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A method for the simultaneous determination of benzimidazoles and their metabolites in dairy products was established using ultra high performance liquid chromatography-tandem mass spectrometry (MS). After extracting the samples with acetonitrile containing 0.2% formic acid, the extracts were centrifuged and purified by solid phase extraction column, and then separated by UPLC HSS T3 chromatographic column, determined in multi reaction monitoring (MRM) method with a positive ESI mode. The results showed that the linear correlation coefficient (r) within the range of 1.0~50 μg/L was greater than 0.995 (except for triclabendazole, which was 0.9578). The method had a limit of detection (LOD) (S/N=3) of 0.002 mg/kg (except for albendazole-2-aminosulfone, thiabendazole, and thiabendazole-5-hydroxy, which were 0.003 mg/kg). The limit of quantitation (LOQ) (S/N=10) was 0.005 mg/kg (except for albendazole-2-aminosulfone, thiabendazole, and thiabendazole-5-hydroxy, which were 0.010 mg/kg). The recoveries at three spiked levels of 0.005, 0.01 and 0.05 mg/kg ranged from 62.5% to 117.6%, with relative standard deviations (RSD) between 1.92% and 12.17%. The method is simple to operate, highly sensitive, and suitable for the quantitative analysis of benzimidazoles and their metabolites in dairy products.

Rationale: The sources and chemical compositions of organic aerosol (OA) exert a significant influence on both regional and global atmospheric conditions, thereby having far‐reaching implications on environmental chemistry. However, existing mass spectrometry (MS) methods have limitations in characterizing the detailed composition of OA due to selective ionization as well as fractionation during cold‐water extraction and solid‐phase extraction (SPE). Methods: A comprehensive MS study was conducted using aerosol samples collected on dusty, clean, and polluted days. To supplement the data obtained from electrospray ionization (ESI), a strategy for analyzing OAs collected using the quartz fiber filter directly utilizing laser desorption ionization (LDI) was employed. Additionally, the ESI method was conducted to explore suitable approaches for determining various OA compositions from samples collected on dusty, clean, and polluted days. Results: In situ LDI has the advantages of significantly reducing the sample volume, simplifying sample preparation, and overcoming the problem of overestimating sulfur‐containing compounds usually encountered in ESI. It is suitable for the characterization of highly unsaturated and hydrophobic aerosols, such as brown carbon‐type compounds with low volatility and high stability, which is supplementary to ESI. Conclusions: Compared with other ionization methods, in situ LDI helps provide a complementary description of the molecular compositions of OAs, especially for analyzing OAs in polluted day samples. This method may contribute to a more comprehensive MS analysis of the elusive compositions and sources of OA in the atmosphere. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study investigated per‐ and polyfluoroalkyl substances (PFASs) in 53 fruit and vegetable samples collected from a local wholesale and retail market in Sydney and a local supermarket in Newcastle. As there is limited information about PFAS levels in vegetables on the market, this study aimed to fill this gap and assess potential risks for humans through consumption of these vegetables. METHODS: QuEChERS extraction – a solid‐phase extraction method, a portmanteau word formed from 'quick, easy, cheap, effective, rugged and safe' – followed by enhanced matrix removal–lipid cleaning and liquid chromatography–tandem mass spectrometry analysis were used to detect 30 PFASs in vegetables. RESULTS: PFOA was detected in 7 out of the 53 samples, with concentrations of 0.038–1.996 ng g−1 fresh weight; PFOS was detected in 2 samples only, with concentrations ranging from 0.132 to 0.911 ng g−1 fresh weight. PFHxS was not detected in any sample in this study. PFOA and PFOS concentrations measured in vegetables in this study constituted daily intake of 2.03 ng kg−1 body weight (BW) and 1.98 ng kg−1 BW, respectively, according to recommended daily vegetable intake and BW data from the Australian Bureau of Statistics. The most sensitive population group is girls of 4–8 years of age. These estimated exposure levels represent up to 1.3% of the tolerable daily intake for PFOA (160 ng kg−1 BW) and 9.9% for PFOS (20 ng kg−1 BW) according to Food Standards Australia New Zealand. Consumption of the vegetables from the study locations poses a marginal risk to human health. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study investigates the presence of new psychoactive substances (NPS) and their metabolites in two wastewater treatment plants (WWTPs) situated in South Wales, UK (WWTP-1 and WWTP-2). Analysis was conducted for 35 NPS and metabolites, along with the inclusion of benzoylecgonine (main cocaine metabolite) and cannabis, the most detected illicit substances. Benzoylecgonine was identified as the predominant substance in both WWTPs. Epidemiological calculations revealed the average population consumption of cocaine to be 3.88 mg/d/1000 inhabitants around WWTP-1 and 1.97 mg/d/1000 inhabitants for WWTP-2. The removal efficiency of benzoylecgonine across both WWTPs was observed at an average of 73%. Subsequent qualitative analyses on randomly selected wastewater samples detected medicinal compounds including buprenorphine, methadone, and codeine in both WWTPs. An additional experiment employing enzymatic hydrolysis revealed the presence of morphine, an increased presence of codeine, and 11-Nor-9-Carboxy-THC (THC-COOH) post-hydrolysis. These findings underscore the significant presence of illicit substances and medicinal compounds in wastewater systems with the absence of NPS within the South Wales area, highlighting the necessity for enhanced monitoring and treatment strategies to address public health and environmental concerns. [ABSTRACT FROM AUTHOR]

