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We describe the creation of a solid-state optical sensor that is quick to respond, sensitive, and reliable for detecting and determining Cu(II) ions in both natural and wastewater sources. The solid-state template was prepared with mesoporous silica nanospheres of capacious porosity, high surface area, and uniform surface morphology. N,N'-bis(3-carboxysalcylidene)-4-chloro-1,2-phenylenediamine (CSCPD), a chromoionophoric probe with exclusive ion-selectivity and sensitivity for Cu(II), is created for use in naked-eye colorimetric detection. The mesoporous silica nanospheres (MSNs) template displayed several diffusible sites for the uniform anchoring of the CSCPD probe molecules, which serve as a colorimetric ion sensor for the naked eye. The surface profile and structure of the MSNs and the CSCPD sensor materials are studied using BET/BJH, XPS, FESEM, p-XRD, and HR-TEM analysis. With various concentrations of Cu(II), the CSCPD probe-anchored MSNs material reciprocates a vivid visual colour shift from an initial pale yellow colour to green with a reaction period of around one minute. In addition, the MSNs are simply covered with probe molecules as part of the sensor production process. The certified limits of detection for Cu(II) ions for the proposed CSCPD sensor is 1.57 ppb (2.48 × 10−8 M). The suggested CSCPD sensor is dual-functional in that it may be used as a concentrator to recover ultra-trace quantities of Cu(II) ions as well as an effective ion-sensing device. [ABSTRACT FROM AUTHOR]

Diuretics are drugs that promote the excretion of water and electrolytes in the body and produce diuretic effects. Clinically, they are often used in the treatment of edema caused by various reasons and hypertension. In sports, diuretics are banned by the World Anti-Doping Agency (WADA). Therefore, in order to monitor blood drug concentration, identify drug quality and maintain the fairness of sports competition, accurate, rapid, highly selective and sensitive detection methods are essential. This review provides a comprehensive summary of the pretreatment and detection of diuretics in various samples since 2015. Commonly used techniques to extract diuretics include liquid-liquid extraction, liquid-phase microextraction, solid-phase extraction, solid-phase microextraction, among others. Determination methods include methods based on liquid chromatography, fluorescent spectroscopy, electrochemical sensor method, capillary electrophoresis and so on. The advantages and disadvantages of various pretreatment and analytical techniques are elaborated. In addition, future development prospects of these techniques are discussed. HIGHLIGHTS: Pretreatment and determination methods of diuretics in diverse samples are reviewed. Applications of novel materials and technologies for SPE and sensors are highlighted. Pros and cons of recent pretreatment and analysis techniques used for diuretics are discussed. Applications of high-resolution mass spectrometry are described in detail. [ABSTRACT FROM AUTHOR]

During the COVID-19 process, determination-based analytical chemistry studies have had a major place at every stage. Many analytical techniques have been used in both diagnostic studies and drug analysis. Among these, electrochemical sensors are frequently preferred due to their high sensitivity, selectivity, short analysis time, reliability, ease of sample preparation, and low use of organic solvents. For the determination of drugs used in the SARS-CoV-2, such as favipiravir, molnupiravir, ribavirin, etc., electrochemical (nano)sensors are widely used in both pharmaceutical and biological samples. Diagnosis is the most critical step in the management of the disease, and electrochemical sensor tools are widely preferred for this purpose. Diagnostic electrochemical sensor tools can be biosensor-, nano biosensor-, or MIP-based sensors and utilize a wide variety of analytes such as viral proteins, viral RNA, antibodies, etc. This review overviews the sensor applications in SARS-CoV-2 in terms of diagnosis and determination of drugs by evaluating the most recent studies in the literature. In this way, it is aimed to compile the developments so far by shedding light on the most recent studies and giving ideas to researchers for future studies. [ABSTRACT FROM AUTHOR]

Fish are good sources of protein however when they contain toxic metals, they can pose health risk to human beings. Percentage moisture and ash contents were determined using oven dry weight and furnace methods respectively. Also, the concentrations (mg/Kg) of Cd, Cr and Cu in the tissue of catfish, tilapia and croaker fish were determined using an atomic absorption spectrophotometer (AAS). Estimated daily intake of Cd, Cr and Cu, hazard quotient, hazard index, and cancer risk were evaluated. The result showed 4.25±0.35 % (catfish), 5.25±0.45 % (tilapia fish) and 4.50±0.00 % (croaker fish) for moisture, 1.75±0.35 % (cat fish), 2.25±0.23 (tilapia fish) and 2.25±0.23 % (croaker fish) for ash content. The concentrations of Cd, Cr and Cu in the species of fish determined were above the threshold WHO/FAO (0.02 mg/kg) limit. The THQ for Cu was greater than 1 while Dc and Cr were less than 1. This indicates that the level of Cu in the species of fish determined will lead to a non-carcinogenic effect on consumers. [ABSTRACT FROM AUTHOR]

A unique and irregular form distorted Cu2(V2O7) sphere with crumbled sheets of rGO nanocomposite was developed as a sensor over a glassy carbon electrode (GCE). It showed a higher sensitivity for an antipsychotic drug, pimozide (PMZ). Voltammetric techniques were used to investigate the electrochemical behavior of PMZ. The formation of Cu2(V2O7)-rGO nanocomposite was confirmed by X-ray diffraction analysis. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to examine the surface morphology and its properties. Cyclic voltammetric studies revealed that PMZ displayed intense electrocatalytic activity and exhibited an electro-oxidation peak at the modified electrode. The modified electrode possessed unique qualities such as fast electron transfer ability, repeatability, and reproducibility. The proposed differential pulse voltammetric (DPV) and square wave voltammetric (SWV) methods showed linearity in the concentration range of 5.12 × 10−9 M to 3.06 × 10−4 M and 1.02 × 10−9 M to 5.30 × 10−4 M, respectively. The limit of detection (LOD) was calculated to be 1.70 × 10−10 M and 8.52 × 10−11 M, while the limit of quantification (LOQ) was found to be 5.66 × 10−10 M and 2.84 × 10−10 M, respectively, for DPV and SWV methods. The developed methods were successfully applied for the determination of PMZ in pharmaceutical formulations and human urine samples. [ABSTRACT FROM AUTHOR]

