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Exploring tazarotene, a third-generation retinoid for potential hand osteoarthritis treatment, this study presents the development and validation of an ultra-performance liquid chromatography with quadrupole detector mass spectrometry (UPLC-QDa) method for the simultaneous quantification of tazarotene and tazarotenic acid, its active metabolite, in porcine skin. Method development involved a design-of-experiments approach for chromatographic optimization of gradient steepness, organic solvent volume, column temperature, capillary voltage, flow rate, and cone voltage. Central composite orthogonal design was used to optimize peak area, peak width, retention time, and resolution. Validation was performed in accordance with U.S. Food and Drug Administration guidelines. The method was linear over the concentration range of 0.4–18,750 ng/mL for tazarotene and 13.3–12,500 ng/mL for tazarotenic acid, with r2 values of ≥0.99. Chromatographic analysis demonstrated acceptable accuracy and precision (<15%), and stability tests confirmed the analytes' stability under various conditions. This validated method offers a reliable and accurate approach for the simultaneous analysis of tazarotene and tazarotenic acid, facilitating further research into their therapeutic applications for hand osteoarthritis. [ABSTRACT FROM AUTHOR]

Vitamin K consumption needs to be monitored in people taking warfarin since it can impact the anticoagulation response. Vegetables are the primary nutritional source of Vitamin K1, in the form of Vitamin K1. The aim of this study was to measure the level of Vitamin K1 in various vegetables that were commercially sold in three major Bandung markets and were ingested by patients using warfarin at Hasan Sadikin Central General Hospital Bandung. High-performance liquid chromatography with an ultraviolet detector set at 245 nm was the analytical technique. One hundred percent methanol was used as the mobile phase, and it was isocratically eluted at a flow rate of 0.6 mL/min with a T3 column maintained at 25°C. The results indicated that the following Vitamin K1 levels were found in lettuce: 38.4391 ± 15.2650–64.4419 ± 19.0315 µg/100 g, in napa cabbage: 56.7445 ± 0.1569–273.2828 ± 8.3061 µg/100 g, in cabbage: 27.9531 ± 1.7487–217.0457 ± 7.2201 µg/100 g, and in spinach: 305.2868 ± 3.3058–970.7098 ± 14.1167 µg/100 g. The highest Vitamin K1 level was in spinach and the lowest was in lettuce. [ABSTRACT FROM AUTHOR]

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a devastating invasive pest recently introduced in India in 2018. The fall armyworm infestation has significantly impacted maize cultivation in the country. Identifying the host plant volatiles (kairomones) that are attractive to S. frugiperda from its highly preferred host plant, i.e. maize will help developing eco-friendly management strategies against this nefarious pest. Gas chromatography electroantennogram detector (GC-EAD) analysis revealed that a total of 18 compounds in maize headspace volatiles and 17 in maize leaf extract elicited an antennal response in female moths of S. frugiperda. Olfactometer bioassays of GC-EAD active plant volatile compounds revealed that heptanoic acid, 2,5-ditert butyl-1,4-benzoquinone and n-hexadecane were the most preferred plant volatile compounds and 50: 50 ratio blend of heptanoic acid and 2,5-ditert butyl-1,4-benzoquinone was found to be the most attractive kairomone blend for S. frugiperda. [ABSTRACT FROM AUTHOR]

This study aimed to assess the presence of ochratoxin A (OTA) residues in the blood serum of slaughtered pigs in Greece. Samples were obtained from 1695 healthy slaughtered pigs originating from 113 different farms located in 21 geographic regional units in 8 different geographic regions of Greece and were analyzed using an immunosorbent assay (ELISA) and high-performance liquid chromatography with fluorescence detector (HPLC-FD). OTA contamination assessment showed that 782 (46.1%) and 1233 (72.7%) samples were OTA-positive, with a concentration range of 0.20–5.38 μg/L and 0.15–5.96 µg/L according to ELISA and HPLC-FD analysis, respectively. Also, 88 (77.9%) and 108 (95.6%) of farms were found to be OTA-positive by ELISA and HPLC-FD analysis, respectively. The highest OTA serum positivity rate (>98%) and toxin level (5.96 µg/L) determined by HPLC-FD were observed in the Thessaly region, whereas a high prevalence of up to 100% (range 75–100%) was found on farms in the Crete Island region. The detection of OTA in the serum of slaughtered pigs in different regions in Greece poses a risk for animal and human health and highlights the need for constant OTA monitoring in the swine industry and pork meat production facilities. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA), which is one of the most important mycotoxins in terms of human health, can be found in cereal products such as bread, "bazlama" (traditional flatbread), and pita bread, as well as cereals such as wheat, barley, and corn. This study aimed to determine the effect of different fermentation times, baking, and storage for various periods on the presence of OTA in sourdough bazlama. Bazlama flour was contaminated with OTA concentrations of 5 and 10 μg/kg. After two different fermentation times (1.5 and 3 h), baking at 300 ± 5°C, and storage at room temperature (25 ± 2°C) for 0, 5, and 10 days, the change in OTA levels of bazlama samples was determined by the high‐performance liquid chromatography with fluorescence detector (HPLC‐FLD) method. The effect of different storage periods on the presence of OTA is insignificant. Although a general decrease in OTA level has been determined, it has been found that long‐term fermentation (at least 3 h) was more effective, especially in flours with a high concentration (10 μg/kg) of OTA contamination. It has been determined that bazlama made from contaminated flours with OTA levels of 5 and 10 μg/kg contained OTA levels exceeding 3 μg/kg when long‐term fermentation was not used. This is the maximum permitted limit set by the Turkish Food Codex and the European Commission, indicating that it is not suitable for consumption in this position. [ABSTRACT FROM AUTHOR]

Simple Summary: Menbutone is a drug that increases hepato-digestive secretions and has been used for more than 50 years in Europe to treat a wide number of digestive disorders in livestock and dogs. However, despite this use, little is known about its pharmacokinetics, more specifically in cattle. This work contributes to a better knowledge of the pharmacokinetics of menbutone when administered intravenously and intramuscularly to cattle (12 Holstein calves), being the first study to describe it in this animal species. After intravenous administration, the drug showed a moderate volume of distribution and a fast elimination from the body. After intramuscular administration, menbutone exhibited quick and high absorption. Menbutone is a choleretic agent currently used in Europe to treat digestive disorders in livestock and dogs. Pharmacokinetic parameters were established in 4-month Holstein calves after intravenous (IV) and intramuscular (IM) administration. The drug was administered to 12 animals (10 mg/kg) for both IV and IM routes following a crossover design. Plasma samples were collected at various time points over 24 h and analyzed by reverse-phase high-performance liquid chromatography with a photodiode-array detector, following a method validated according to European Medicines Agency guidelines. Pharmacokinetic parameters were calculated using compartmental and non-compartmental methods. Menbutone followed a two-compartment open model after IV injection, with a total clearance (Cl) of 71.9 ± 13.5 mL/h/kg, an elimination half-life (t½β) of 4.53 ± 2.45 h, and a volume of distribution at steady-state (Vss) of 310.4 ± 106.4 mL/kg. Non-compartmental elimination half-life (t½λ) was 4.2 ± 1.1 h. After IM administration, drug pharmacokinetics was best described by a one-compartment open model. The peak plasma concentration (Cmax) was 15.1 ± 4.3 µg/mL; the time to reach Cmax (tmax), 1.66 ± 0.55 h; and the mean absorption time (MAT), 2.50 ± 1.42 h. Absorption was high, with a fraction of the dose absorbed (F) of 83.5 ± 22.4%. Menbutone was rapidly eliminated from plasma for both routes of administration, with a fast and high IM bioavailability. [ABSTRACT FROM AUTHOR]

