: 10.1038/s41598-023-48416-7 -
Scientific Reports Nov 2022Agriculture plays a crucial role in safeguarding food security, more so as the world population increases gradually. A productive agricultural system is supported by...
Agriculture plays a crucial role in safeguarding food security, more so as the world population increases gradually. A productive agricultural system is supported by seed, soil, fertiliser and good management practices. Food productivity directly correlates to the generation of solid wastes and utilization of agrochemicals, both of which negatively impact the environment. The rice and paddy industry significantly adds to the growing menace of waste management. In low and middle-income countries, rice husk (RH) is an underutilized agro-waste discarded in landfills or burned in-situ. RH holds enormous potential in the development of value-added nanomaterials for agricultural applications. In this study, a simple and inexpensive sol-gel method is described to extract mesoporous silica nanoparticles (MSNs) from UKMRC8 RH using the bottom-up approach. RHs treated with hydrochloric acid were calcinated to obtain rice husk ash (RHA) with high silica purity (> 98% wt), as determined by the X-ray fluorescence analysis (XRF). Calcination at 650 °C for four hours in a box furnace yielded RHA that was devoid of metal impurities and organic matter. The X-ray diffraction pattern showed a broad peak at 2θ≈20-22 °C and was free from any other sharp peaks, indicating the amorphous property of the RHA. Scanning electron micrographs (SEM) showed clusters of spherically shaped uniform aggregates of silica nanoparticles (NPs) while transmission electron microscopy analysis indicated an average particle size of < 20 nm. Besides Energy Dispersive X-Ray which validated the chemical constituent of the silica NPs, the Fourier transform infrared (FT-IR) spectra showed peaks at 796.4 cm and 1052 cm corresponding to O-Si-O symmetric stretching vibration and O-Si-O asymmetric stretching, respectively. The Brunauer-Emmet-Teller (BET) analysis indicated an average pore size = 8.5 nm while the specific surface area and the pore volume were 300.2015 m/g and 0.659078 cm/g, respectively. In conclusion, agrowaste-derived MSN was synthesized using a simple and economical sol-gel method without the addition of surfactant reagents for controlled formation at the structural level. Owing to the MSNs' excellent physical properties, the method established herein, could be used singly (without any modifications) for the functionalization of a myriad of agrochemicals.
Topics: Silicon Dioxide; Oryza; Spectroscopy, Fourier Transform Infrared; Nanoparticles; Agriculture; Agrochemicals
PubMed: 36424408
DOI: 10.1038/s41598-022-24484-z -
Se Pu = Chinese Journal of... Apr 2021Istradefylline is a novel selective adenosine A receptor antagonist that is used to treat Parkinson's disease and improve motor dysfunction in the early stage of this...
Istradefylline is a novel selective adenosine A receptor antagonist that is used to treat Parkinson's disease and improve motor dysfunction in the early stage of this disease. During the synthesis of intermediate A1 (6-amino-1,3-diethyl-2,4-(1,3)-pyrimidinedione), at least two by-products were formed under alkaline or high-temperature conditions. In a previous study, one of the by-products in the synthesis of the intermediate was studied, and its structure was identified as ()-ethyl-2-cyano-3-ethylamino-2-butene amide. In this study, we used high performance liquid chromatography (HPLC) to analyze another impurity formed during the synthesis of A1, and the following steps were executed: 0.4 g of intermediate was weighed and added to a 50 mL beaker, followed by the sequential addition of 8 mL water and 8 mL acetonitrile, and then, ultrasonic dissolution was performed. Finally, the solution was filtered through a 0.45-μm organic membrane and the test sample solution was obtained. We used the Agilent zorbax C18 chromatography column, with acetonitrile (A)/water(B) as the mobile phase under gradient elution ((/A∶B)=/20∶80, /60∶40, -/90∶10). The detector wavelength is 268 nm. In order to separate the impurity from A1, we used a Ceres B preparative column, with acetonitrile-water (30/70, v/v) as the mobile phase. The flow rate was set at 30 mL/min, and the detection wavelength was 268 nm. The structure of the impurity was confirmed by high-resolution mass spectrometry (HRMS), one-dimensional nuclear magnetic resonance (NMR), and two-dimensional nuclear magnetic resonance (2D NMR), and characterized by single-crystal X-ray diffraction (XRD). In MS experiments, an electrospray ionization (ESI) source was used with positive ion scanning. In the NMR experiments, we used tetramethylsilane (TMS) as the internal standard and deuterated dimethyl sulfoxide (DMSO-d) as the solvent to obtain the spectra. The results of preparative high performance liquid chromatography (Prep-HPLC) showed that good separation effect could be achieved by isocratic elution, and the impurity was perfectly separated. TheH-NMR