Phthalate esters are commonly included in the formulations of cosmetics and related products in order to retain fragrance, enhance flexibility (i.e., by acting as plasticizers), facilitate the dissolution and dispersion of other ingredients, and improve the overall texture and sensory experience of the products. This study aimed to assess the presence and concentrations of phthalates in cosmetics by analyzing a comprehensive set of samples collected over a period of five years (2016–2020). The concentrations of nine different phthalate esters (BBP, DEHP, DNOP, DPP, DBP, DIPP, DMEP, DMP and PIPP) in 1110 cosmetics samples from France and Spain were determined by gas chromatography–mass spectrometry. The samples were included in five categories: soaps and shampoos; hand and body creams; lip gloss and lipsticks; nail polish; and facial makeup and skincare products. Some of the samples (4.86%) contained at least one phthalate at concentrations above the threshold limit (1 µg mL−1). Variable concentrations of different phthalates were determined in the 54 positive samples identified. DEHP was the most frequently detected phthalate, followed by DBP. The findings revealed different profiles according to the different categories of cosmetics and the phthalates detected in each. The results were critically compared with those obtained in various previous studies. [ABSTRACT FROM AUTHOR]

A sorbent with magnetic properties, functionalized with humates, in combination with gas chromatography–mass spectrometry is proposed for the determination of phenolic xenoestrogens (ED) in bottom sediments. The octylphenol (OP), nonylphenol (NP), and bisphenol A (BPA) ED are chosen as test samples. Along with ED, the distribution of the naturally occurring estrogen, 17β-estradiol (ES), is studied. Sorption preconcentration is carried out under dynamic conditions: a sorbent weighing 0.5 g is placed in a borosilicate glass column, on both sides of which magnets are placed to immobilize the sorbent. The analytical characteristics of the determination method are established using model samples of bottom sediments selected in a background area with a minimal anthropogenic impact. The limit of quantification for ED is 30–60 ng/kg (dry weight). In analyzing real samples, the sensitivity of the method is reduced by 3–4 times due to matrix effects of the presence of petroleum products in waters. The ED content of bottom sediments at the site of wastewater discharge into the river Don near the city of Voronezh, as well as on the Black Sea coast of the Caucasus (area of the city of Tuapse and the village of Olginka) was monitored. The maximum concentrations of OP, NP, BPA, and ES in bottom sediments were found in the area of the port of Tuapse, where they were 5.7, 8.1, 6.2 and 0.9 µg/kg, respectively. [ABSTRACT FROM AUTHOR]

An original bench-scale installation based on the principles of online magnetic solid-phase extraction is developed. The setup includes a borosilicate glass column packed with Fe3O4@MIP-BPA, which is fixed with two neodymium magnets. Compared to using one magnet, a design with two magnets ensures the uniform distribution of the sorbent over the entire cross-section of the column. The highest concentration factors (EF = 3216) and the degree of desorption of bisphenol A (BPA) are achieved, respectively, at a volumetric solution flow rate (W) of 2.0 mL/min and with eluting BPA with methanol (W = 0.4 mL/min). The determination of BPA in concentrates from model media by GC−MS provides high sensitivity of the developed method for determining BPA. In analyzing model solutions prepared in distilled water, the limit of detection (LOD) is 0.3 ng/L. In analyzing river water, the LOD increases by approximately 2 times. In analyzing soils, LOD = 2.2 ng/kg dry weight. Soils, compared to water bodies, contain a larger number of interfering components; the sensitivity of the method is reduced by 7–8 times. Bottom sediments are even more contaminated; the LOD more than doubles compared to the determination of BPA in soils. [ABSTRACT FROM AUTHOR]

Crude palm oil (CPO) production continues to be accelerated every year to meet domestic needs and large export demands from China, India, Pakistan, Bangladesh, Japan, and countries in the Middle East region. Indonesia, as the largest CPO producer in the world, is taking on this role to increase the country's competitiveness by continuing to meet CPO demand and needs. However, the high level of CPO processing impacts increasing by-products from palm oil factories. Empty bunches fruit from Palm oil (EFB) are the most common by-product of CPO production. This is a big problem because accumulation will be the main source of environmental damage and pest explosions. Processing EFB into soil conditioners can be an initiative to reduce the accumulation of EFB in factories. However, its effect is not yet known with certainty on several plants cultivated on marginal dry land, such as Ultisol soil. Research aimed to analyze the relationship between the application of various EFB composts to bulk density, percentage of water content, degree of soil acidity, increase in number of leaves, number of eggplants, and weight of eggplant. The research results showed that EFB in the form of compost applied could influence the bulk density, percentage of water content, degree of soil acidity, increase in the number of leaves, and weight of eggplant, but did not affect the number of eggplant. Application EFB positively correlated with the percentage of water content, degree of soil acidity, increase in number of leaves, and weight of eggplant, with determination effects. At the same time, EFB compost had a negative correlation with bulk density. [ABSTRACT FROM AUTHOR]