Summary: The present study investigated the volatile and sensory profiles and antioxidant activity of 1,8‐cineole type Niaouli essential oil from Madagascar for which limited information is reported in literature. The volatile compounds were identified by Gas chromatography–mass spectrometry and semi‐quantitative results were obtained by Gas chromatography with a flame‐ionisation detector; the odour descriptors were determined by a trained panel using a Quantitative Descriptive Analysis. The antioxidant activity was determined, too. Several volatiles, most of these here firstly, have been identified; 1,8‐cineole (eucalyptus‐like) prevailed, followed by viridiflorol and (E)‐nerolidol. 'Eucalyptus‐like, fresh‐mint, woody, sweet‐floral and spicy' odour descriptors have been defined. Volatiles resulted in agreement with the odour descriptors. The data allowed to characterise the Niaouli essential oil; considering its volatile composition, pleasant sensory notes and antioxidant activity the 1,8‐cineole type Niaouli essential oil from Madagascar could be considered a promising flavouring agent and natural preservative in the food industry. [ABSTRACT FROM AUTHOR]

In this study, a magnetic porous polymer composite with both hydrophilic and hydrophobic groups was synthesized for magnetic solid phase extraction (MSPE) of milk substrates. Optimization was conducted on various parameters, including adsorption dose, solution pH, adsorption time, and some elution conditions. Coupled with a high-performance liquid chromatography fluorescence detector, a novel MSPE method for determination of norfloxacin (NFX), ciprofloxacin (CIP), and enrofloxacin (ENR) in milk was developed based on magnetic metal organic framework polystyrene polymer (Fe3O4@MOF@PLS) as adsorbent. The Fe3O4@MOF@PLS exhibited significantly improved adsorption performance compared to MOF and PLS. Under optimized experimental conditions, the method exhibited good linearity for the three fluoroquinolones (FQs) in the range of 0.5–1000 μg/kg, with limit of detections (LODs) ranging from 0.21 to 1.33 μg/kg, and limit of quantitations (LOQs) from 0.71 to 4.42 μg/kg. The relative standard deviation (RSD) for the three FQs were 3.4–8.8%. The recoveries of three FQs in milk samples ranged from 84.2% to 106.2%. This method was successfully applied to the detection of three FQs in 20 types of milk, demonstrating its simplicity, speed, and effectiveness in analyte enrichment and separation. The method presented advantages in adsorbent dosage, adsorption time, LODs, and LOQs, making it valuable for the analysis and detection of FQs in milk. [ABSTRACT FROM AUTHOR]

This study investigates the impact of changing parameters on the photocatalytic degradation of carbofuran (CBF) using laser-treated TiO2 nanotube arrays on a Ti mesh under simulated sunlight irradiation and assessing toxicity during photocatalytic degradation. Various parameters, including the stirring effect, light intensity, initial CBF concentration, and variation in the active surface area of laser-treated TiO2 photocatalysts, were examined to determine their impact on degradation efficiency. The photodegradation kinetics were monitored using ultra-performance liquid chromatography with a PDA detector (UPLC-PDA) and UV-Vis spectrophotometry, while mineralization was assessed by a total organic carbon (TOC) analyzer. The photocatalytic degradation of CBF is enhanced by an increase in the active surface area of the TiO2 photocatalyst, light intensity, and the introduction of stirring, but it decreases with an increase in the initial concentration of CBF. The toxicity assessments revealed that the cytotoxicity of CBF initially increased during the degradation process but decreased after further treatment, indicating the formation and subsequent breakdown of toxic intermediates. The phytotoxicity test showed that longer degradation times resulted in higher toxicity to plant growth. This study provides new insights into the photocatalytic degradation of CBF with TiO2, the importance of parameter optimization for more efficient treatment, and the use of toxicity tests to confirm the success of the photocatalytic process. [ABSTRACT FROM AUTHOR]

In order to establish a simple method for detecting acrylamide in food, this article optimizes the determination conditions, sample and processing conditions using highperformance liquid chromatography ultraviolet detector. The research results show that, the samples defatted by hexane, ultrasonic extraction in chloroform. The analytes were isolated by reversed phase high performance liquid chromatography on a C18(4.6x250mm, 5μm) column and eluted with 5% methanol aqueous solution at a flow rate of 0.8mL/min. The detection wavelength was 210 nm, Quantitative analysis method was external standard method. The experimental results indicated that the linearity of the calibration curve was good in the range of 0.2μg/ml~2.5μg/ml (r=0.9991), and the recoveries of acrylamide from spiked samples by this method were within 87.6%~97.8% (n=5). The method was simple, accurate, reliable and suitable for the determination of acrylamide in potato chips, instant noodles, biscuits, bread and other starchy foods. Compared with traditional methods, this method does not rely on expensive Mass spectrometry detection equipment and is easily adopted by most laboratories, which is conducive to its promotion and application in the food testing industry. [ABSTRACT FROM AUTHOR]

In the current study, chromatographic and in silico techniques were applied to investigate the biotransformation of ethyl 5-(4-bromophenyl)-1-(2-(2-(2-hydroxybenzylidene) hydrazinyl)-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate (11b) in hepatocytic media. The initial chromatographic procedure was based on the employment of the conventional octadecyl stationary phase method for estimation of the chemical stability. Subsequently, a novel and rapid chromatographic approach based on a phenyl–hexyl column was developed, aiming to separate the possible metabolites. Both methods were performed on a Dionex 3000 ThermoScientific (ACM 2, Sofia, Bulgaria) device equipped with a diode array detector set up at 272 and 279 nm for analytes detection. An acetonitrile: phosphate buffer of pH 3.5: methanol (17:30:53 v/v/v) was eluted isocratically as a mobile phase with a 1 mL/min flow rate. A preliminary purification from the biological media was achieved by protein precipitation with methanol. A validation procedure was carried out, where the method was found to correspond to all ICH (Q2) and M10 set criteria. Additionally, an in silico-based approach with the online server BioTransformer 3.0 was applied in an attempt to predict the possible metabolites of the title compound 11b. It was hypothesized that four CYP450 isoforms (1A2, 2C9, 3A4, and 2C8) were involved in the phase I metabolism, resulting in the formation of 12 metabolites. Moreover, docking studies were conducted to evaluate the formation of stable complexes between 11b and the aforementioned isoforms. The obtained data indicated three metabolites as the most probable products, two of which (M9_11b and M10_11b) were synthesized by a classical approach for verification. Finally, liquid chromatography with a mass detector was implemented for comprehensive and summarized analysis, and the obtained results revealed that the metabolism of the 11b proceeds possibly with the formation of glucuronide and glycine conjugate of M11_11b. [ABSTRACT FROM AUTHOR]