Introduction: The presence of pharmaceuticals and personal care products in environmental matrices is considered one of the major scientific concerns. Most of these substances are disposed of unchanged through wastewater treatment plants and sewage systems. Consequently, they are continuously introduced into the water systems and progressively contaminate surface, ground and drinking water. During the COVID-19 pandemic, a large number of emerging contaminants including parabens were released to the environment through various routes. In this study, the occurrence of parabens (methylparaben (MePB), ethylparaben (EtPB), propylparaben (PrPB), and butylparaben (BuPB) was investigated in wastewater samples from various wastewater treatment plants (WWTPs) and the receiving surface waters in KwaZulu Natal and Gauteng Provinces (South Africa). Methods: The samples were collected between October 2020 and December 2021, covering the 2nd, 3rd and 4th waves of the COVID-19 pandemic. A solid phase extraction protocol with high-performance liquid chromatography was used to extract and enrich parabens before analysis. Results and Discussion: Methylparaben (2.02-84.7 μg/L), EtPB (<0.24-24.8 μg/L), PrPB (<0.26-55.1 μg/L), and BuPB (<0.27-17.3 μg/L) were quantified in wastewater influent collected WWTPs of KwaZulu Natal Province. While <0.19-5.43 μg/L, <0.16-5.63 μg/L, <0.17-6.89 μg/L, and <0.19-5.32 μg/L for MePB, EtPB, PrPB, and BuPB, respectively, were quantified in effluent wastewater from the same province. The concentrations of MePB, EtPB, PrPB, and BuPB in influent wastewater from Gauteng Province were 2.58-123 μg/L, <0.24-33.6 μg/L, 3.77-73.4 μg/L and <0.27-85.8 μg/L, respectively. In effluent wastewater, concentrations ranging from 0.24-17.76 μg/L (MePB), <0.16-4.88 μg/L (EtPB), 0.69-12.5 μg/L (PrPB), and <0.19-4.726 μg/L (BuPB) were quantified. During the 4th wave, the concentrations of parabens in surface water were lower compared to the second and third waves of the pandemic. In general, the paraben residues in the surface of KwaZulu Natal Province (<0.08-16.4 μg/L) were higher than those in Gauteng Province (0.08-3.14 µg/L). Methylparaben and propylparaben were dominant in all investigated samples (wastewater and surface water), followed by ethylparaben. The ecotoxicological risk assessment was carried out for aquatic biota, which was estimated in terms of risk quotients (RQs). RQs for the target compounds in river water indicated that MePB and EtPB pose low risk, whereas PrPB and BuPB pose low to medium risk to aquatic organisms. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are continuously emitted into the atmosphere from natural and anthropogenic sources and rapidly spread from the atmosphere to different environments. A large group of VOCs has been included in the class of air pollutants; therefore, their determination and monitoring using reliable and sensitive analytical methods represents a key aspect of health risk assessment. In this work, an untargeted approach is proposed for the evaluation of the exposure to volatile organic compounds of workers in an engine manufacturing plant by GC–MS measurements, coupled with solid-phase microextraction (SPME). The analytical procedure was optimized in terms of SPME fiber, adsorption time, desorption time, and temperature gradient of the chromatographic run. For the microextraction of VOCs, the SPME fibers were exposed to the air in two different zones of the manufacturing factory, i.e., in the mixing painting chamber and the engine painting area. Moreover, the sampling was carried out with the painting system active and running (system on) and with the painting system switched off (system off). Overall, 212 compounds were identified, but only 17 were always present in both zones (mixing painting chamber and engine painting area), regardless of system conditions (on or off). Finally, a semi-quantitative evaluation was performed considering the peak area value of the potentially most toxic compounds by multivariate data analyses. [ABSTRACT FROM AUTHOR]

The composition of medium-volatile organic matter (OM) was studied in the steam–water mixture condensate (SWC) from deep production wells of the Pauzhetka geothermal field. Using solid-phase extraction and chromatography–mass spectrometry, 17 organic compounds, including 14 aliphatic and aromatic hydrocarbon (HC), were identified in the studied SWC. These components are strongly dominant in the Pauzhetka hydrothermal system and a number of other geothermal fields in Kamchatka, with their average contents amounting to higher than 60%. According to the specifics of the molecular weight distribution of the saturated HC, the high temperature of the steam–water mixture condensate (more than 108°C at the wellhead), and the absence of obviously biogenic components, these HC are thought to be produced by thermogenic processes: the transformation of organic remnants under the effect of high temperatures and pressures. The contents of the other compounds are much lower, and these components are mostly oxygen-containing compounds (ketones, aldehydes, and alcohols). Similarities between the spectra of organic compounds in the Pauzhetka and Uzon SWC may be at least partly explained by their extraction from volcanogenic–sedimentary layers containing buried organic matter. [ABSTRACT FROM AUTHOR]

Among the various compounds regarded as emerging contaminants (ECs), pharmaceuticals and personal care products (PPCPs) are of particular concern. Their continuous release into the environment has a negative global impact on human life. This review summarizes the sources, occurrence, persistence, consequences of exposure, and toxicity of PPCPs, and evaluates the various analytical methods used in the identification and quantification of PPCPs in a variety of solid and liquid environmental matrices. The current techniques of choice for the analysis of PPCPs are state-of-the-art liquid chromatography coupled to mass spectrometry (LC-MS) or tandem mass spectrometry (LC-MS2). However, the complexity of the environmental matrices and the trace levels of micropollutants necessitate the use of advanced sample treatments before these instrumental analyses. Solid-phase extraction (SPE) with different sorbents is now the predominant method used for the extraction of PPCPs from environmental samples. This review also addresses the ongoing analytical method challenges, including sample clean-up and matrix effects, focusing on the occurrence, sample preparation, and analytical methods presently available for the determination of environmental residues of PPCPs. Continuous development of innovative analytical methods is essential for overcoming existing limitations and ensuring the consistency and diversity of analytical methods used in investigations of environmental multi-class compounds. [ABSTRACT FROM AUTHOR]

Wastewater (WW)-based epidemiology is an approach for the objective surveillance of the consumption of (illicit) drugs in populations. The aims of this study were to monitor drugs of abuse, cognitive enhancers, and their metabolites as biomarkers in influent WW. Data obtained from different sampling points and mean daily loads were compared with previously published data. The prevalence of analytes was monitored in WW grab samples collected monthly over 22 months at two sampling points and 24 h composite WW samples collected over 2 weeks at a WW treatment plant in the same city. Quantification was performed using a previously validated and published method based on solid-phase extraction followed by liquid chromatography coupled with high-resolution tandem mass spectrometry. Grab samples allowed for frequent detection of ritalinic acid and sporadic detection of drugs of abuse. The daily mean loads calculated for 24 h WW composite samples were in accordance with data published in an international study. Furthermore, loads of amphetamine and methamphetamine increased compared with those observed in a previously published study from 2014. This study showed frequent quantification of ritalinic acid in the grab samples, while drugs of abuse were commonly quantified in the composite WW samples. Daily mean loads were in accordance with trends reported for Germany. [ABSTRACT FROM AUTHOR]