The study of the reproduction characteristics of roses of the garden class Shrub, the definition of the dependence of the hormonal determination of explant rhizogenesis on the concentrations of phytohormones that are part of the nutrient medium, are relevant and has both scientific and practical interest. This study presents the results of studies of hormonal determination of rhizogenesis in explants of cultivars of roses of the garden class Shrub: Gärtnerfreude, Lavender Dream, Pomponella, Red Cascade, Sommerabend cultivated in vitro on nutrient medium containing growth regulators. It has been established that of the nutrient medium modified by the addition of 0.2-1.0 mg/l α-naphthylacetic acid (α-NAA), the most effective was the medium with the content of α-NAA 0.5 mg/l, the content of macro- and microelements half of the Murashige and Skoog prescriptions, and a decrease in the sucrose content to 2.0%. On this medium, the frequency of rhizogenesis averaged 61.2% for the studied cultivars. Hormonal determination of rhizogenesis and efficiency of root formation in vitro in the Shrub rose regenerants depended on the genotype of the plant: cv. Lavender Dream (66.0%) and cv. Sommerabend (67.0%) had the highest rhizogenesis ability. The use of the universal growth regulator Humifield in combination with 0.5 mg/l α-NAA contributed to an increase in the rooting rate of the studied rose cultivars up to 70.0-86.0%. [ABSTRACT FROM AUTHOR]

Cranial suture closure has long been understood as an indicator of human development and is closely associated with the aging process. Due to this correlation, it has been widely used in forensic and archaeological contexts to estimate the age of unidentified or skeletonized individuals. Several cadaverbased studies have demonstrated the usefulness of the lambdoid suture in age estimation; however, it is not a technique that is commonly applied in routine forensic practice. Age estimation plays a crucial role in developing the biological profile that forensic anthropologists use to help identify unknown deceased individuals. This study aims to examine the pattern of cranial vault suture closure and its relationship to age, thereby contributing to more accurate age determination in forensic investigations. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) and spherical barium molybdate (BaMoO4) crystal were prepared using hydrothermal method, respectively. The rGO-BaMoO4 composite was then formed by sonication mixing. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were applied to characterize the microstructure of rGO-BaMoO4 composite. Moreover, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) techniques were utilized to investigate its electrochemical performance. Due to the synergistic effect of the two materials, the rGO-BaMoO4 composite modified glassy carbon electrode (rGO-BaMoO4/GCE) exhibits superior electroanalytical performance toward sunset yellow (SY) and tartrazine (TZ) assay, including wide linear range from 0.1 to 1.0 µmol/L and 1.0 to 80 µmol/L, low detection limits of 0.070 (for SY) and 0.078 µmol/L (for TZ), excellent selectivity, good reproducibility, and high stability. What is more, the constructed rGO-BaMoO4/GCE was applied for the assay of SY and TZ in commercial beverage samples. The satisfactory recoveries of 97-108% obtained in real samples reveal the potential of rGO-BaMoO4/GCE in practical applications. [ABSTRACT FROM AUTHOR]

The growing prevalence of pharmaceutical compounds in the environment raises significant concerns due to their potential impacts on ecological and human health. This present manuscript focuses on the methods used to extract and determine these pharmaceuticals in water samples. It provides a comprehensive analysis of the extraction techniques and analytical approaches employed for the identification and quantification of pharmaceuticals in environmental water. Due to their chemical properties and widespread use, pharmaceuticals persist in the environment and contaminate water bodies, soil, and sediments. The presence of pharmaceuticals in the aquatic environment has been linked to several adverse effects on aquatic organisms, including the disruption of physiological processes and reproductive impairment. Furthermore, pharmaceuticals in the environment can affect human health through food and drinking water contamination and contribute to antibiotic resistance. The analysis of pharmaceutical contaminants in water samples presents several challenges due to the complex matrix and low concentrations of target substances. Various sample preparation techniques and protocols, including solid-phase extraction (more than 76% of the studied literature) and QuEChERS (quick, easy, cheap, effective, rugged, and safe), coupled with liquid chromatography–tandem-mass spectrometry, are commonly used for their determination. These methods offer high sensitivity, selectivity, and efficiency in identifying and quantifying pharmaceuticals in environmental samples. It is, therefore, essential that ongoing research is conducted in order to develop more efficient analytical methods and mitigation strategies to address pharmaceutical contamination in the environmental water effectively. It is also crucial that increased awareness and regulatory measures are put in place in order to minimize the environmental and human health risks associated with pharmaceutical pollutants. [ABSTRACT FROM AUTHOR]

Matrix solid-phase dispersion using a humate-based magnetic sorbent is proposed as an efficient method for the concentration of bisphenol A from fish muscular and hepatic tissue samples followed by the chromatography-mass spectrometry determination of an analyte prederivatized with acetic anhydride. Under the optimum concentration conditions (the stirring time is 10 min and the sorbent weight is 0.05 g), the recovery of bisphenol A upon single sorption reaches 85%. The percentage desorption exceeds 99% (the eluate is methanol, the time is 3 min, and the volume is 1 mL). The maximum enrichment factor is 718. The limit of the detection of bisphenol A is 0.15 μg/kg (on a dry basis) for muscular tissue and 0.25 μg/kg for liver. [ABSTRACT FROM AUTHOR]

The study of the reproduction characteristics of roses of the garden class Shrub, the defini-tion of the dependence of the hormonal determination of explant rhizogenesis on the con-centrations of phytohormones that are part of the nutrient medium, are relevant and has both scientific and practical interest. This study presents the results of studies of hormonal de-termination of rhizogenesis in explants of cultivars of roses of the garden class Shrub: Gärt-nerfreude, Lavender Dream, Pomponella, Red Cascade, Sommerabend cultivated in vitro on nutrient medium containing growth regulators. It has been established that of the nutrient medium modified by the addition of 0.2-1.0 mg/l α-naphthylacetic acid (α-NAA), the most effective was the medium with the content of α-NAA 0.5 mg/l, the content of macro- and microelements half of the Murashige and Skoog prescriptions, and a decrease in the sucrose content to 2.0%. On this medium, the frequency of rhizogenesis averaged 61.2% for the studied cultivars. Hormonal determination of rhizogenesis and efficiency of root formation in vitro in the Shrub rose regenerants depended on the genotype of the plant: cv. Lavender Dream (66.0%) and cv. Sommerabend (67.0%) had the highest rhizogenesis ability. The use of the universal growth regulator Humifield in combination with 0.5 mg/l α-NAA contribut-ed to an increase in the rooting rate of the studied rose cultivars up to 70.0-86.0%.