The content and composition of volatile aroma compounds in strawberries of the Ducat, Honey and Polka varieties were studied using GCMS analysis. To identify volatile compounds, an Agilent Technologies 6890 chromatograph with a 5973 mass spectrometric detector and a DB-5 chromatographic capillary column (inside diameter 0.25 mm and length 30 m) was used. Esters (12.8–41.8%), aldehydes (5.9–15.9%), ketones (8.7– 35.6%), furanones (22.7–24.4%), organic acids (2.47–21.85%), aroma compounds, lactones, terpenic compounds and alkanes were identified in the aroma. It was found that the aroma of strawberries of the Polka variety is presented by ethyl butanoate (30.7%), 2,5-dimethyl-4-methoxy-3(2H)- furanone (mesifurane) (19.9%), trans-2-hexenal (15.6%), acetoin (8.7%) and 2,5-dimethyl-4-hydroxy-3(2H)-furanone (3.7%). Ducat berries contain – acetoin (35.7%), 2,5-dimethyl-4-methoxy-3(2H)-furanone (mesifurane) (19.8%), trans-2-hexenal (11.3%), ethyl butanoate (10.1%) and 2,5- dimethyl-4-hydroxy -3(2H)-furanone (4.4%). The main aroma compounds of Honey berries are 2,5-dimethyl-4-methoxy-3(2H)-furanone (mesifurane) (19.1%), ethyl butanoate (14.1 %), hexanoic (caproic) acid (9.5%), acetoin (8.2 %), trans-2-hexenal (5.3 %), hexadecanoic acid (5.1%), 2,5-dimethyl-4- hydroxy-3(2H)-furanone (3.4%). In terms of aroma activity in berries, 2,5- dimethyl-4-methoxy-3(2H)-furanone (mesifurane) and 2,5-dimethyl-4- hydroxy-3(2H)-furanone (furaneol) prevail, with slightly lower activity of ethyl 2-methylbutanoate, ethyl butanoate and trans-2-hexenal. It has been proven that the aroma of strawberries grown in the Right-Bank ForestSteppe of Ukraine is most characterised by sweet, caramel tones, while fruit and green tones are less pronounced. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia 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.)

Sulfur hexafluoride (SF6), which survives in the atmosphere for an extremely long period of time, is the most potent greenhouse gas regulated under the Kyoto Protocol. So, the accurate monitoring of atmospheric SF6 plays an important role in the study of the control policies for reducing greenhouse gas emissions. The instruments for SF6 measurement are typically calibrated using certified reference materials. The concentrations of the commercially available SF6 reference materials usually have a broad range, from 1 μmol/mol to 6000 μmol/mol. Some characteristics including sensitivity, linear range, relative standard deviation, and accuracy are crucial for the determination of SF6 in such a broad concentration range. Therefore, the selection of a proper detector for the accurate determination of SF6 with such a broad range is extremely important to establish a gas chromatography (GC) method for developing SF6 reference materials. In this paper, several typical GC methods with different detectors, including a thermal conductivity detector (TCD), a pulsed discharge helium ionization detector (PDHID), and a flame photometric detector (FPD), were carefully established for the accurate determination of SF6 with different concentrations. The results show that an FPD detector has a relatively narrow linearity range, thus a quadratic equation should be established for building a calibration curve. The PDHID and TCD have good linearity with coefficients of 1.0000 in the concentration range of 10–100 μmol/mol (using a PDHID), and 100–1000 μmol/mol (using a TCD), respectively. Further considering the measurement errors of indication results, the PDHID is suitable for SF6 measurement when the concentrations are below 100 μmol/mol, whereas the TCD is suitable for SF6 measurement when the concentrations are over 100 μmol/mol. These results provide useful guidance in choosing an appropriate GC detector for the accurate determination of SF6, which are especially very helpful for developing SF6 reference materials. [ABSTRACT FROM AUTHOR]

This review highlights the advantages of high-precision liquid chromatography with an electrochemical detector (HPLC-ECD) in detecting and quantifying biological samples obtained through intracerebral microdialysis, specifically the serotonergic and dopaminergic systems: Serotonin (5-HT), 5-hydroxyindolacetic acid (5-HIAA), 3,4-dihydroxyphenylacetic acid (DOPAC), dopamine (DA), 3-metoxytryptamin (3-MT) and homovanillic acid (HVA). Recognized for its speed and selectivity, HPLC enables direct analysis of intracerebral microdialysis samples without complex derivatization. Various chromatographic methods, including reverse phase (RP), are explored for neurotransmitters (NTs) and metabolites separation. Electrochemical detector (ECD), particularly with glassy carbon (GC) electrodes, is emphasized for its simplicity and sensitivity, aimed at enhancing reproducibility through optimization strategies such as modified electrode materials. This paper underscores the determination of limits of detection (LOD) and quantification (LOQ) and the linear range (L.R.) showcasing the potential for real-time monitoring of compounds concentrations. A non-exhaustive compilation of literature values for LOD, LOQ, and L.R. from recent publications is included. [ABSTRACT FROM AUTHOR]

Gas chromatography (GC) is a versatile analytical technique widely employed for the determination of various compounds, including sulfur hexafluoride (SF6). SF6 is a potent greenhouse gas and its accurate measurement is crucial for environmental monitoring and industrial applications. Different detectors in GC offer varying sensitivity, selectivity, and detection limits, affecting the precision and accuracy of SF6 quantification. This article provides a comprehensive evaluation of different GC detectors for the precise determination of SF6, highlighting their advantages, limitations, and applicability. [ABSTRACT FROM AUTHOR]

In this work, a sensitive analytical method based on packed-nanofiber solid-phase extraction (PFSPE), after derivatization with trichloroacetic acid and high-performance liquid chromatography with a fluorescence detector (HPLC-FLD), has been established for the determination of aflatoxins (AFs) in milk. Polystyrene polymeric multi-walled carbon nanotube (PS-MWCNT/OH) composite nanofibers were fabricated by electrospinning and used to prepare homemade extraction columns. The extraction efficiency of the HPLC-FLD analysis method was sufficiently investigated and validated. After the implementation of optimal conditions, all of the analytes were separated efficiently and the components of the milk matrix did not disturb the determination. The obtained linear ranges of the calibration curves were 0.2–20 ng/mL for AFTB1 and AFTG2, 0.1–10 ng/mL for AFTB2, and 0.4–40 ng/mL for AFTG1. The recoveries ranged between 80.22% and 96.21%. The relative standard deviations (RSDs) for the intra-day and inter-day results ranged from 2.81–6.43% to 3.42–7.75%, respectively. Generally, 11 mg of sorbent and 200 μL of elution solvent were used to directly extract all of the AFs from the milk matrix. Reported herein is the first utilization of PS-MWCNT/OH-PFSPE HPLC-FLD to simultaneously analyze the occurrence of aflatoxins in milk. [ABSTRACT FROM AUTHOR]

Detectors in gas chromatography (GC) are unique in all analytical science. The detector performs several difficult functions that make sensitive and selective analysis possible. In this instalment, we will explore the challenges involved in detecting the effluent from a capillary gas chromatographic column, and summarize the many detector options. We will then consider basic ideas and tasks that allow detectors to function properly. Finally, we will examine some specific troubleshooting and preventative maintenance tips for common detectors. We will see that, with some simple preventative thinking and action, detectors in gas chromatography can provide excellent sensitivity and selectivity for years of use. [ABSTRACT FROM AUTHOR]

Gas Chromatography (GC) is a versatile analytical technique widely employed for the determination of various compounds, including Sulfur Hexafluoride (SF6). SF6 is a potent greenhouse gas and its accurate measurement is crucial for environmental monitoring and industrial applications. Different detectors in GC offer varying sensitivity, selectivity and detection limits, affecting the precision and accuracy of SF6 quantification. This article provides a comprehensive evaluation of different GC detectors for the precise determination of SF6, highlighting their advantages, limitations and applicability. [ABSTRACT FROM AUTHOR]