In this study, the levels of six PAEs [bis (2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP), diethyl phthalate (DEP), dimethyl phthalate (DMP) and di-n-octyl phthalate (DNOP)] were determined from four types of bottled water)non-carbonated, mineral, carbonated and carbonated flavoured) using MSPE method (magnetic solid phase extraction) and GC/MS technique (gas chromatography/mass spectrometry). The mean concentration of total PAEs was 6.11 ± 1.43 µg/L. The mean concentration of DEHP was 2.22 ± 0.76 µg/L and was lower than the United States Environmental Protection Agency (USEPA) standard level in drinking water (6 μg/L for DEHP). The highest mean level of total PAE was observed in carbonated water (7.43 ± 2.03 μg/L) and the lowest mean level of total PAE was observed in non-carbonated water (5.15 ± 0.41 μg/L). The Monte Carlo method was applied to calculate the Target Hazard Quotient (THQ), Chronic Daily Intake (CDI), and Incremental Life Cancer Risk (ILCR) indexes. In all samples, the rank order of the estimated THQ values based on the 95% percentile was DEHP (4.77E-4) > DBP (2.25E-5) > BBP (1.99E-5) > DEP (2.75E-6) and there would be unlikely non-carcinogenic risks for consumers (THQ<1). The incremental lifetime cancer risk assessment revealed that phthalate esters (DEHP) in evaluated bottled water samples did not pose a serious concern to humans. [ABSTRACT FROM AUTHOR]

Organophosphates are widely used in the livestock industry. In this study, we developed a method for detecting 27 organophosphate insecticides in animal-derived foods, including beef, pork, chicken, milk, and eggs, using liquid chromatography–tandem mass spectrometry. A modified QuEChERS method was optimized for sample pretreatment. A mixture of acetonitrile and acetone was used as the extraction solvent, and MgSO4 and NaCl were used as salts. Among the five different dispersive solid-phase extraction systems, MgSO4, primary secondary amines, and C18 were selected for purification because they had the highest recovery rates and least matrix effects. The matrix-dependent limit of quantitation was 0.0005–0.005 mg/kg, and the correlation coefficient of the matrix-matched calibration curve was >0.99, which was acceptable for quantifying residues below 0.01 mg/kg—the default maximum residue limit in a positive list system. The recovery efficiencies ranged from 71.9 to 110.5%, with standard deviations ranging from 0.2% to 12.5%, satisfying the SANTE guidelines. The established analytical method was used to monitor organophosphates in animal-derived foods obtained from a local market, and no pesticides were detected. With respect to industry standards, our proposed method is recommended for practical organophosphate detection in animal-derived foods. [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]

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Antimicrobial resistance (AMR) is one of the most alarming global public health challenges of the 21st century. Over 3 million antimicrobial-resistant infections occur in the United States annually, with nearly 50,000 cases being fatal. Innovations in drug discovery methods and platforms are crucial to identify novel antibiotics to combat AMR. We present the isolation and characterization of potentially novel antibiotic lead compounds produced by the cross-feeding of two rhizosphere bacteria, Acinetobacter sp. RIT 592 and Exiguobacterium sp. RIT 594. We used solid-phase extraction (SPE) followed by liquid chromatography (LC) to enrich antibiotic extracts and subsequently mass spectrometry (MS) analysis of collected fractions for compound structure identification and characterization. The MS data were processed through the Global Natural Product Social Molecular Networking (GNPS) database. The supernatant from RIT 592 induced RIT 594 to produce a cocktail of antimicrobial compounds active against Gram-positive and negative bacteria. The GNPS analysis indicated compounds with known antimicrobial activity in the bioactive samples, including oligopeptides and their derivatives. This work emphasizes the utility of microbial community-based platforms to discover novel clinically relevant secondary metabolites. Future work includes further structural characterization and antibiotic activity evaluation of the individual compounds against pathogenic multidrug-resistant (MDR) bacteria. [ABSTRACT FROM AUTHOR]

A new method for screening 300 pesticide residues in fruit‐, vegetable‐, and cereal‐based baby foods by an improved QuEChERS purification method based on amino‐functionalized multiwalled carbon nanotubes (NH2‐MWCNTs) combined with gas chromatography‐electrostatic field orbitrap high‐resolution mass spectrometry (Orbitrap GC‐MS) was developed. The samples were extracted with acetonitrile (dry sample soaked in water first for activation), purified by dispersed solid phase extraction (d‐SPE) tube modified by NH2‐MWCNTs, and detected by Orbitrap GC‐MS. Qualitative analysis was carried out by retention time and accurate mass measurements in full scan mode, and external standard method for quantitation was performed using matrix‐matched standard calibration, which could effectively eliminate matrix interference. Method validation was performed on commercially available fruit‐, vegetable‐, and cereal‐based baby foods. Good linearity was achieved for 300 pesticides in the concentration range of 5 to 500 μg/kg with correlation coefficients greater than 0.995 0. The limits of detection (LOD) were 0.3–3.0 μg/kg, and the limits of quantification (LOQ) were 1.0–10.0 μg/kg. The average recoveries on 10, 50, and 200 μg/kg spiked levels were in the range of 72.8%–123.4% in three types of samples, with relative standard deviations (RSDs) of 2.0%–13.3%. The proposed method, with simple pretreatment, highly sensitivity, high precision, and accuracy, is suitable for simultaneous analysis of 300 pesticide residues in baby foods. This method provides a reference for accurate screening of low pesticide residues in baby food. [ABSTRACT FROM AUTHOR]

Bisphenols are widely used as monomers and additives in plastic production. Thus, bisphenol A (BPA) and its most prominent substitutes have been detected in many environmental and human samples. This study proposes an online solid-phase extraction analytical methodology coupled to liquid chromatography with tandem mass spectrometry for the determination of six bisphenols (BPA and bisphenols F (BPF), S (BPS), AF (BPAF), B (BPB), and E (BPE)) in urine samples as an efficient and automated methodology. The method was developed and validated for all bisphenols with good recoveries (92–112%) and repeatability (RSD ≤ 10%) despite the variable matrix effects, except BPAF (which would require a dedicated internal standard), achieving method quantification limits in the 0.05–2.2 ng mL−1 range. The methodology was subsequently applied to 435 urine samples from a non-occupational exposure population (civil servants for the regional government) from Santiago de Compostela (Galicia, Spain). Only BPA, BPF, and BPS were positively detected; the last two presented higher detection frequencies than BPA. When the urinary concentrations are extrapolated to human intake and compared to the European Food Safety Agency (EFSA) tolerable daily intake (TDI) of 2 × 10−4 µg kg−1 day−1 (TDI), all BPA positively identified samples would surpass this threshold. Although no TDI exists currently for the other two identified bisphenols, it is evident that human exposure to bisphenols should be limited. Finally, the results stratification by gender revealed higher levels of exposure to BPF in the women group. [ABSTRACT FROM AUTHOR]