This article presents for the first time a new working electrode with a long service life— the bismuth-plated array of carbon composite microelectrodes for the simple, fast and sensitive determination of quercetin by adsorptive stripping voltammetry. The main experimental conditions were selected. The calibration graph was linear from 1 × 10−9 to 2 × 10−8 mol L−1 with an accumulation time of 60 s. The detection limit was equal to 4.8 × 10−10 mol L−1. The relative standard deviation for 2 × 10−8 mol L−1 of quercetin was 4.4% (n = 7). Possible interference effects resulting from the presence of other organic and surface active compounds and interfering ions were studied. The developed procedure was successfully applied to determine quercetin in pharmaceutical preparations and the spiked urine samples. [ABSTRACT FROM AUTHOR]

The effects of temperature, carbon source, nitrogen source, light, medium and pH on mycelial growth, sporulation and spore germination rate were studied. The results showed that pH 7 and total darkness were conducive to the mycelial growth, sporulation and spore germination of Alternaria alternata; 25 ℃ was optimum to mycelial growth, 25-30 ℃ was optimum to sporulation, and 20-30 ℃ was optimum to spore germination; the optimum carbon source for mycelial growth was soluble starch, the nitrogen source was yeast extract, KNO3 and peptone, the optimum carbon source and nitrogen source for sporulation were sorbitol and KNO3, respectively, and the optimum carbon source and nitrogen source for spore germination were lactose and NH4NO3, respectively; PSA, OA and PDA medium were suitable for mycelial growth, LB medium was suitable for sporulation, and OA medium was suitable for spore germination. The results provide a theoretical basis for clarifying the occurrence rules of walnut branch blight, and also provide a reference for the comprehensive control measures. [ABSTRACT FROM AUTHOR]

In this work, NiCo2S4 nanosheet-decorated Cu7S4 hollow microcubes were synthesized by electroless deposition and hydrothermal techniques for electrochemical determination of glucose in human serum. First, Cu2O cubes were synthesized at room temperature by electroless deposition, while the NiCo precursors (NiCo2O4 nanosheets) were grown using the hydrothermal process. Afterward, a Cu7S4–NiCo2S4 composite was synthesized via one-step vulcanization of Cu2O and NiCo2O4 using Na2S. The crystal structure, elemental valence state, and morphology of the synthesized Cu7S4–NiCo2S4 composite were investigated using X-ray diffraction, X-ray photoelectron energy spectroscopy, scanning electron microscopy, and transmission electron microscopy. Note that the hollow-structured Cu7S4 can not only serve as the substrate for NiCo2S4 nanosheets to enhance the specific surface area but also promote the electron transfer and improve the electrocatalytic activity of the Cu7S4–NiCo2S4 composite. By optimizing the experimental parameters of the applied potential, the amount of Cu7S4–NiCo2S4 composite, and the concentration of NaOH solution, the Cu7S4–NiCo2S4-modified glassy carbon electrode demonstrates a good linear relationship with glucose concentrations in the ranges of 0.002–0.3 and 0.3–20 mM, with sensitivities of 430 and 162 μA mM–1 cm–2, respectively. The detection limit is 0.4 μM (S/N = 3). The proposed sensor exhibits remarkable performance in detecting the glucose content in human serum, implying its immense practical potential. [ABSTRACT FROM AUTHOR]

The literature data on the use of triphenylphosphine in determining peroxide functional groups and individual oxygen-containing compounds in the composition of the products of oxidation reactions of organic compounds with molecular oxygen and/or peroxides were systematized and discussed. The causes and mechanisms of distortions of the results of analytical determinations were identified and possible ways of their elimination were suggested. [ABSTRACT FROM AUTHOR]

[Objectives] The purpose of this paper was to develop a method for the high-throughput determination of 8 sulfonamides, 3 tetracyclines, 2 quinolones and trimethoprim drug residues in pork and chicken tissues by colloidal gold immunochromatographic assay(GICA). [Methods] Sulfonamides, tetracyclines, quinolones and trimethoprim in animal muscle tissues were extracted by phosphate buffer and diluted by phosphate buffer with Tween 20, binding to colloidal gold-labeled monoclonal antibodies and inhibiting the binding of the antibodies to the antigen on the nitrocellulose membrane test line(T-line), which resulted in a change of the color of the T-line. The qualitative determination of poly-veterinary drug residues in the samples was made by comparing the color shades of the T-line and control line(C-line). [Results] This test optimized the key factors such as pH value, antibody addition, antigen encapsulation, Tween 20 addition and type of lyophilized protectant. The limit of detection for sulfonamides, tetracyclines, quinolones and trimethoprim was 50, 100, 50 and 35 μg·kg-1, respectively, and the sensitivity ≥97%, the false positive rate ≤2%, the false negative rate ≤3%, and the method was consistent with the results detected by the existing standard method. [Conclusions] The method was simple with high sensitivity, high precision, short detection time and good stability. It could be used for high-throughput rapid detection of multi-veterinary drug residues in animal muscle tissue. [ABSTRACT FROM AUTHOR]