The mastic tree, scientifically known as Pistacia lentiscus, which belongs to the Anacardiaceae family, was used in this study. The aim of this research was to analyze the chemical composition of this plant and assess its antioxidant and antibacterial properties using both laboratory experiments and computer simulations through molecular docking, a method that predicts the binding strength of a small molecule to a protein. The soxhlet method (SE) was employed to extract substances from the leaves of P. lentiscus found in the eastern region of Morocco. Hexane and methanol were the solvents used for the extraction process. The n-hexane extract was subjected to gas chromatography-mass spectrometry (GC/MS) to identify its fatty acid content. The methanolic extract underwent high-performance liquid chromatography with a diode-array detector (HPLC-DAD) to determine the presence of phenolic compounds. Antioxidant activity was assessed using the DPPH spectrophotometric test. The findings revealed that the main components in the n-hexane extract were linoleic acid (40.97 ± 0.33%), oleic acid (23.69 ± 0.12%), and palmitic acid (22.83 ± 0.10%). Catechin (37.05 ± 0.15%) was identified as the predominant compound in the methanolic extract through HPLC analysis. The methanolic extract exhibited significant DPPH radical scavenging, with an IC50 value of 0.26 ± 0.14 mg/mL. The antibacterial activity was tested against Staphylococcus aureus, Listeria innocua, and Escherichia coli, while the antifungal activity was evaluated against Geotrichum candidum and Rhodotorula glutinis. The P. lentiscus extract demonstrated notable antimicrobial effects. Additionally, apart from molecular docking, other important factors, such as drug similarity, drug metabolism and distribution within the body, potential adverse effects, and impact on bodily systems, were considered for the substances derived from P. lentiscus. Scientific algorithms, such as Prediction of Activity Spectra for Substances (PASS), Absorption, Distribution, Metabolism, Excretion (ADME), and Pro-Tox II, were utilized for this assessment. The results obtained from this research support the traditional medicinal usage of P. lentiscus and suggest its potential for drug development. [ABSTRACT FROM AUTHOR]

BACKGROUND: As the main source of iodine intake, water is of practical significance to detect the content of iodide accurately. At present, the common methods for the analysis of iodide in water samples include ion chromatography, gas chromatography, colorimetry, spectrophotometry. The analysis results of different methods can be affected by the actual sample matrix and experimental conditions. Our project team organized 38 laboratories to determine the content of iodide in natural water samples by ion chromatography, starch spectrophotometry, catalytic reduction spectrophotometry, and inductively coupled plasma-mass spectrometry (ICP-MS), the results showed that there were significant differences among the measured values by different methods, and the data were obviously dispersed. OBJECTIVES: To discuss the reasons for the differences between the results of different methods and give suggestions on the selection of iodide analysis methods under different conditions, based on the principles and conditions of each method. METHODS: Four analysis methods, including ion chromatography, starch spectrophotometry, catalytic reduction spectrophotometry, and ICP-MS, were used to determine the content of iodide of the groundwater sample by 38 laboratories. High performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP)MS) was used to determine the content of iodide by our own laboratory. RESULTS: (1) HPLC-ICP-MS can be used to effectively separate iodide and iodate ions in water samples. Through the quality control of the experimental process by blank samples, standard reference materials and replicate samples, the analytical results of this method were accurate and reliable. The determination results of iodide in JSH-2 samples were 78.32μg/L. 　　(2) The determination values of iodide by ion chromatography (83.38μg/L) were consistent with those by HPLC-ICP-MS (78.32μg/L). However, the data of ion chromatography between different laboratories were obviously dispersed. The determination values of iodide by the starch spectrophotometry (92.95μg/L), catalytic reduction spectrophotometry (101.84μg/L) and ICP-MS (103.13μg/L) were higher than those by HPLC-ICP-MS. 　　(3) The reasons for the differences between the results of different methods were discussed, based on the principles and conditions of each method: 　 　① The determination results of ion chromatography may be affected by the selection of experimental conditions, such as sample pretreatment, chromatographic column and detector, and other interfering components. 　 　② It is not considered whether there is iodate ion in the sample itself in the starch spectrophotometry. Therefore, when there are iodate ions in the water sample, the determination result is actually the total content of inorganic iodine. 　　③ The standard working curve of the catalytic reduction spectrophotometry is bent downward as a whole and does not show a good linear relationship. Therefore, when the response value of iodide is high, the concentration value will be high. 　　④ ICP-MS is only used to determine the total content of elements, and cannot be used for elemental speciation analysis. There are iodate ions in the samples of this experiment, so the determination results of ICP-MS should be the total content of iodine, rather than the content of iodide. CONCLUSIONS: When iodate ions are present in water samples, starch spectrophotometry and ICP-MS may lead to a high result of iodide determination. Among them, starch spectrophotometry is usually suitable for samples with an iodide concentration of 25-500μg/L, and ICP-MS can be combined with other separation techniques to improve method selectivity. When iodate ions are present in water samples, catalytic reduction spectrophotometry and ion chromatography can be used to analyze the concentration of iodide, but the influence of sample concentration level, matrix interference components, experimental conditions and other factors should be considered. HPLC-ICP-MS can be applied to the quantitative analysis of iodine species in water samples, which can avoid the influence of iodate ions on the accuracy of iodide determination results. [ABSTRACT FROM AUTHOR]

Tenvermectin (TVM) is a novel 16‐membered macrolide compound isolated and purified from the fermentation broth of genetically engineered Streptomyces avermitilis strain MHJ1011. TVM and ivermectin were administered at the dose of 0.3 mg/kg body weight through a single subcutaneous injection route followed by plasma collectiom and analysis at different time intervals. Plasma concentrations of TVM and IVM were determined by high‐performance liquid chromatography with fluorescence detector. Pharmacokinetic analysis was completed using the non‐compartmental method with WinNonlin™ 6.4 software. TVM is rapidly absorbed after administration with peak plasma concentrations (Cmax, 9.78 ± 2.34 ng/ml) obtained within 6–22 h. AUC0‐last was 586.86 h·ng/ml ± 121.24 h·ng/ml. The mean elimination half‐life of TVM (T1/2λz) was 97.99 h ± 46.41 h. The T1/2λz of IVM was 146.59 h ± 22.26 h in the study. The present study showed that subcutaneous administration of TVM at 0.3 mg/kg body weight (BW) in swine is absorbed more rapidly than IVM in swine. Compared to the pharmacokinetic characteristics of IVM, there was little difference in the half‐life of TVM among different individuals. The data will contribute to refining the formulation and dosage regime for TVM administration. [ABSTRACT FROM AUTHOR]

Copyright of Plant & Soil Science is the property of National University of Life & Environmental Sciences of Ukraine 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.)

This study evaluates the formation of 13 polycyclic aromatic hydrocarbons (PAHs) in chicken thighs and breasts, cooked by different methods. These methods are: madhbi, charcoal mandi, electric oven mandi, gas flame oven mandi and shawaya. Chicken samples were collected from a restaurant in Riyadh, Saudi Arabia. Analysis of the samples was carried out using high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). The data obtained showed that madhbi chicken had higher PAHs levels than other cooking styles, with the mean concentration in chicken breast of 87.72 µg/kg and thigh of 75.56 µg/kg. Phenanthrene was the compound detected at the highest concentration in different cooking methods. There was no significant difference in concentration of PAHs between the parts of chicken cooked with the same method. However, the method of cooking had a significant impact on the formation of PHAs. Therefore, the formation of PAHs in chicken meat could be reduced by choosing appropriate cooking methods. Moreover, the margin of exposure was used to assess the health risk in adults due to madhbi chicken ingestion. The results showed that there is no serious health concern [ABSTRACT FROM AUTHOR]