An alternative solid phase extraction (SPE) material, 1‐butyl‐3‐methylimidazolium chloride–silver nanoparticles/eggshell membrane ([BMIM]Cl‐AgNPs/ESM), is developed by synthesizing [BMIM]Cl‐AgNPs using a simple reduction method and immobilizing directly on ESM. The newly developed material is successfully applied for extraction and detection of sulfamethoxazole (SMX) in environmental aqueous samples via a high‐performance liquid chromatography‐diode array detector (HPLC‐DAD). Characterization is accomplished by Fourier transform infrared (FTIR) and field emission scanning electron microscopy/energy dispersive X‐ray (FESEM/EDX), confirming the presence of [BMIM]Cl‐AgNPs on ESM. The optimization of [BMIM]Cl‐AgNPs/ESM‐based SPE method is studied by the one variable at a time (OVAT) approach. Method validation shows good linearity (R2 = 0.9995) in the range of 10–500 µg L−1, with the detection and quantification limits determined to be 3.07 and 9.31 µg L−1 respectively. Additionally, a reusability study shows the developed material can extract SMX up for three cycles without significant reduction in its efficiency. Excellent recoveries (90.07–104.08%) in spiked tap and lake water demonstrate the potential of [BMIM]Cl‐AgNPs/ESM for trace‐level detection of pollutants. [ABSTRACT FROM AUTHOR]

An automated flow analysis-solid phase extraction (FA-SPE) system and methodology of ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) analysis were developed for the determination of selected antiviral drugs (acyclovir, amantadine, rimantadine, and oseltamivir) in water samples. The proposed FA-SPE approach enables the integration of various extraction stages and elimination of the sample evaporation step and offers individual customisation of SPE parameters, inter alia sample, and eluate flow rate and volume. Using the developed FA-SPE procedure, e.g. a 100-fold preconcentration of the target analytes in 1 h was achieved. A method for chromatographic analysis was also developed to determine the selected antiviral drugs in combination with the use of the FA-SPE system. The developed FA-SPE UHPLC-MS/MS method was validated including the determination of linearity of analytical graphs, limits of detection (5.5–99.9 pg mL−1) and quantification (18.3–329.8 pg mL−1), intra-day (1.8–8.3%) and inter-day (3.0–9.2%) precision, recovery (95.6–105.3%), and matrix effects (− 12.9 to 13.2%). The proposed method was successfully applied to analyse tap, drinking, and river water samples, revealing the presence of amantadine at a concentration of 40.1 pg mL−1 in one sample. The environmental impact of the developed FA-SPE sample preparation procedure was also assessed using the AGREEprep metric tool and compared with five other literature methods, achieving the most sustainable outcome. [ABSTRACT FROM AUTHOR]

In order to investigate the mechanism of plant growth promoting (PGP) effects of strain Bacillus velezensis WSW007, its PGP traits and production of volatile organic compounds (VOCs) were tested. The effects of VOCs produced by strain WSW007 on plant growth were observed by co-culturing this strain with tobacco seedlings in I-plates. Meanwhile, the effects of VOCs on tobacco gene expression were analysed by a transcriptome analysis and VOCs were identified by solid phase micro extraction coupled with gas chromatography-mass spectrometry (SPME-GC-MS) analysis. As results, strains WSW007 produced acetic acid and siderophore, and could solubilize phosphate; while it also significantly increased the fresh weight of tobacco seedlings via production of VOCs. In transcriptome analysis, plants co-cultured with strain WSW007 presented the highest up-regulated expression for the genes involved in plant growth and development processes, implying that the bacterial VOCs played a role as regulator of plant gene expression. Conclusively, the up-regulation in expression of growth- and development-related genes via VOCs production is an important PGP mechanism in strain B. velezensis WSW007. [ABSTRACT FROM AUTHOR]

An automated method has been developed for the synthesis of [N-methyl-11C]choline, a radiopharmaceutical (RP) for the diagnosis of cancer using positron emission tomography (PET). The synthesis was carried out on a home-made module, using combined technology of on-line 11C-methylation processes and solid-phase extraction methods. The radiochemical yield of [N-methyl-11C]choline was 80% (based on the activity of the methylating agent, [11C]CH3I, decay corrected), which ensures the production of several clinical doses of radiopharmaceutical in one batch. [N-Methyl-11C]choline was obtained with a radiochemical purity of more than 99% and an amount of 2-dimethylaminoethanol (the main chemical impurity) of 0.06 mg/mL, which meets the requirements of the Russian and European Pharmacopoeia. [ABSTRACT FROM AUTHOR]

UV spectrophotometric determination of salicylic acid in several multicomponent drugs using an ethylcellulose-based sorbent for solid-phase extraction (SPE) for sample preparation was shown to be selective. Selective binding of the analyte to sorbent active sites and stepwise elution successively with purified water and NaOH solution (0.1 M) during SPE eliminated interference of other active pharmaceutical ingredients of multicomponent drugs during identification and quantitation of salicylic acid by UV spectrophotometry. Use of the ethylcellulose sorbent made it possible to improve the metrological parameters and decrease systematic error of the quantitative procedure by an average of 47%. [ABSTRACT FROM AUTHOR]

Background and Aims: Caffeine is a xanthine alkaloid found naturally in plants. Caffeine has cardiotonic and stimulant effects in humans and animals. For this reason, caffeine is on the monitoring list for human sports and is listed as a feed contaminant in horse racing. The aim of this study was to develop a rapid, practical, and specific method for the determination of caffeine in horse urine. Methods: In the new method, the pH of the sample was adjusted by the addition of phosphate buffer, and after solid phase extraction, it was dissolved in methanol before being analysed by gas chromatography mass spectrometry without derivatization. The method was validated according to the European Commission’s 2002/657/EC criteria. Results: The effects of different cartridge brands, pH, and elution solution were determined. Intraday and interday CV% values are 2.8 and 5.2 for the International Residue Limit (IRL), respectively. Five levels (blank, 0.5xIRL, IRL, 1.5xIRL, and 2xIRL) were used in constructing the curve, and the R2 value was greater than 0.99. The analysis run was 11.8 min. The decision limit (CCα) was determined to be 56.7 ng/mL due to IRL. The detection limit of the method was calculated to be 3.3 ng/mL. The method was determined to be robust according to changes in extraction pH, phosphate buffer concentration, centrifugation time, hexane volume in the wash step, different grades of methanol, inlet temperature, and operator. Conclusion: The applicability of the method was demonstrated by analysing positive and negative horse urine samples. Validation parameters showed the method to be selective, specific, and easy to apply. [ABSTRACT FROM AUTHOR]