Caste plasticity is an essential trait in social insects, and it facilitates the allocation of individuals in different tasks according to population demands in the colony (e.g. workers can become queens upon loss or death of their "original queen"). The process of caste determination can take place in immature stages (preimaginal) or through adult stages (imaginal). Neotropical social wasp tribe Epiponini has both types of caste determination process and is thus a fascinating group to study caste plasticity. We performed queen removal tests in five Epiponini species with preimaginal and imaginal caste determination to better understand caste plasticity and queen selection processes. Queen absence stimulates the establishment of new reproductive females in Chartergellus and Metapolybia (imaginal), while females in Protopolybia (preimaginal) attempt to lay eggs even in the presence of their "original queen". Contrary to what has been hypothesized, we found that age is not a predictive factor in the female's potential to become a queen. Caste flexibility seems to be a crucial trait which aids Epiponini tropical colonies to survive, as it allows the colony to replace lost workers and queens promptly until a new generation of wasps can emerge. Highlights: Epiponini wasps presented caste flexibility since workers of different ages could replace queens in the case of they lost. [ABSTRACT FROM AUTHOR]

It is difficult to analyze different concentrations of pharmaceutical active substances in dosage forms simultaneously, especially in formulations containing high amounts of excipients, on environmentally friendly principles without the need for any intervention. This study proposes a powerful analytical method for the simultaneous determination of L-ascorbic Acid and N-Acetyl Cysteine in an effervescent tablet using high performance liquid chromatography technique. In the study, it was aimed to reduce the use of toxic solvents/chemicals and waste emissions, to increase efficiency and to reduce the negative environmental consequences that may arise from them. The method was developed using a C18 (ACE-121-2546, 4.6 x 250 mm, 5 µm) column and a sodium dihydrogen phosphate buffer mobile phase. Detection wavelengths were taken as 210 and 240 nm while the flow rate was 1 mL/min. The linearity, accuracy and precision, selectivity, sensitivity, and robustness of the proposed method were validated using International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use Q2R criteria and its green assessment was validated by AGREE and AGREEprep applications. The linear range was taken as 0.1-100 µg/mL for both compounds analyzed in the developed method. The detection limit of the method was 0.02 and 0.04 µg/mL respectively for L-ascorbic Acid and N-Acetyl Cysteine. The recovery of the method was between 98.75%-102.20% and the accuracy and precision of the method for all compounds were 0.17% and 0.11% respectively. This new environmentally friendly method can be easily used by the chemical and pharmaceutical industries for regular analysis without any restrictions. [ABSTRACT FROM AUTHOR]

This study aimed to develop an electrochemical method for the electrochemical determination of bufexamac (BUF), an important anti-inflammatory drug. For this purpose, the electrochemical properties of BUF were elucidated using a glassy carbon electrode (GCE) and cyclic voltammetry. The electrochemical performance of BUF was examined by the differential pulse voltammetry (DPV) method. It was observed that the response of GCE to DBT was linear in the concentration range of 6.0 × 10-6 M and 1.0 × 10-4 M. The limit of detection (LOD) was found to be 2.64 × 10-8 M; The limit of quantification (LOQ) was calculated as 8.79 × 10-8 M. The dexketoprofen tromethamine (DEX), diclofenac (DIC), and ibuprofen (IBU) were used as model active compounds to illustrate the oxidation mechanism of BUF. A simple, rapid, and sensitive electrochemical method for quantitatively determining BUF in a commercial sample of human serum was developed and validated. The calibration curve was linear in the 8.0 × 10-6 - 1.0 × 10-4 M in the biological media. The LOD for the commercial sample of human serum was set at 1.59 × 10-7 M. The electrochemical response of BUF in the presence of interferent was evaluated. The data obtained from the study showed that the developed method can be used in sensitive and selective BUF determination. [ABSTRACT FROM AUTHOR]

Grounding necessitarianism (GN) is the view that full grounds necessitate what they ground. Although GN has been rather popular among philosophers, it faces important counterexamples: For instance, A = [Socrates died] fully grounds C = [Xanthippe became a widow]. However, A fails to necessitate C: A could have obtained together with B = [Socrates and Xanthippe were never married], without C obtaining. In many cases, the debate essentially reduces to whether A indeed fully grounds C–as the contingentist claims–or if instead C is fully grounded in A+, namely A plus some supplementary fact S (e.g. [Xanthippe was married to Socrates])–as the necessitarian claims. Both sides typically agree that A+ necessitates C, while A does not; they disagree on whether A or A+ fully grounds C. This paper offers a novel defence of the claim that, in these typical cases, unlike A+, A fails to fully ground C–thereby bringing further support to GN. First and foremost, unlike A+, A fails to fully ground C because it fails to contain just what is relevant to do so, in two distinct senses–explanatory and generative relevance. Second, going for A, rather than A+, as a full ground undermines not just grounding necessitarianism, but modally weaker views which even contingentists may want to preserve. [ABSTRACT FROM AUTHOR]

Living specimens of four species of ermine moths: Spindle Ermine Yponomeuta cagnagella Hübner, 1813, Apple Ermine Y. malinellus Zeller, 1838, Orchard Ermine Y. padella (Linnaeus, 1758 and Willow Ermine Y. rorrella (Hübner, 1796) (Lepidoptera: Yponomeutidae) are considered to be difficult or nearly impossible to distinguish from each other based on visual observations. Research and statistical analysis of forewing characteristics, measurements of forewing lengths and literature review result in a key for identification and descriptions of four prototypes, improving the ability to identify the species. This can lead to a significant improvement in identification, especially for the Willow Ermine and the Orchard Ermine, but does not provide 'absolute' certainty regarding the accuracy of identifications. [ABSTRACT FROM AUTHOR]