The aim of this study from 2020 was to identify the role of rivers, including those with low water flow and a constant inflow of bisphenol A (BPA), 4-tert-octylphenol (4-t-OP) and 4-nonylphenol (4-NP) to the marine environment. Water samples were collected from the small rivers flowing into the Gulf of Gdańsk and from the Vistula River. Final assays were performed using high-performance liquid chromatography with a fluorescence detector (HPLC-FL). The highest concentrations of phenol derivatives were found in summer, most likely due to higher consumption of products containing phenol derivatives. Another factor may be the type of development in the catchment area. The measurements did not exceed the PNEC, though this does not mean that the amounts of phenol derivatives introduced into the Gulf of Gdańsk by rivers can be ignored. Mean loads of xenobiotics introduced to the sea via rivers have been calculated as over 320 kg y−1 of BPA and about 55 kg y−1 of 4-t-OP and 4-NP each. [ABSTRACT FROM AUTHOR]

New data on the fatty acid compositions of the muscle tissues of the two most widespread families of the mesopelagic zone—the Myctophidae (Notoscopelus kroyeri and Symbolophorus veranyi) and Stomiidae (Chauliodus sloani, Stomias boa, Borostomias antarcticus, and Malacosteus niger) families—were obtained from the Irminger Sea (North East Atlantic). The fatty acids (FAs) in the total lipids (TLs), phospholipids (PLs), triacylglycerols (TAGs), and cholesterol esters and waxes were analyzed using gas–liquid chromatography with a mass-selective detector and flame-ionized detector (GC-MS and GC-FID, respectively). Species-specific differences in the FA/alcohol profiles of the studied fishes were revealed. A directed deep-vise trend in the changes in the content and performance of certain FAs for the studied species was found. Along with this, a general character of dominance for monounsaturated fatty acids (MUFAs), which were discussed as food tracers, was revealed. MUFAs in the muscle tissues included dietary markers of zooplankton (copepods)—20:1(n-9) and 22:1(n-11), the content of which varied in association with the species—such that the biomarker Calanus glacialis predominated in muscles of B. antarcticus and C. hyperboreus prevailed in other studied species. Different strategies of compensatory adaptation to depth gradient in lipid metabolism among the studied species were discussed. [ABSTRACT FROM AUTHOR]

Pyrodinium bahamense var compressum is a harmful dinoflagellate that produces saxitoxin, which causes paralytic shellfish poisoning (PSP) that is deadly to humans. A non-axenic culture of P. bahamense was established using f/2 media from samples collected from Sepanggar Bay, Kota Kinabalu, Sabah. Toxin analyses of cultures harvested on days 60, 120, 180, and 360 were performed using high-performance liquid chromatography with a fluorescence detector and compared with samples collected at the same location during the bloom in 2021. The highest cell toxin content was found in the bloom sample (86.2 fmole/ cell), and no toxin was detected in the culture 60 days old. In addition, cell toxin content for the P. bahamense culture was low (9.4-16.5 fmole/cell). Based on the toxin profile, P. bahamense comprises 84-98% of gonyautoxin 4. In summary, the current findings add to the existing knowledge of the toxin profiling of P. bahamense, a toxic, harmful algal bloom species, thus, leading to better toxin management. [ABSTRACT FROM AUTHOR]

This study evaluated the bioavailability of polycyclic aromatic hydrocarbons (PAHs) in Santos Bay (SB) and the adjacent Santos Continental Shelf (SCS) in Brazil. Biliary metabolites were measured in several fish species to establish a baseline for future monitoring programs. Bile samples from different species of fish were collected monthly from July to December 2005 in SB, and in August 2005 and February 2006 on SCS. Metabolite concentrations were determined using high-performance liquid chromatography with fluorescence detectors. Naphthalene, phenanthrene, and benzo[a]pyrene metabolite concentrations ranged from 24 to 810 µg g-1 of bile, 1.8 to 68 µg g-1 of bile, and below the limit of quantitation to 1.3 µg g-1 of bile, respectively. Despite its high concentrations, the levels of naphthalene metabolites were in regions of low-contamination, while benzo[a]pyrene metabolite were in the same range as those reported in moderately contaminated areas, which may indicate pyrolytic contamination by PAHs. No significant differences in the metabolite concentrations were found between the SB and the SCS samples or during the periods of collection. Future studies with a single biomonitoring species should be conducted, considering age, sex, and feeding condition of the individuals. The metabolite data presented in this study is an important baseline information for this urbanized region, which hosts several sources of contaminants. [ABSTRACT FROM AUTHOR]

The objective of this work was to develop a method by ion chromatography with conductivity detector for the simultaneous determination of thiocyanate in mining wastewater and anions such as bromide, chloride, fluoride, phosphate, nitrite, nitrate and sulfate. Potassium hydroxide (KOH) was used as an eluent in a range of concentrations between 20,0 y 27,0 mM, flows between 0,4 y 1,2 mL min-1 and suppressor current between 50,0 y 70,0 mA. It was determined that the best separation of the species was achieved with a KOH concentration of 21,9 mM in isocratic mode and a flow of 1,0 mL min-1 in an AS20 analytical column. In addition, a series of analytical parameters such as sensitivity, linearity, precision, accuracy and limits of detection and quantification were determined that allow the validation of the analytical method. Relative standard deviation (RSD) values of less than 20 % were obtained in terms of the accuracy of the analytical method, with recoveries greater than 96 %. The method developed is therefore suitable for the determination of thiocyanate and anions in wastewater of mining origin. [ABSTRACT FROM AUTHOR]

Patulin (PAT) is a toxic secondary metabolite produced by certain species of Penicillium sp. and Aspergillus sp. on apples and pears. In this study, we investigated the effects of ascorbic acid and the combination of ascorbic acid and ferrous iron on degradation of PAT in 100% pure pear juice and apple juice using high-performance liquid chromatography UV detector (HPLC-UVD). The addition of 2 different levels of ascorbic acid (143 or 286 μg/mL) into pear juice or apple juice containing 0.08 or 0.4 μg/mL of PAT showed 87.7–100% and 67.3–68.7% of PAT degradation rates, respectively, after 24 h incubation at 25 °C. Moreover, the addition of both ascorbic acid (143 or 286 μg/mL) and ferrous iron (0.033 or 0.11 μmol/mL) into pear juice or apple juice containing the same level of PAT exhibited higher PAT degradation rates (100 and 75–94%, respectively) than the addition of only ascorbic acid after 24 h incubation at 25 °C. Our data demonstrated that ascorbic acid plus ferrous iron as well as ascorbic acid were highly effective on degradation of PAT in pear juice and apple juice and that addition of both ascorbic acid and ferrous iron produced higher PAT degradation rates than addition of only ascorbic acid. [ABSTRACT FROM AUTHOR]

This novel method, called layer by layer, is composed of alternate layers of graphene oxide and bismuth telluride nanoparticles, and to enhance the adsorption capacity the surface of nanoparticles was modified by 4-aminoantipyrine. A high-performance liquid chromatography with fluorescence detector technique was validated and used for analysis of nonylphenol extracted from environment water samples. Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray, thermogravimetric analysis, and X-ray diffraction spectroscopy were applied to characterize the nanoadsorbent. Under the optimum conditions (pH = 5, contact time = 15 min, temperature = 30°C, and initial nonylphenol concentration = 20 mg L–1), the developed technique shown the excellent reusability. Within the 5th cycle, the adsorption potential of recycled nanoadsorbent was restored by nearly 90% and this percentage decreased to 60% in the 8th cycle. The adsorption data fitted well with the Langmuir isotherm model (R2 = 0.9927) and pseudo-second-order kinetic model (R² = 1). The obtained nanoadsorbent possess the highest sorption capacity (43.47 mg g–1). Recoveries, at 1 µg mL–1 concentration level, ranged from 89% to 98% with relative standard deviations lower than 5% (n = 3). The results of nonylphenol removal from the environment samples shown the great applicability of nanoadsorbent for the removal of nonylphenol. [ABSTRACT FROM AUTHOR]