Anamorelin, a non-peptide ghrelin analog and growth hormone secretagogue, is a novel oral drug used to treat cancer cachexia. Patients with cancer cachexia frequently use several drugs and anamorelin is a substrate of cytochrome P450 (CYP) 3A4; therefore, drug-drug interactions with CYP3A4 inhibitors and inducers pose a clinical problem. In this study, we aimed to determine the concentration of anamorelin in human plasma using a simple high-performance liquid chromatography-ultraviolet (HPLC-UV)-based method. The analysis involved extracting a 200-µL plasma sample and protein precipitation using solid-phase extraction. Anamorelin was isocratically separated using a mobile phase consisting of 0.5% potassium dihydrogen phosphate (pH 4.5) and acetonitrile (61:39, v/v) on a Capcell Pack C18 MG II column (250 mm × 4.6 mm) at a flow rate of 1.0 mL/min and monitored at a detection wavelength of 220 nm. The calibration curve was linear within a plasma concentration range of 12.5-1,500 ng/mL, with a coefficient of determination of 0.9999. The intra- and inter-day coefficients of variation were 0.37-6.71% and 2.05-4.77%, respectively. The accuracy of the assay and recovery were 85.25-112.94% and > 86.58%, respectively. This proposed HPLC-UV method is simple and can be applied in clinical settings. [ABSTRACT FROM AUTHOR]

The increasing occurrence of saxitoxins in freshwaters is becoming a concern for water treatment facilities owing to its structural properties which make it resistant to oxidation at pH, 8. Hence, it is crucial to be able to monitor these toxins in surface and drinking water to protect public health. This review aims to outline the current state of knowledge related to the occurrence of saxitoxins in freshwaters and its removal strategies and provide a critical assessment of the detection methods to provide a basis for further development. Temperature and nutrient content are some of the factors that influence the production of saxitoxins in surface waters. A high dose of sodium hypochlorite with sufficient contact time or activated carbon has been shown to efficiently remove extracellular saxitoxins to meet the drinking water guidelines. While HILIC-MS has proven to be a powerful technology for more sensitive and reliable detection of saxitoxin and variants after solid phase extraction, ELISA is cost-effective and easy to use and is used by Ohio EPA for surveillance with a limit of detection of 0.015 μg/L. However, there is a need for the development of cost-effective and sensitive techniques that can quantify the variants of saxitoxin. [ABSTRACT FROM AUTHOR]

Objective To establish a method for the quantitative analysis of iodine and its compounds in workplace air by ion chromatography pulsed amperometric detector. Methods Air samples were collected using alkaline -activated carbon solid -phase extraction tubes and eluted with 10 mL of the 20 mmol/L sodium bicarbonate solution for 30 minutes. The eluate was separated using the Dionex ICS -5000 ion chromatography system with the Dionex IonPac AS11 -HC high - performance anion separation column and detected by the pulsed amperometric detector, with the retention time for qualitative analysis and the peak area for quantitative analysis. Results The method had a correlation coefficient of 0.999 7 for the standard curve, a detection limit of 0.519 μg/L (25 μL injection volume), and a minimum quantifiable mass concentration of 2.3 μg/m³ calculated using a sampling volume of 7.5 L. The method had good reproducibility, with relative standard deviations ranging from 2.72% to 4.10% and an internal recovery rate of 95.8% to 98.0% for simulated samples. The average elution efficiency of alkaline-activated carbon solid-phase extraction tubes was more than (94.1% ± 2.65% ). Iodine and its compounds could be stably stored for 5 days at 4 ℃ . Conclusions The quantitative analysis method of the ion chromatography pulsed amperometric detector was fast, convenient, efficient, and accurate. It is satisfied with the requirement for the determination of iodine and its compounds in workplaces [ABSTRACT FROM AUTHOR]

• Water samples extracted by different SPE methods showed distinct biotoxicities. • Biotoxicity outcomes of extracted water samples were proportional to the chemical extracting efficiencies of SPE methods. • HLB+Coconut ranked as the Pareto best for biotoxicity assessment among 5 SPE methods. • Biotoxicity outcomes and chemical extracting efficiencies synchronously decrease with increasing SVPC during SPE. Biotoxicity assessment results of environmental waters largely depend on the sample extraction protocols that enrich pollutants to meet the effect-trigger thresholds of bioassays. However, more chemical mixture does not necessarily translate to higher combined biotoxicity. Thus, there is a need to establish the link between chemical extracting efficiency and biotoxicity outcome to standardize extraction methods for biotoxicity assessment of environmental waters. This study compares the performance of five different extraction phases in solid phase extraction (SPE), namely HLB, HLB+Coconut, C18 cartridge, C18 disk and Strata-X, and evaluated their chemical extracting efficiencies and biotoxicity outcomes. We quantitatively assessed cytotoxicity, acute toxicity, genotoxicity, estrogenic activity, and neurotoxicity of the extracts using in vitro bioassays and characterized the chemical extracting efficiencies of the SPE methods through chemical recoveries of 23 model compounds with different polarities and total organic carbon. Using Pareto ranking, we identified HLB+Coconut as the optimal SPE method, which exhibited the highest level of water sample biotoxicity and recovered the most chemicals in water samples. We found that the biotoxicity outcomes of the extracted water samples significantly and positively correlated with the chemical extracting efficiencies of the SPE methods. Moreover, we observed synchronous changing patterns in biotoxicity outcome and chemical extracting efficiencies in response to increasing sample volumes per cartridge (SVPC) during SPE. Our findings underscore that higher chemical extracting efficiency of SPE corresponds to higher biotoxicity outcome of environmental water samples, providing a scientific basis for standardization of SPE methods for adequate assessment of biotoxicities of environmental waters. [Display omitted] [ABSTRACT FROM AUTHOR]

The high concentration of active substances in tomato extraction is correlated with its anti-tyrosinase and antioxidant effect activity. We established the optimum ultrasound extraction conditions for maximizing the yield of active substances. The four important factors (ethanol concentration, extraction time, extraction temperature, and solid-liquid ratio) that greatly affected ultrasonic extraction were selected to set up a single-factor test and investigate the effects of inhibitory activity on tyrosinase. According to the result of the single-factor test, the orthogonal experiment was conducted to select the optimum process parameter of extracting a total active substance from tomatoes by the alcohol extraction method. The factors affecting the extraction of active substances from tomatoes by an ultrasonic assistant method in order were as follows: ethanol concentration > solid-liquid ratio > extraction temperature > extraction time. The optimum process condition from the orthogonal experiment was as follows: ethanol concentration of 80%, solid-liquid ratio of 1:6, extraction temperature of 50°C, and extraction time of 50 min, under which the average anti-tyrosinase activity of active substances was 32.77% through the tyrosinase inhibition assay. [ABSTRACT FROM AUTHOR]