A composite based on Fe3O4 nanoparticles, graphene oxide, and a ionic liquid (1-butyl-3-methylimidazolium-2-carboxylate) is proposed as a sorbent for the extraction of bisphenol A (BPA) from bottom sediments by matrix solid-phase dispersion (MSPD). The saturation magnetization of the synthesized sorbent is 34 emu/g. Grinding of bottom sediments and subsequent grinding with a sorbent was carried out in a ball mill. Some stages of MSPD were partially automated, in particular, the procedures of magnetic separation, BPA desorption, and sorbent regeneration. The recovery of BPA under the experimentally selected conditions (sorbent mass 0.5 g, time required to grind the sorbent 5 min) was 94%. The sorbent can withstand four sorption-desorption cycles without a loss of sorption capacity. To purify the matrix from interferents, washing with n-heptane was proposed. Bisphenol A was determined by gas chromatography–mass spectrometry after derivatization with acetic anhydride. The analytical characteristics of the method were established using model samples of bottom sediments artificially contaminated with BPA. The limit of determination using the developed method is 0.1 μg/kg, the linearity range of the calibration curve is 0.3–12 μg/kg (r2 = 0.994). As real samples for analysis, we used bottom sediments selected near the discharge of wastewater treatment plants in the city of Voronezh (Voronezh River and Don River). The BPA concentration in bottom sediments is 3.83–6.52 μg/kg. [ABSTRACT FROM AUTHOR]

Much of what has recently been written about taxonomy has focused on negatives in the face of a heterogeneously defined taxonomic impediment. The current review takes a step back from the rhetoric to explicate the modern science of taxonomy with a new practical model, "the five 'D's": taxon discovery, delimitation, diagnosis, description, and specimen determination. Although individual taxonomists may focus more on some of these practices and less on others, taxonomy as a discipline requires all five. Each practice depends on the one prior and necessarily leads to and often overlaps with the one following. In fact, the first 'D'—taxon discovery—has its origin in the last, specimen determination, thereby closing a recursive loop of taxonomic progress. Hopefully users of taxonomy—almost all biologists—will appreciate a fresh perspective on a foundational science. Several recommendations are offered to biological researchers to account for the iterative improvement, and hence necessary change, in the taxonomy and nomenclature of their study organisms. [ABSTRACT FROM AUTHOR]

Dissipative behavior and final residue levels of difenoconazole, prochloraz, propiconazole, and pyraclostrobin in figs were investigated using field trials and laboratory assays. A three‐factor, three‐level orthogonal test was designed to optimize the pretreatment conditions of the method. A method was established using high‐performance liquid chromatography tandem mass spectrometry for the determination of difenoconazole, prochloraz, propiconazole, and pyraclostrobin residues in figs. The limit of quantification for all four targets in figs was 0.002 mg/kg. Difenoconazole, prochloraz, propiconazole, and pyraclostrobin are readily digestible pesticides in figs with half‐lives of 6.4, 6.2, 4.8, and 7.9 days, respectively. Residues of difenoconazole, prochloraz, propiconazole, and pyraclostrobin in figs were below the European Union established residue levels of 0.1, 0.03, 0.01, and 0.02 mg/kg, respectively, at day 7 after application. Pyraclostrobin, propiconazole, difenoconazole, and prochloraz were applied twice at doses of 75, 125, 150, and 200 mg a.i./kg at 7‐day intervals, and the residues of the four fungicides in figs were acceptable 7 days after the last application. Therefore, the safety interval can be set at 7 days for 70% difenoconazole‐prochloraz wettable powder and 40% pyraclostrobin‐propiconazole aqueous emulsion according to the protocol. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Faculty of Pharmacy of Ankara University / Ankara Üniversitesi Eczacilik Fakültesi Dergisi is the property of Ankara University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A voltammetric method for determining itopride hydrochloride (ITP) based on titration of the analyte with a solution of photogenerated iodine obtained by irradiation of an auxiliary solution containing potassium iodide and a mixture of sensitizers (nsodium eosinate:nuranine = 1:1) at pH 5.68 was developed. Stabilization of the current in the amperometric unit circuit indicated the reaction of the titrant with ITP was complete and provided control of the ITP content in the preparation by the change in the current strength because the iodine content in the solution was controlled by a voltammetric method. Further irradiation of the solution and measurement of the generation time required to replenish the lost titrant also allowed regulation of the ITP content in the preparation. The dependence of the analytical signal on the ITP concentration was linear in the range 8.0 – 40.0 mg. The calculated limits of detection (LD) and quantification (LQ) were 33.0 and 11.0 mg by varying the current and generation time, respectively. The developed method met requirements given in the manual on validation of bioanalytical methods, was easy to use, and did not require expensive equipment and reagents. Therefore, it could be recommended for routine control of drug quality parameters in any analytical laboratory. [ABSTRACT FROM AUTHOR]

Nowadays, the rapid improvements in the medical and pharmaceutical fields increase the diversity and use of drugs. However, problems such as the use of multiple or combined drugs in the treatment of diseases and insensible use of over-the-counter drugs have caused concerns about the side-effect profiles and therapeutic ranges of drugs and environmental contamination and pollution problems due to pharmaceuticals waste. Therefore, the analysis of drugs in various media such as biological, pharmaceutical, and environmental samples is an important topic of discussion. Electrochemical methods are advantageous for sensor applications due to their easy application, low cost, versatility, high sensitivity, and environmentally-friendliness. Carbon nanomaterials such as diamond-like carbon thin films, carbon nanotubes, carbon nanofibers, graphene oxide, and nanodiamonds are used to enhance the performance of the electrochemical sensors with catalytic effects. To further improve this effect, it is aimed to create hybrid platforms by using different carbon nanomaterials together or with materials such as conductive polymers and ionic liquids. In this review, the most used carbon nanoforms will be evaluated in terms of electrochemical characterizations and physicochemical properties. Furthermore, the effect of hybrid platforms developed in the most recent studies on electrochemical sensors will be examined and evaluated in terms of drug analysis studies in the last five years. [ABSTRACT FROM AUTHOR]