spectral data are as follows:H-NMR (600 MHz, DMSO): 1.01 (q, =6.9 Hz, 3H), 1.02 (q, =6.9 Hz, 3H), 1.07 (t, =6.9 Hz, 3H), 3.04 (p, =6.8 Hz, 2H), 3.74 (q, =7.0 Hz, 2H), 3.94 (q, =7.1 Hz, 2H), 5.85 (s, 1H). The C-NMR spectral data are summarized as follows: C-NMR (150 MHz, DMSO): 13.9, 14.1, 15.9, 34.6, 34.9, 36.9, 81.9, 152.2, 153.3, 159.3, 162.0. The impurity was characterized by single-crystal XRD, and its spatial structure was further verified and determined as 1-(1,3-diethyl-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-yl)-3-ethylurea. Based on the chemical structure of the impurity, we propose the following mechanism for the impurity: when A1 is synthesized under alkaline conditions or at high temperature, excessive diethylurea continues to undergo amidation with A1 to obtain this by-product. Although the formation mechanism of the impurity studied in this paper is different from that of the intermediate A1 impurity ()-ethyl-2-cyano-3-ethylamino-2-butene amide, both the impurities are formed at high temperatures. Both will be accompanied by A1 in the subsequent reaction of istradefylline synthesis. The relationship between drug impurities and drug safety is a complex relationship that is affected by many factors. Generally, most impurities in drugs have potential biological activities, and some even interact with the drugs, thus affecting their efficacy and safety and inducing toxic effects. Therefore, to ensure the quality of istradefylline, it is necessary to control the impurity content during the production. The findings of this paper may provide guidelines for controlling the impurity content in istradefylline.
Topics: Chromatography, High Pressure Liquid; Drug Contamination; Mass Spectrometry; Purines
PubMed: 34227764
DOI: 10.3724/SP.J.1123.2020.10013 -
Nanomaterials (Basel, Switzerland) May 2023Photovoltaics are being transformed by perovskite solar cells. The power conversion efficiency of these solar cells has increased significantly, and even higher...
Photovoltaics are being transformed by perovskite solar cells. The power conversion efficiency of these solar cells has increased significantly, and even higher efficiencies are possible. The scientific community has gained much attention due to perovskites' potential. Herein, the electron-only devices were prepared by spin-coating and introducing the organic molecule dibenzo-18-crown-6 (DC) to CsPbIBr perovskite precursor solution. The current-voltage (I-V) and J-V curves were measured. The morphologies and elemental composition information of the samples were obtained by SEM, XRD, XPS, Raman, and photoluminescence (PL) spectroscopies. The distinct impact of organic DC molecules on the phase, morphology, and optical properties of perovskite films are examined and interpreted with experimental results. The efficiency of the photovoltaic device in the control group is 9.76%, and the device efficiency gradually increases with the increase of DC concentration. When the concentration is 0.3%, the device efficiency is the best, reaching 11.57%, short-circuit current is 14.01 mA/cm, the open circuit voltage is 1.19 V, and the fill factor is 0.7. The presence of DC molecules effectively controlled the perovskite crystallization process by inhibiting the in-situ generations of impurity phases and minimizing the defect density of the film.
PubMed: 37299654
DOI: 10.3390/nano13111751 -
ACS Omega Mar 2022Surface contamination experienced during polymer-assisted transfer is detrimental for optical and electrical properties of 2D materials. This contamination is usually...
Surface contamination experienced during polymer-assisted transfer is detrimental for optical and electrical properties of 2D materials. This contamination is usually due to incomplete polymer removal and also due to impurities present in organic solvents. Here, we report a simple, economical, and highly efficient approach for obtaining pristine graphene on a suitable substrate (e.g., SiO/Si) by utilizing Soxhlet extraction apparatus for delicate removal of the polymer with a freshly distilled ultrapure solvent (acetone) in a continuous fashion. Excellent structural and morphological qualities of the material thus produced were confirmed using optical microscopy, atomic force microscopy, scanning electron microscopy, and Raman spectroscopy. Compared to the conventional protocol, graphene produced by the current approach has a lower residual polymer content, leading to a root mean square roughness of only 1.26 nm. The amount of strain and doping was found to be similar, but the D-band, which is indicative of the defects, was less pronounced in the samples prepared by Soxhlet-assisted transfer. The new procedure is virtually effortless from the experimental point of view, utilizes much less solvent compared to the conventional washing procedure, and allows for easy scale-up. Extension of this process to other 2D materials would not only provide samples with superior intrinsic properties but also enhance their suitability for advanced technological applications.