Parabens are frequently used preservatives in food and personal care products. These are also termed endocrine disruptors which have the potential to damage the endocrine system Therefore, an easy and facile extraction and detection of parabens are critically important. This work evaluates different magnetic sorbents such as Fe3O4@MIL‐101(Cr), Fe3O4@MIL‐101(Cr)@NH2, and Fe3O4@MIL‐101(Cr)@SO3H for magnetic solid phase extraction (MSPE) and further selected Fe3O4@MIL‐101(Cr)@NH2 to determine paraben content in chili powder and facial toner samples. Fe3O4@MIL‐101(Cr)@NH2 is an efficient sorbent material specially designed for MSPE, which profoundly extracted nine parabens within a short span of just 6 min, driven by π–π interaction and hydrogen bonding. And a detailed optimization and LC–MS/MS analysis was carried out. Fe3O4@MIL‐101(Cr)@NH2 exhibited superior extraction efficiency, enabling subsequent quantification via LC–MS/MS. The limit of detection ranged from 0.063 to 0.622 ng mL−1 and limit of quantification of 0.211 to 2.073 ng mL−1 were a good recovery in the range of 76.2%–108%. An effective detection of eight parabens in chili powder and four parabens in facial toner samples was determined indicating that Fe3O4@MIL‐101(Cr)‐NH2 sorbents are suitable for MSPE. [ABSTRACT FROM AUTHOR]

In this study, the attapulgite nanoparticle was immobilized on the surface of magnetic nanoparticle Fe3O4 via a novel surface covalent reaction method for the magnetic solid phase extraction (MSPE) for the first time. The surface covalent reaction method has the advantages of controllable steps, and can make the magnetic attapulgite nanoparticle (MANP) have good homogeneity and high stability. Field emission scanning electron microscopy, equipped with an energy dispersive spectrometer, Nitrogen adsorption BET, X-ray diffraction and Fourier transform infrared spectroscopy were applied to characterize the prepared MANP, confirming that the attapulgite nanoparticle could be effectively immobilized on the surface of magnetic nanoparticle Fe3O4 via covalent reactions. Under optimal conditions of the MSPE experiment based on the MANP, the limits of detection were found to be 10 ng/mL for melamine and 3 ng/mL for cyromazine with a relative standard deviation < 10% by a high-performance liquid chromatography system. Meanwhile, 0.1 mg/mL melamine in milk and 0.1 mg/mL cyromazine in cucumber can also be detected according to our MSPE procedure. More importantly, the MANP still has good magnetism and enrichment efficiency after several decades of use. These results showed that the MANP prepared by our method is a kind of promising material for the MSPE. [ABSTRACT FROM AUTHOR]

Spilanthol is a major N-alkylamide constituent of Acmella oleracea (L.) R.K. Jansen with diverse pharmacological properties. We recently showed the applicability of NADES (natural deep eutectic solvents) for the green extraction of spilanthol. However, the purification of targets from NADES poses a challenging step due to their non-volatility. A simple green method to retrieve spilanthol with minimal instrumental effort was devised, fractioning NADES (choline chloride/methylurea, choline chloride/1,2-propanediol, choline chloride/citric acid) and dry ethanolic extracts by SPE on C18 material, eluting merely with ethanolic solutions. The relative distribution of spilanthol and organic adulteration in SPE fractions were detected by HPLC-DAD, followed by scale-up, quantification and purity determination in an NMR-based approach. Isocratic elution with 52% ethanol (v/v) proved suitable in all experiments. The three purest 10 mL fractions combined yielded 12.21 mg spilanthol at 71.65% purity from NADES extract ChCl/P (choline chloride/1,2-propanediol, molar ratio 1:2, +20% m/m water). Ethanolic extract samples showed purities ranging from 77.27 to 80.27% in combined raw fractions. For all samples, purity increased by removing non-soluble substances from organic solutions. Pooled NADES extract fractions showed 89.71% in final samples, ethanolic extracts 87.25 to 91.93%. The highest purities of individual fractions per extract were 89.23 to 94.15%. This cheap and simple purification process is promising to acquire spilanthol for research purposes or as a sample preparation step before HPLC on a semi-preparative to preparative scale, as the substance is highly priced and scarcely available on the market. Organic solvents can be reused, and preliminary scale-up possibilities are shown. [ABSTRACT FROM AUTHOR]

This work focuses on the development of a hybrid material based on SBA-15 silica with a molecularly imprinted polymer (MIP), using spiramycin (SPI) as a template, for use as sorbent in solid-phase extraction (SPE). Characterization techniques such as nitrogen gas adsorption–desorption isotherms, infrared spectroscopy and scanning electron microscopy confirmed the structure and properties of the SBA-15@MIP-SPI material. SPE conditions using SBA-15@MIP-SPI as sorbent were optimized, which allowed us to demonstrate the high selectivity and adsorption capacity of SPI on the synthesized material. The best conditions were 50 mg of sorbent, loading with 1 mL of standard solution or sample of cow milk previously extracted in acetonitrile and eluting with 3 mL of methanol with 1% acetic acid. After the optimization process, the material demonstrated recovery percentages of 81 ± 3% in SPI standard solutions and showed its potential in cow milk samples (71 ± 6%). The novelty of the research consists of the combination of MIPs with SBA-15, which could offer important advantages in terms of specific surface area and porous structure, thus improving performance and reducing the amount of sorbent compared to other traditional methods. [ABSTRACT FROM AUTHOR]

Ciguatoxins (CTXs) are neurotoxic marine biotoxins capable of contaminating marine organisms. Approximately 30 CTX analogues have been described; however, only a few have been documented in ciguatera poisoning (CP) outbreaks. Detecting CTXs from complex matrices at CP-relevant concentrations (<1 µg per kg seafood tissue) is analytically challenging. Analytical standards for CTXs are rare. Even after multi-step sample preparation (including liquid–liquid partition, defatting, and solid-phase extraction (SPE)), extracts can contain undesirable co-eluting matrix components. These limitations can exacerbate discrepancies between results obtained by LC-MS/MS and the N2a-bioassay, which are two common CTX detection methods. Herein, a rapid and simple fractionation method, based on normal phase SPE (silica), is demonstrated. Target CTXs were eluted using solvent mixtures of ascending polarity, passed through the column, and separated into eight fractions. To challenge the method, extracts with eleven naturally incurred CTX analogues among different structural CTX groups (e.g., CTX3C, CTX4A, and C-CTX group) were used. The most complex tissue matrix tested (viscera) was improved the most for extract purity and CTX detection, enhancing the correlation between LC-MS/MS and N2a-bioassay results. This workflow represents an advancement for characterizing CTXs in seafood products and CP outbreaks, irrespective of the responsible CTX analogue and where standards are lacking. [ABSTRACT FROM AUTHOR]