The rapid quantification of toxins in food and beverage products has become a significant issue in overcoming and preventing many life-threatening diseases. Aflatoxin-contaminated food is one of the reasons for primary liver cancer and induces some tumors and cancer types. Advancements in biosensors technology have brought out different analysis methods. Therefore, the sensing performance has been improved for agricultural and beverage industries or food control processes. Nanomaterials are widely used for the enhancement of sensing performance. The enzymes, molecularly imprinted polymers (MIP), antibodies, and aptamers can be used as biorecognition elements. The transducer part of the biosensor can be selected, such as optical, electrochemical, and mass-based. This review explains the classification of major types of aflatoxins, the importance of nanomaterials, electrochemical, optical biosensors, and QCM and their applications for the determination of aflatoxins. [ABSTRACT FROM AUTHOR]

Copyright of China Fiber Inspection / Zhongguo Xian-Jian is the property of China Fiber Inspection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The determination of arsenic content in phosphorus pentoxide by atomic fluorescence spectroscopy method was studied, and the acid medium, acidity, reducing agent concentration, pre reducing agent, and masking agent were determined. The results indicate that the method has good linearity in the range of 1.0~50.0 /, ig/L, the correlation coefficient is r>0.999, the detection limit is 0.06 µg/L, quantification limit is 0.21 µg/L. The relative standard deviation (RSD) of the 8 sample analysis results is 1.94%, and the spiked recovery rate are 92.87%~101.30%. The test results show no significant difference from the DDTC silver salt method, and this method is a reliable method for detecting arsenic content in phosphorus pentoxide, because it is more convenient and less reagent used. [ABSTRACT FROM AUTHOR]

Copyright of Alauddin Law Development Journal is the property of Alauddin Law Development Journal (ALDEV) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the processing of construction waste, the sorting of the delivered mixtures is one of the decisive process steps in order to produce recyclates that can be reused. In the fine‐grain range, there is a lack of suitable processes for this. A procedure that has not been investigated so far is to separate concrete‐mortar‐brick mixtures on the basis of the magnetic susceptibility. Based on measurements of the susceptibility, sorting experiments were carried out using a rare earth roll magnetic separator. The positive results of the experiments described here call for further investigation of the performance of the sorting method. [ABSTRACT FROM AUTHOR]

A sensitive, easy, and low-cost method used in the determination of pure forms of losartan and mebeverine hydrochloride, also in pharmaceutical preparations with derivative spectrometry using UV-Vis technology. This method depends on measuring the first derivative of the spectrum using zero cross, peak to base line, and peak area. The linear range of concentrations used was equal to 2–14 ppm for losartan, whereas for mebeverine hydrochloride it was equal to 2–16 ppm in a mixture. For losartan, in the presence of mebeverine hydrochloride, 12 ppm by utilizing peak to baseline correlation coefficients 0.9984, 0.9994, and peak area 0.9972, whereas for mebeverine hydrochloride in the presence of losartan, 12 ppm by utilizing peak to fundamental correlation coefficients 0.9952, 0.9966, 0.9957, and peak area 0.9970, 0.9971, 0.9968, 0.9971. The limit of detection for each drug, losartan and mebeverine hydrochloride, is equal to 0.0113 ppm. The accuracy and precision of the method were estimated by calculating relative standard deviation (%RSD) values less than 3% while maintaining a recovery percentage of acceptable value. The proposed method proved effective and efficient at estimating both losartan and mebeverine hydrochloride, in the presence of the other in a mixture of the two without interference, despite the closeness of their spectral absorption peaks. There are no other more accurate methods for estimating the two in a mixture than the proposed method. The proposed method is considered one of the most direct and economical methods that do not require reagents or additional materials for conducting reactions and studying the optimal conditions for those interactions. Thus, it is considered one of the green chemistry techniques that reduce the use of chemicals and reagents in the process of estimating these drugs in a mixture and in a shorter period of time. The proposed method can be used to estimate the different properties in a mixture of the two compounds whose absorption spectra are close. [ABSTRACT FROM AUTHOR]

A method for obtaining effervescent tablets, consisting of magnetic carbon, tartaric acid, sodium carbonate and sodium bicarbonate, and their use for the adsorption of dichlorophenoxycarboxylic acids (DCPA)—2,4-dichlorophenoxyacetic, 2,4-dichlorophenoxypropionic and 2,4-dichlorophenoxybutyric acids and their metabolites—2,4-dichlorophenol and 4-chlorophenol is proposed. The tablets are immersed in an analyzed solution with a neutral reaction medium. To analyze soils, extraction with an alkali solution followed by the neutralization of the extract is carried out. After CO2 separation is completed, the sorbent is removed with a neodymium magnet and the analytes are desorbed with acetone. The acetone extract is evaporated under a stream of nitrogen, and the concentrate is analyzed by gas chromatography–mass spectrometry. The method was tested on model systems—samples of river water and typical chernozem, which were artificially contaminated with DCPA and chlorophenols (CP). In analyzing river waters, the limits of determination for DCPA are 0.7–0.9 μg/L, for CP—40 ng/L. In soils, the limit of detection is 3–4 and 0.1 μg/kg for DCPA and CP, respectively. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles have been widely used in various fields of study. Due to the increasing use of these nanoparticles, it is important to develop sensitive methods for measuring these nanoparticles in real samples. In this research, a method was developed to measure magnetite nanoparticles using microfluidics science and paired emitter-detector diode-based photometry. The basis work of the designed system is based on the magnetic preconcentration of nanoparticles inside the microchip, dissolution by acid, and creation of a signal through the formation of an iron-thiocyanate complex. The validation results of the method showed that the linear range of the method is from 1.0 to 6.0 ppm with appropriate accuracy (recovery percentages: 104.0% and 95.6%) and precision (coefficient of variation: 0.17% and 0.15%), which is satisfactory for measuring trace amounts of magnetic nanoparticles. The limits of detection and quantification were obtained as 0.3 and 0.9 ppm, respectively. Compared to previously reported methods, the developed method provides higher sensitivity and simpler instrumentation of lower analysis cost by the use of a microfluidic chip for magnetic preconcentration of magnetic nanoparticles, washing, dissolution, and photometric determination. [ABSTRACT FROM AUTHOR]