Advancements in column technology resulted in smaller particles and more efficient phases. In parallel, the use of columns with reduced dimensions is becoming more common. This means the effective column volume is also decreased, thereby making the systems more susceptible to effects of band broadening due to extra-column volume. Despite these trends and the fact that a growing number of miniaturized liquid chromatography systems are being offered commercially, manufacturers often stick to the modular concept with dedicated units for pumps, column oven, and detectors. This modular design results in long connection capillaries, which leads to extra-column band broadening and consequently prevents the exploitation of the intrinsic efficiency of state-of-the-art columns. In particular, band broadening post column has a considerable negative effect on efficiency. In this study, mass flow and concentration-dependent detectors were examined for their influence on band broadening using a micro-LC system. A mass spectrometric detector, an evaporative light scattering detector, two UV detectors, and a previously undescribed fluorescence detector were compared. The influence on efficiency is compared using plate height vs linear velocity data and peak variance. It is shown that an increase in the inner diameter after the post-column transfer capillary leads to significant loss in plate height. Comparing the UV detectors, it could be shown that the dispersion was reduced by 38% by the reduction of the post-column volume. The largest variance was found for the evaporative light scattering detector, which was 368% higher compared to the variance of the detector with the least effect on band broadening. [ABSTRACT FROM AUTHOR]

Histamine is a security issue in food safety as an indicator of the freshness of consumed fish product; that is why we aimed in this study to determine the histamine content in 7 fish species (Scomber japonicus; Sarda sarda; Sardinella aurita; S. maderensis; Ethmalosa fimbriata; Pomatomus saltatrix and Trachurus trachurus). Hundred and eight frozen and fresh pelagic of scombroid and non-scombroid species were collected from the Nouakchott fish market (Mauritanian Atlantic coast) in different period of 2020 and 2021. Histamine was quantified by the technique of high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). Histamine was detected in all analyzed fresh and frozen species and varied from 4.21 to 201.60 ppm. All evaluated fresh fish species (S. aurita; S. maderensis; E. fimbriata; P. saltatrix and T. trachurus) were conform to the FAO/WHO and the European commission regulations. Regarding investigated frozen fish species (S. aurita; S. japonicus and S. sarda); the scombroid species (S. japonicus and S. sarda) were all under the set limits; however, even its more likely for scombroid fish to develop histamine, our results showed that histamine exceed the limit in one sample of non-scombroid fish (S. aurita). No significant variation in histamine levels between scombroid and non-scombroid fish species was obtained; thereby, the study showed that fish product commercialized at the Nouakchott fish market have a good quality and safe for human consumption. [ABSTRACT FROM AUTHOR]

A new, rapid, efficient, low cost, robust, accurate and reproducible analytical method for the determination of Paraquat has been developed using reverse phase high performance liquid chromatography with UV-Visible detector (HPLC-UV). Paraquat is a frequently used herbicide. This method is useful for the detection and quantification of paraquat in raw materials and commercial samples with excellent recoveries upto almost 100%. pH of the mobile phase (acetonitrile:methanol:water 1:1:2) was optimized as 2.5 with ortho-phosphoric acid. This analytical method was validated with excellent linearity R² = 0.999. LOD and LOQ were calculated to be 0.74 mg/L and 2.45 mg/L, respectively. The method showed a high precision (RSD%) value of 0.32, while the accuracy measured in terms of percentage recovery was almost 100% under optimized conditions. The robustness of the method was studied by changing the flow rate and the mobile phase concentration ratios, and the results obtained were within the permissible accepted values. [ABSTRACT FROM AUTHOR]

Wagashie is an unripened traditional cheese consumed in West Africa including Ghana. Being a milk product, it is unfortunately susceptible to aflatoxin M1 (AFM1) contamination, which is indeed a grave health challenge globally. This study evaluated AFM1 levels and health risk characterization associated with wagashie (n = 182) sampled from different locations in Ghana. AFM1 was measured with high-performance liquid chromatography with a fluorescence detector (HPLC-FLD). Risk assessments were also conducted using models prescribed by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Out of the 182 samples analyzed for AFM1, 93/182 (51.1%) tested positive between the range 0.00 ± 0.00–3.60 ± 0.99 µg/kg. Risk assessments of AFM1 using deterministic models produced outcomes that ranged between 0.11 and 3.60 ng/kg bw/day, 0.09–1.54, 0–0.0323 ng aflatoxins/kg bw/day, and 3.5 x 10−3 −0.06 cases/100,000 person/yr for estimated daily intake (EDI), margin of exposure (MOE), average potency, and cancer risks, respectively, for the age categories investigated. It was established that the consumption of wagashie posed adverse health effects on all age categories in the selected regions of the study because all calculated MOE values were less than 100,000. Therefore, contamination of wagashie with AFM1 should be a serious public health concern and as such considered a high precedence for Ghana's risk management actions. [ABSTRACT FROM AUTHOR]

Mycotoxins are secondary metabolites produced by pathogenic fungi that colonize fruits and vegetables either during harvesting or during storage. Mycotoxin contamination in fruits and vegetables has been a major problem worldwide, which poses a serious threat to human and animal health through the food chain. This review systematically describes the major mycotoxigenic fungi and the produced mycotoxins in fruits and vegetables, analyzes recent mycotoxin detection technologies including chromatography coupled with detector (i.e., mass, ultraviolet, fluorescence, etc.) technology, electrochemical biosensors technology and immunological techniques, as well as summarizes the degradation and detoxification technologies of mycotoxins in fruits and vegetables, including physical, chemical and biological methods. The future prospect is also proposed to provide an overview and suggestions for future mycotoxin research directions. [ABSTRACT FROM AUTHOR]

In this study, the plasma pharmacokinetics and tissue disposition of sulfadiazine (SDZ) and its main metabolite, N4-acetyl sulfadiazine (ACT-SDZ), were compared between 18 and 24 °C following a single oral administration of SDZ at 50 mg/kg in grass carp (Ctenopharyngodon idella). The plasma and tissues were sampled from 0.167 h up to 96 h and analyzed by ultra-performance liquid chromatography with an ultraviolet detector. The pharmacokinetic parameters were estimated using a one-compartmental approach. Results showed that pharmacokinetics of SDZ and ACT-SDZ in plasma and tissues were notably influenced by the increase of temperature. The increased temperature shortened the absorption half-life (K01_HL) of SDZ and ACT-SDZ in gill, kidney, and plasma, but increased in liver and muscle + skin. The elimination half-life (K10_HF) and the area under concentration-time curve (AUC0–∞) of SDZ and ACT-SDZ all presented a declined trend. The apparent volume of distribution (V_F) of SDZ in plasma was increased from 0.93 to 1.64 L/kg, and the apparent systemic total body clearance (Cl_F) was also increased from 0.01 to 0.05 L/h/kg. Overall, the rise of temperature decreased K10_HF, AUC0–∞ of SDZ, and ACT-SDZ in plasma and tissues, but increased V_F and Cl_F in the plasma for SDZ. [ABSTRACT FROM AUTHOR]