PubMed: 35252719
DOI: 10.1021/acsomega.1c07113 -
Ayu 2022Water is vital for life as the body uses water in all its cells and tissues to maintain vital functions. Hence, water used for drinking should be free from all types of...
BACKGROUND
Water is vital for life as the body uses water in all its cells and tissues to maintain vital functions. Hence, water used for drinking should be free from all types of impurities. Acharya Sushruta has mentioned various water purification methods by keeping it in different types of vessels (silver, copper, and clay) and by adding herbs such as (seeds Linn.). With urbanization, there are changes in the lifestyle of individuals and their food habits. Therefore, based on the ease of availability of materials, storage of water needs to be analyzed by simple parameters such as total dissolved solutes (TDS) that comprises inorganic salts such as bicarbonates, sulfates, and chlorides and a small amount of organic matter that is dissolved in water. A high level of TDS indicates water is unfit for consumption and may lead to nausea, vomiting, dizziness, etc., TDS level indicates whether water is suitable for consumption or it requires filtration.
AIM
To evaluate and compare the TDS of water kept for 24 h in different vessels made up of silver, copper, clay, plastic, and steel and further with the addition of different herbs like seeds, leaves ( Linn.), leaves ( A. Juss) separately in different vessels.
MATERIALS AND METHODS
The effect of different materials used for storage of water was assessed by evaluating TDS in water samples with the help of a well-calibrated TDS meter, on stored water (100 ml) in different types of vessels (silver, copper, clay, plastic, and steel) and further with the addition of different herbs (10 g) seeds, leaves and leaves individually and separately, by keeping undisturbed for 24 h.
RESULTS
TDS values of the water samples kept for 24 h in different vessels, i.e., silver, copper, plastic, steel, and clay are 372, 429, 436, 445, 628 ppm, respectively, were found.
CONCLUSION
The silver vessel was found to be best in decreasing the TDS value of water among vessels. On evaluating additional effects by adding different herbs, showed its action best among the storage vessels.
PubMed: 37554414
DOI: 10.4103/ayu.ayu_366_20 -
Nanomaterials (Basel, Switzerland) Aug 2021Doping and its consequences on the electronic features, optoelectronic features, and magnetism of graphynes (GYs) are reviewed in this work. First, synthetic strategies... (Review)
Review
Doping and its consequences on the electronic features, optoelectronic features, and magnetism of graphynes (GYs) are reviewed in this work. First, synthetic strategies that consider numerous chemically and dimensionally different structures are discussed. Simultaneous or subsequent doping with heteroatoms, controlling dimensions, applying strain, and applying external electric fields can serve as effective ways to modulate the band structure of these new sp/sp allotropes of carbon. The fundamental band gap is crucially dependent on morphology, with low dimensional GYs displaying a broader band gap than their bulk counterparts. Accurately chosen precursors and synthesis conditions ensure complete control of the morphological, electronic, and physicochemical properties of resulting GY sheets as well as the distribution of dopants deposited on GY surfaces. The uniform and quantitative inclusion of non-metallic (B, Cl, N, O, or P) and metallic (Fe, Co, or Ni) elements into graphyne derivatives were theoretically and experimentally studied, which improved their electronic and magnetic properties as row systems or in heterojunction. The effect of heteroatoms associated with metallic impurities on the magnetic properties of GYs was investigated. Finally, the flexibility of doped GYs' electronic and magnetic features recommends them for new electronic and optoelectronic applications.