The study included estimation of glutathione (GSH) as an important biomarker using turbidimetric method based on reaction of GSH with Ce(IV) in acidic medium to form turbid solution. More than twenty metal ions were used to test their interaction with GSH in acidic medium, it was obtained that only Ce(IV) forms turbid product. Instead of using turbidimeter to conduct measurements, a single beam spectrophotometer was used for this purpose. The measurements were studied at three wavelengths via 500, 700 and 900nm, but a near infrared wavelength, i.e. 900nm, shows the best results. In addition, the effect of temperature, time, type of acid, sequence addition as an optimum conditions required for the product to form were studied. Then the effect of the interferences was studied at two concentrations. A calibration curve in µg.mL-1 was constructed and its trending lies on points of concentrations ranged from 20 to 180µg.mL-1 with a correlation coefficient of 0.9994, and detection limit of 0.0005 µg.mL-1 and slope is (0.0014). The analytical method was applied on samples of human blood serum. The obtained results were compared with the results of the referenced (kit) method. The results obtained by the method followed, some of them were close and the others were far. [ABSTRACT FROM AUTHOR]

A new high‐performance liquid chromatography (HPLC) method was applied for the quantification of the active substance of tofacitinib. Analysis was performed on a Chromasil 100 C18 (100.0 × 4.0 mm, 3.5 μm) stationary phase. The mobile phase consisted of acetonitrile:0.2% phosphoric acid in water (12:88, v/v). The prepared sample (20.0 μL) was injected into the system. A detection wavelength of 285.0 nm was chosen for the compound, and the flow rate was 0.8 mL/min. The experiment was completed in 5.0 min. The analysis temperature was set to 40.0°C. The method was evaluated using green chemistry. The method was validated according to the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. For linearity studies calibration curves were constructed in the range of 10.0–200.0 μg/mL. The recovery values were calculated at 97.66% and 105.68%. The method developed for the analysis of the active substance had a short analysis time and was cost‐effective. It is an environmentally friendly method due to the mobile phase content used. The technique can be used in laboratory analysis and bioequivalence experiments. [ABSTRACT FROM AUTHOR]

Lutein in human breast milk plays an important role in the development of vision and cognitive function in infants. In this study, ultra-high performance liquid chromatography tandem mass spectrometry was used to determine the composition and contents of lutein and lutein esters in human breast milk collected at different ages for giving childbirth and lactation stages. Finally, lutein and 16 lutein esters in human breast milk were qualitatively and quantitatively analyzed. A strong positive correlation was found between lutein and lutein esters contents in human breast milk (Pearson correlation coefficient was 0.721). The contents of lutein and lutein esters in human breast milk in the age-appropriate group (childbith age<35 years) was similar to that of the older age group (childbirth age ≥35 years), and the difference between the two was insignificant (P>0.05), indicating that the age for giving childbirth had little effect on the contents of lutein and lutein esters in human breast milk. The contents of lutein and lutein esters decreased gradually with the extension of the lactation period, and the contents of both in colostrum were the highest, with the average content of lutein reaching 183.78 µg/L and the average content of lutein esters reaching 45.89 µg/L. There were 10, 14 and 6 kinds of lutein esters detected in the colostrum, transitional milk and mature milk, respectively, with the content of lutein palmitate-stearate being the highest throughout the whole lactation period, followed by lutein distearate. The research results can provide certain experimental and theoretical bases for the research of human milk composition and the research and development of infant formula foods. [ABSTRACT FROM AUTHOR]

With the rapid development of industrialization, the problem of concentration determination based on the copper production process has been widely concerned, and the accurate determination of high-concentration copper ions (Cu2+) is of great significance for enterprise production, resource utilization, and pollution prevention. The characteristics of different spectrophotometric methods for the determination of Cu2+ are discussed, and it is found that these methods are suitable for the determination of trace or low concentration of Cu2+ (0.5 μg/L–5 mg/L), whereas for the determination of high Cu2+ concentration pre-treatments such as dilution, complexation, and coloring are required. In this study, a method based on ultraviolet-visible spectroscopy (UV-Vis) combined with partial least squares regression analysis (PLS) was proposed for the determination of high copper ions (>100 mg/L), which performs rapid and accurate determination of high Cu2+ concentration by preprocessing and feature extraction of UV-Vis spectral data, followed by model construction with PLS analysis, which is easy to operate and applicable to a wide range of concentrations. The correlation coefficient (R2), mean relative error (MRE), and root mean square error (RMSECV) of the model prediction of Cu2+ concentrations were 0.99946, 0.006343, and 11.237 mg/L, respectively, indicating that the accuracy of the model prediction is very high. This study not only provides an efficient method for the precise determination of high Cu2+ concentration but also enables the simultaneous determination of Cu2+, Co2+, and Ni2+ ions, which provides a new technical means for environmental monitoring and pollution prevention. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)