Warfarin (WF) is an anticoagulant commonly used for thromboembolism-related diseases.This study aims to assess the pharmacokinetic profile of WF. The stereospecific interaction of S-and R-WF requires quantification of the enantiomer to determine the pharmacokinetic profile. The analysis method of the enantiomers in plasma is developed using an HPLC fluorescence detector with a Chiralcel OD-RH column (4.6 mm × 150 mm i.d., 5 m) and a Chiralcel OD-RH guard column (4.0 mm × 10 mm, 5 m). The separation is conducted using isocratic with acetonitrile mobile phase: Phosphate buffer, pH 2.00 (40:60 v/v), column temperature 40°C, flow rate 1 mL/min, injection volume 50 L. WF is measured at an excitation wavelength of 310 nm and emission of 350 nm. This method results in limit of detection (LOD) values of 18.6 ng/mL and limit of quantitation (LOQ) of 62.01 ng/mL for R-WF and LOD values of 18.61 ng/mL and LOQ of 62.04 ng/mL for S-WF. The results showed a linearity in concentration between 100 and 2500 ng/mL with r2 = 0.9969 and r2 = 0.9991 for R-and S-WF. The validation requirements of selectivity, accuracy, and precision for within and between run with a value of <15% for % relative standard deviation and % diff were achieved. This method can be used in the sample measurement of WF pharmacokinetic studies. [ABSTRACT FROM AUTHOR]

Context: Astaxanthin (Ast), a compound used widely as a dietary supplement, has high antioxidant properties but poor oral bioavailability. To benefit from its nutritional values in cognitive function, Ast was formulated into a nanoemulsion which may improve its penetration through the blood–brain barrier (BBB). Aim: The present study aims to quantitate the Ast nanoemulsion in different regions of the brain tissue using the high‑performance liquid chromatography method. Materials and Methods: Sprague–Dawley rats were fed with Ast nanoemulsion formulation daily (40, 80, and 160 mg/kg body weight, bw) for 28 days before brain tissues were harvested, extracted, and quantified. A simple, sensitive, and reliable method using high‑performance liquid chromatography with an ultraviolent detector was developed and validated to quantify Ast in the brain. Statistical Analysis: Data were analyzed using the ToolPak Data Analysis in Excel for t‑test and analysis of variance single factor with Tukey post hoc analysis. Results: The calibration curve demonstrated a linear regression with an r2 of 0.9998 and absolute recovery ranging from 97.8% to 109.6%. The hippocampus of the 160 mg/kg bw treatment group showed a significantly higher concentration of Ast (77.9 ± 17.3 µg/g) compared to the cortex (22.3 ± 4.2 µg/g) and cerebellum (33.1 ± 5.4 µg/g). Ast was detected in the cerebellum of the 80 mg/kg bw (29.4 ± 7.8 µg/g) treatment group with the amount not being significantly different to the 160 mg/kg bw (33.1 ± 5.4 µg/g) treatment group. Conclusions: It was evident that the Ast nanoemulsion formulated was able to cross the BBB and may provide protective benefits. [ABSTRACT FROM AUTHOR]

A simple, rapid, low-cost, and sensitive high-performance liquid chromatographic method was developed to determine tildipirosin in horse plasma. Plasma samples were extracted with diethyl ether, and after evaporation, tildipirosin was determined by reverse-phase chromatography with an ultraviolet detector set at a wavelength of 289 nm. Tildipirosin was separated on a Zorbax Eclipse XDB-C18 column, 150 x 3.0 mm, 5 µm with gradient chromatographic elution. The retention times were 3.0 min and 6.4 min for tildipirosin and tylosin tartrate, respectively. The total run time was 9 minutes in this method. Calibration curves ranged from 0.1 to 3 µg/mL. The lower limit of detection for plasma was 0.035 µg/mL, and the lower limit of quantitation was 0.1 µg/mL. Both accuracy and precision were always < 12% except for LLOQ < 20%. Mean recovery was 99.5 %. This procedure can be applied to determine tildipirosin concentrations in plasma and be useful to perform pharmacokinetic studies. [ABSTRACT FROM AUTHOR]

Biomass from agricultural processes is an important resource for fast pyrolysis and its transformation into bio-oil and high added value products. Several Standards of American Society for Testing and Materials (ASTM) were used in order to the physical-chemical characterization of the biomass used and the bio-oil obtained. Representative samples of biooil 0,82; pyroligneous acid 0,18 t, non-condensable gases 0,25 t and carbon 0,42 t were obtained by the fast pyrolysis from a mixture of Elephant Capín (Pennisetum purpureum) with sugar cane (Saccharum officinarum) straw. Nighty three organic compounds belonging to carboxylic acids, phenols, derivatives of furan, ethers of lignin, a homologous series of nalkanes from the bio-oil, and some aromatic nitrogenous compounds of high molar mass by gas chromatography with mass detector were identified. The caloric power of bio-oil is 20,20 MJ kg-1, facilitating its possible use as a biofuel. [ABSTRACT FROM AUTHOR]

Mycotoxin contamination of foodstuffs is a serious food safety concern globally as the prolonged ingestion of these toxins has the tendency to worsen the risk of hepatocellular carcinoma. This study aimed at estimating ochratoxin A (OTA) and aflatoxin (AF) levels above international (European Food Safety Authority, EFSA) and local (Ghana Standards Authority, GSA) standards as well as the health risks associated with the consumption of maize (n = 180) sampled from six (6) regions representing the agro-ecological zones of Ghana. OTA and AF were measured with High-Performance Liquid Chromatography with a Fluorescence detector. Out of the 180 samples analyzed for total aflatoxins (AFtotal), 131/180 tested positive and 127 (70.50%) exceeded the limits of EFSA and ranged 4.27–441.02 µg/kg. While for GSA, 116 (64.44%) of samples exceeded this limit and ranged between 10.18 and 441.02 µg/kg. For OTA, 103/180 tested positive and 94 (52.22%) of samples between the range 4.00–97.51 µg/kg exceeded the tolerable limit of EFSA, whereas 89 (49.44%) and were in the range of 3.30–97.51 µg/kg exceeded the limits of GSA. Risk assessment values for total aflatoxins (AFtotal) ranged between 50 and 1150 ng/kg bw/day, 0.4–6.67, 0–0.0323 aflatoxins ng/kg bw/day and 1.62–37.15 cases/100,000 person/year for Estimated Daily Intake (EDI), Margin of Exposure (MOE), Average Potency, and Cancer Risks respectively. Likewise, ochratoxin (OTA) values were in the ranges of 8.6 × 10–3–450 ng/kg bw/day, 0.05–2059.97, 0–0.0323 ochratoxins ng/kg bw/day and 2.78 × 10–4–14.54 cases/100,000 person/year. Consumption of maize posed adverse health effects in all age categories of the locations studied since the calculated MOE values were less than 10,000. [ABSTRACT FROM AUTHOR]

This paper reviewed the development of chromatography-mass spectrometry about promoting the analysis of multi-pesticide residues from the selectivity of low resolution mass spectrometry. The progress of mass spectrometry technology had changed the analytical method of pesticide residues. On the basis of clarifying the molecular structure of sample disruptors, the corresponding sample pre-treatment method was established. The selective detector of chromatography was replaced by mass spectrometry detector which collected molecular structure information. Selective ion detection technology and tandem mass spectrometry technology improved the ability of eliminate interferents. Based on mass spectrometry, methods for simultaneous multi-residue analysis of multiple pesticides were established. [ABSTRACT FROM AUTHOR]