An LC–Orbitrap–HRMS method was developed and validated for the simultaneous determination of four tetracyclines—oxytetracycline (OTC), tetracycline (TC), doxycycline (DC), and chlortetracycline (CTC)—in milk. This method involves sample extraction with McIlvaine–EDTA buffer solution (pH 4) and solid-phase extraction (SPE) with Oasis HLB cartridges, followed by the evaporation of the extract and its reconstitution with a 14% methanol aqueous solution before injection into the instrumental system. This method has been validated in terms of linearity, sensitivity, selectivity, precision, and accuracy, in accordance with Commission Decision 2002/657/EC requirements. Compared to existing methods, this approach optimally combines a quantitative procedure for extracting analytes from the milk of different species, including sheep, bovines, and goats, with a very short LC–Orbitrap–HRMS instrumental analysis time (only 8 min), simultaneously ensuring high precision, sensitivity, and applicability as a rapid confirmation method in official food control laboratories. The proposed method was applied to determine the concentration levels of OTC in milk samples derived from healthy Sardinian sheep and those naturally infected with Streptococcus uberis, after the intramuscular administration of an antibiotic, in order to evaluate how much of the drug was "subtracted" during penetration from blood into milk, with a potential effect of reducing its therapeutic efficacy. [ABSTRACT FROM AUTHOR]

Oxytocin and cortisol (OXY and CORT) are hormones related to stress, cognitive, and social behaviors. Their detection is relevant to epidemiological studies aimed at investigating the effects of stressor factors on human life. The aim of this study was to develop and validate an assay for the measurement of OXY and CORT in saliva samples using liquid chromatography/tandem mass spectrometry (LC-MS/MS) in the presence of deuterated analogs. A 500 mL aliquot of oral fluid, obtained by the centrifugation of a chewed swab, was purified by solid-phase extraction. Analytes were then separated using C18 reversed-phase chromatography, subjected to positive electrospray ionization, and then quantified using a triple-quadrupole mass detector in multiple-reaction monitoring mode. The limits of quantification and the linear dynamic ranges were 2.0 × 10−3 and 0.5 nmol/L, and up to 1.0 × 10−1 and 20 nmol/L for OXY and CORT, respectively. Inter- and intra-run precision, expressed as relative standard deviation, was <7%, and accuracy was within 93–104% of the theoretical concentrations. The evaluation of matrix effects showed that the use of internal standards controlled sources of bias. The high sensitivity of the method allowed the quantification of OXY and CORT in the salivary samples of both adults and children: levels of CORT ranged from 0.6 to 18.5 nmol/L, while OXY levels were two orders of magnitude lower (from 1.7 × 10−3 to 1.1 × 10−2 nmol/L). To our knowledge, this is the first method that can analyze, in the same chromatographic run, both hormones in saliva samples. [ABSTRACT FROM AUTHOR]

To determine the paclitaxel-related substances in a paclitaxel injection (albumin-bound), it is necessary to remove human blood albumin from the sample via solid-phase extraction and subsequently perform high-performance liquid chromatography analysis. The pre-processing operation is complicated, the duration of analysis is long, and much human power and material resources are needed in the sample testing process. Thus, the purpose of this study was to develop a quick two-dimensional liquid chromatography method that requires less consumables and possesses high sensitivity. Samples were directly injected into one-dimensional solid-phase extraction columns to remove human blood albumin. Paclitaxel and its related substances in the solid-phase extraction columns were then eluted into two-dimensional analytical columns through valve switching technology. The sample pretreatment step can be omitted in this method, which allows for the analysis of paclitaxel and its related substances to be completed more quickly, within only 15 min, under the developed two-dimensional elution conditions. The established method had good linearity (R2 = 0.9994), limit of detection (0.25 μg·mL−1), limit of quantification (0.5 μg·mL−1), precision (RSD = 0.5%), and accuracy (102.53–107.97%). [ABSTRACT FROM AUTHOR]

A novel magnetic nanomaterial with Fe3O4 as the core, PS-DVB as the shell layer, and the surface modified with C18 (C18−PS−DVB−Fe3O4) had been synthesized by seeded emulsion polymerization. C18−PS−DVB−Fe3O4 retains the advantages of the chemical stability, large porosity, and uniform morphology of organic polymers and has the magnetic properties of Fe3O4. A simple, flexible, and efficient magnetic dispersive solid phase extraction (Mag-dSPE) method for the extraction of preservatives, sweeteners, and colorants in river water was established. C18−PS−DVB−Fe3O4 was used as an adsorbent for Mag-dSPE and was coupled with high-performance liquid chromatography (HPLC) to detect 11 food additives: acesulfame, amaranth, benzoic acid, tartrazine, saccharin sodium, sorbic acid, dehydroacetic acid, sunset yellow, allura red, brilliant blue, and erythrosine. Under the optimum extraction conditions, combined with ChromCoreTMAQC18 (5 μm, 4.6 × 250 mm), 20 mmol/L ammonium acetate aqueous solution and methanol were used as mobile phases, and the detection wavelengths were 240 nm and 410 nm. The limits of detection (LODs) of 11 food additives were 0.6–3.1 μg/L with satisfactory recoveries ranging from 86.53% to 106.32%. And the material could be reused for five cycles without much sacrifice of extraction efficiency. The proposed method has been used to determine food additives in river water samples, and results demonstrate the applicability of the proposed C18−PS−DVB−Fe3O4 Mag-dSPE coupled with the HPLC method to environment monitoring analysis. [ABSTRACT FROM AUTHOR]