PubMed: 34578583
DOI: 10.3390/nano11092268 -
Environmental Chemistry Letters 2021Silica nanoparticles have rapidly found applications in medicine, supercapacitors, batteries, optical fibers and concrete materials, because silica nanoparticles have... (Review)
Review
Silica nanoparticles have rapidly found applications in medicine, supercapacitors, batteries, optical fibers and concrete materials, because silica nanoparticles have tunable physical, chemical, optical and mechanical properties. In most applications, high-purity silica comes from synthetic organic precursors, yet this approach could be costly, polluting and non-biocompatible. Alternatively, natural silica sources from biomass are often cheap and abundant, yet they contain impurities. Silica can be extracted from corn cob, coffee husk, rice husk, sugarcane bagasse and wheat husk wastes, which are often disposed of in rivers, lands and ponds. These wastes can be used to prepare homogenous silica nanoparticles. Here we review properties, preparation and applications of silica nanoparticles. Preparation includes chemical and biomass methods. Applications include biosensors, bioimaging, drug delivery and supercapacitors. In particular, to fight the COVID-19 pandemic, recent research has shown that silver nanocluster/silica deposited on a mask reduces SARS-Cov-2 infectivity to zero.
PubMed: 33199978
DOI: 10.1007/s10311-020-01123-5 -
Se Pu = Chinese Journal of... Oct 2022Hexabromocyclododecanes (HBCDs) are a group of brominated flame retardants that are extensively employed in the industrial production of plastics, furniture, and...
Hexabromocyclododecanes (HBCDs) are a group of brominated flame retardants that are extensively employed in the industrial production of plastics, furniture, and construction materials. Due to their regular use and massive emissions, HBCDs have been distributed in the environment (air, water, soil, and sediments). Due to their high toxicity, persistent and long-distance transport, and bioaccumulation, HBCDs were listed in the Stockholm Convention in 2013. Thus, the accurate analysis and strict control of the pollution levels of HBCDs in environmental samples are critical to the government's long-term environmental supervision mechanism. However, the concentration levels of HBCDs in real samples are low, combined with complex matrices, which seriously limits the determination of HBCDs. The target isomers are particularly transformed or degraded, which makes analysis challenging due to the high temperatures and specific organic solvents. The physicochemical features, toxic and environmental dangers, usage, and standard limitations of HBCDs are briefly discussed herein. Sample pretreatment and instrument detection of HBCDs in various matrices are summarized (i. e., soil, sediment, food, electronics, atmosphere, animals, and water). More than 70 research papers (2000-2022) from the Science Citation Index (SCI) and Chinese core publications are cited herein. First, the entire process of extraction, purification, separation, and enrichment of HBCDs is compared, including soxhlet extraction (SE), ultrasonic-assisted extraction (UAE), accelerated solvent extraction(ASE), supercritical fluid extraction (SFE), solid phase extraction (SPE), dispersed solid phase extraction (DSPE), liquid-liquid extraction (LLE), dispersive liquid-liquid microextraction (DLLME), and solid phase microextraction (SPME). In the literature, UAE is the most commonly employed process, accounting for a quarter of all HBCDs sample pretreatments. Additionally, SPE sample pretreatment technology can completely separate the targets and impurities to reduce the effect of matrix; and enrich the targets to improve sensitivity of method. By using SPE technology, the enrichment factor can be increased due to the massive sample volume, thus enabling detect HBCDs concentrations (nanogram per liter level) in water. Second, the advantages and disadvantages of instrument approaches are examined and discussed, including gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS), liquid chromatography (LC), and liquid chromatography-tandem mass spectrometry (LC-MS/MS), which offer a reference for meeting the requirements in the determination of HBCDs in real samples, i. e., the total HBCDs can be detected by GC or GC-MS and three HBCD isomers (α-HBCD, β-HBCD, γ-HBCD) can be determined by LC or LC-MS. By using the triple quadrupole mass spectrometer, the sensitivity of the method can be improved. Till date, LC-MS/MS has been chosen as an instrument for the determination of HBCDs in various matrices (i. e., seawater, marine sediment, marine organisms, toys, and electronic products) in China. However, there are several challenges. The sample pretreatment is tedious; large sample volumes and organic solvent utilization. These challenges point to the development trends of analytical approaches for HBCDs. The development of green, automated, low-cost, fast, and efficient sample pretreatment approaches for new adsorption materials is the main development direction in the analysis of HBCDs in the future.
Topics: Animals; Chromatography, Liquid; Flame Retardants; Gas Chromatography-Mass Spectrometry; Hydrocarbons, Brominated; Plastics; Soil; Solvents; Tandem Mass Spectrometry; Water
PubMed: 36222250
DOI: 10.3724/SP.J.1123.2022.03030