A simple and sensitive RP-HPLC method developed for estimation of Polmacoxib in bulk by using a high performance liquid chromatography with PDA detector using Phenomenex luna C18 column (250mmx4.6mm), 5 μm; mobile phase comprises of Water : ACN as (1:1) at the flow rate 1.0 ml/min and the wavelength of detection 238 nm and eluted at 8.12 minutes. The proposed method is validated for specificity, Linearity, Precision, accuracy, ruggedness, and Robustness. All the parameters were found within the acceptable limits. RP-HPLC method was a simple, reliable economic and acceptable and it confirmed that method is suitable for the intended use for routine quality control and assay of drugs. This method is successfully applied for the determination of commercial dosage form capsule preparation. This method is validated as per ICH (International conference on harmonization) Guidelines. [ABSTRACT FROM AUTHOR]

A method for simultaneous determination of trace of four organophosphorus pesticides residues in animal liver samples has been developed and validated. This method is based on the preliminary sample preparation using extraction of target compound with a mixture of toluene-cyclohexane by means of up-to-date accelerated solvent extraction (ASE), liquid-liquid partitioning with acetonitrile and hexane, additional clean up step using QuEChERS method. Further the obtained analytes are determined by gas chromatography with ion-trap detector. The validation of the method is performed in accordance with the recommendations in Document SANTE/11945/2015 and it meets the acceptability criteria for precision, mean recovery and limits of quantification. The samples were investigated by analysing blank liver samples and samples spiked with the target analytes chlorpyrifos-methyl, parathion and pirimiphos-methyl at levels of 25, 50, and 75 ng/g and with diazinon at levels of 15, 30, and 45 ng/g. The recovery for all compounds were in the range from 73 to 104% which perfectly fit with requirements of documents and European legislations. The repeatability and within-laboratory reproducibility also reveal acceptable in documents coefficient of variation and uncertainty less than 20 and 18%, respectively. The limits of quantification were less than 3 ng/g for all compounds and allowed determination of residues below the maximum residue levels (MRLs) set in Regulation (EC) Nº 396/2005. [ABSTRACT FROM AUTHOR]

A gas detection system has been developed, characterized, and deployed for pressurized gas-phase sample analyses and near-real-time online measurements. It consists of a cryogenic pre-concentrator (CryoTrap), a gas chromatograph (GC), and a new high-resolution atomic emission detector (AED III HR). Here the CryoTrap–GC–AED instrumental setup is presented, and the performance for iodine (1635 ± 135 counts I atom -1 pptv -1), sulfur (409 ± 57 counts S atom -1 pptv -1), carbon (636 ± 69 counts C atom -1 pptv -1), bromine (9.1 ± 1.8 counts Br atom -1 pptv -1), and nitrogen (28 ± 2 counts N atom -1 pptv -1) emission lines is reported and discussed. The limits of detection (LODs) are in the low parts per trillion by volume range (0.5–9.7 pptv), and the signal is linear to at least 4 orders of magnitude, which makes it a suitable method for diverse volatile organic compound (VOC) measurements in the atmosphere, even in remote unpolluted regions. The new system was utilized in a field study in a boreal forest at Hyytiälä, Finland, in late summer 2016, which made monoterpene measurements possible among other VOCs. Furthermore, pressurized global whole-air samples, collected on board the Lufthansa Airbus A340-600 IAGOS–CARIBIC aircraft in the upper troposphere and lower stratosphere region, were measured with the new setup, providing data for many VOCs, including the long-lived organosulfur compound carbonyl sulfide. [ABSTRACT FROM AUTHOR]

Worldwide, 25% of the population suffers from metabolic syndrome (MetS). The treatment of patients with MetS regularly includes drugs prescribed simultaneously to treat several disorders that manifest at the same time, such as hypercholesterolemia, arterial hypertension, and diabetes. To the authors' best knowledge, there is no previous published analytical method for the simultaneous quantification of drugs used in the treatment of these diseases. In the present study, a rapid highperformance liquid chromatography with a diode-array detector HPLC-DAD methodology was developed for simultaneous quantification of carvedilol (CVD), telmisartan (TEL), bezafibrate (BZT), gliclazide (GZD), and glimepiride (GMP) in bulk and pharmaceutical form. The chromatographic separation of the five pharmaceuticals was achieved on a Hypersil GOLD C18 Selectivity (5 µm, 150 Ã--4.60 mm²) using a mobile phase of acetonitrile (50%) and 0.02 M KH2PO4, pH 3 (50%) at a flow rate of 1 mL/min and at 25 °C. The total separation time was 9 min. The analytical method was validated following the International Conference on Harmonization guidelines. A reproducible method was obtained with acceptable limits of detection (LOD) and quantification (LOQ) for CVD (0.012 and 0.035 µg mL-1), TEL (0.103 and 0.313 µg mL-1), BZT (0.025 and 0.076 µg mL-1), GZD (0.039 and 0.117 µg mL-1), and GMP (0.064 and 0.127 µg mL-1). The validated method allowed the determination of these drugs in commercial pharmaceutical products both individually and simultaneously. The present method was found to be suitable for simultaneous quantification of the five drugs that are most commonly used in the simultaneous treatment of the metabolic syndrome. [ABSTRACT FROM AUTHOR]

A porous aromatic framework (PAF) is shown to be a viable sorbent for the adsorption of phenols. To overcome the difficulty of quick adsorption and enrichment by phenols from the matrix, a sorbent material consisting of porous aromatic framework magnetic nanoparticles (PAF MNPs) with a core–shell structure was fabricated by an in situ growth method. The PAF MNP sorbent was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy and other techniques. The factors affecting enrichment performance including the amount of PAF-6 MNPs, sample pH, extraction time and elution conditions were optimized. Under the optimal conditions, a method utilizing high-performance liquid chromatography with an ultraviolet detector (HPLC-UV) was developed to quantify phenols in urine. The method showed good linearity (r ≥ 0.998), good precision (RSD ≤ 9.9%, n = 6) and a low limit of detection (1.0–2.0 ng/mL, S/N = 3), with recoveries performed in urine matrix ranging from 76.7% to 113.2%. The method is simple, time-saving and sensitive. Moreover, compared with traditional mass spectrometry detection methods, this method has advantages in terms of low cost and repeatability. [ABSTRACT FROM AUTHOR]

Free available chlorine (FAC) is the most widely used chemical for disinfection and in secondary disinfection; a minimum chlorine residual must be present in the distribution system. FAC can also be formed as an impurity in ClO2 production as well as a secondary oxidant in the ClO2 application, which has to be monitored. In this study, a new method is developed based on the reaction of FAC with glycine in which the amine group selectively scavenges FAC and the N-chloroglycine formed can be measured by ion chromatography with conductivity detector (IC-CD). Utilizing IC for N-chloroglycine measurement allows this method to be incorporated into routine monitoring of drinking water anions. For improving the sensitivity, IC was coupled with post-column reaction and UV detection (IC-PCR-UV), which was based on iodide oxidation by N-chloroglycine resulting in triiodide. The method performance was quantified by comparison of the results with the N,N-diethyl-p-phenylenediamine (DPD) method due to the unavailability of an N-chloroglycine standard. The N-chloroglycine method showed limits of quantification (LOQ) of 24 μg L−1 Cl2 and 13 μg L−1 Cl2 for IC-CD and IC-PCR-UV, respectively. These values were lower than those of DPD achieved in this research and in ultrapure water. Measurement of FAC in the drinking water matrix showed comparable robustness and sensitivity with statistically equivalent concentration that translated to recoveries of 102% for IC-CD and 105% for IC-PCR-UV. Repeatability and reproducibility performance were enhanced in the order of DPD, IC-CD, and IC-PCR-UV. Measurement of intrinsic FAC in the ClO2 application revealed that the N-chloroglycine method performed considerably better in such a system where different oxidant species (ClO2, FAC, chlorite, etc.) were present. [ABSTRACT FROM AUTHOR]