The advancement of traditional sample preparation techniques has brought about miniaturization systems designed to scale down conventional methods and advocate for environmentally friendly analytical approaches. Although often referred to as green analytical strategies, the effectiveness of these methods is intricately linked to the properties of the sorbent utilized. Moreover, to fully embrace implementing these methods, it is crucial to innovate and develop new sorbent or solid phases that enhance the adaptability of miniaturized techniques across various matrices and analytes. Graphene-based materials exhibit remarkable versatility and modification potential, making them ideal sorbents for miniaturized strategies due to their high surface area and functional groups. Their notable adsorption capability and alignment with green synthesis approaches, such as bio-based graphene materials, enable the use of less sorbent and the creation of biodegradable materials, enhancing their eco-friendly aspects towards green analytical practices. Therefore, this study provides an overview of different types of hybrid graphene-based materials as well as their applications in crucial miniaturized techniques, focusing on offline methodologies such as stir bar sorptive extraction (SBSE), microextraction by packed sorbent (MEPS), pipette-tip solid-phase extraction (PT-SPE), disposable pipette extraction (DPX), dispersive micro-solid-phase extraction (d-µ-SPE), and magnetic solid-phase extraction (MSPE). [ABSTRACT FROM AUTHOR]

The irrigation of soils with reclaimed contaminated wastewater or its amendment with sewage sludge contributes to the uptake of pharmaceuticals by vegetables growing in the soil. A multiresidue method has been devised to determine five pharmaceuticals and nine of their main metabolites in leafy and root vegetables. The method employs ultrasound-assisted extraction, clean-up via dispersive solid-phase extraction, and analysis through liquid chromatography–tandem mass spectrometry. Box–Behnken design was used to refine variables such as extraction solvent volume, time of extraction, number of extraction cycles, and the type and amount of d-SPE sorbent. The method achieved linearity (R2) greater than 0.994, precision (relative standard deviation) under 16% for most compounds, and detection limits ranging from 0.007 to 2.25 ng g−1 dry weight. This method was applied to a leafy vegetable (lettuce) and to a root vegetable (carrot) sourced from a local market. Parent compounds were detected at higher concentrations than their metabolites, with the exception of carbamazepine-10,11-epoxide. [ABSTRACT FROM AUTHOR]

For the first time, a highly permeable nanoporous carbon derived from melamine-based polybenzoxazine (NPC-PBZ-m) was used as the solid-phase extraction sorbent for trace analysis of atrazine (ATZ) herbicide in environmental water samples as a pre-treatment to enhance detection for high-performance liquid chromatography. Extraction performance was investigated using an agricultural field matrix-water sample. The parameters affecting the solid-phase extraction efficiency were carefully investigated. The optimisation conditions were determined as 200.0 mg of sorbent with an adsorption flow rate of 10.0 mL min−1, an elution flow rate of 1.0 mL min−1, and an elution volume of 3.0 mL. Moreover, it was not necessary to adjust the pH of the sample. Under these optimised extraction conditions, good linearity between 5.00 and 30.0 µg L−1 was achieved along with a limit of detection (LOD) of 1.25 µg L−1 and a limit of quantification (LOQ) of 3.79 µg L−1. Furthermore, the reusability of the NPC-PBZ-m column was found up to 8 cycles making it a new cost-effective material for herbicide enrichment. Finally, this developed method was successfully applied to analyse ATZ in water samples from rice fields, fish farms, and natural canal water, with 98–117% relative recoveries. These results indicate that NPC-PBZ-m with our proposed method is feasible and demonstrates its potential application as an effective adsorbent for herbicide enrichment. [ABSTRACT FROM AUTHOR]

Diamide insecticides represent a class of highly efficient compounds that have been widely employed in plant protection in recent years. The potential risk of exceeding residue limits in agricultural products should not be disregarded but the molecular structure of diamides dictates that the currently widely used QuEChERS cannot be extended to the analysis of their residues in food. The aim of this work is to develop a multi-residue method for diamides in vegetables using an alternative to traditional plant pigment removers. A modified QuEChERS based on the recently reported pigment remover Carbon S was established, and a multi-residue method for the determination of six diamide insecticides (flubendiamide, chlorantraniliprole, cyantraniliprole, tetrachlorantraniliprole, cyclaniliprole, and broflanilide) in melons and leafy vegetables using ultra-performance liquid chromatography with photodiode array detector (UPLC-PDA) was developed. The evaluation of this methodology showed the recoveries of the diamides in the vegetable matrices ranged from 80 to 107%, with intra- and inter-day relative standard deviations (RSDs) of less than 10%. The limits of quantification (LOQs) for these insecticides in vegetables were from 0.034 to 0.051 mg/kg. The modified QuEChERS employing carbon S exhibits environmental friendliness, high efficiency, and good reproducibility. The optimized methodology demonstrates accuracy, sensitivity, and reliability. Carbon S was used as a plant pigments remover, extending the application of QuEChERS to the determination of diamide residues in vegetables. [ABSTRACT FROM AUTHOR]

Buprenorphine is one of the most commonly used pain-killing drugs due to its lengthy duration of action and high potency. However, excessive usage of buprenorphine can be harmful to one's health and prolonged use might result in addiction. Additionally, an increasing number of cases have been documented involving the illegal use of buprenorphine. Therefore, a variety of effective and reliable methods for pretreatment and determination of buprenorphine and its main metabolite norbuprenorphine have been established. This review aims to update the current state of pretreatment and detection techniques for buprenorphine and norbuprenorphine from January 2010 to March 2022. Pretreatment methods include several traditional extraction methods, solid-phase extraction, QuECHERS, various micro-extraction techniques, etc. while analytical methods include LC-MS, LC coupled with other detectors, GC-MS, capillary electrophoresis, electrochemical sensors, etc. The pros and cons of various techniques were compared and summarized, and the prospects were provided. HIGHLIGHTS: Progress in pretreatment and detection methods for buprenorphine is demonstrated. Pros and cons of different pretreatment and analysis methods are compared. New materials (such as nanomaterials and magnetic materials) used in buprenorphine pretreatment are summarized. Newly emerged environmental-friendly methods are discussed. [ABSTRACT FROM AUTHOR]

A novel 3D magnetic nanocomposite material based on covalent organic polymers was successfully synthesized and utilized as an efficient sorbent for magnetic solid-phase extraction. It exhibited a regular core–shell structure, large specific surface area, superior stability, and paramagnetism. To evaluate its extraction efficiency, six flavonoids were tested, demonstrating maximum adsorption capacities ranging from 90 to 218 mg/g. Additionally, the material exhibited remarkable reusability and mechanical stability, maintaining its original state over eight cycles with consistent recovery. An analytical strategy combining magnetic solid-phase extraction with high performance liquid chromatography and tandem mass spectrometry was developed for the determination of flavonoids in orange, honey, soybean, and Dioscorea bulbifera L. samples. The low limits of detection (0.01–0.1 ng/mL) and limits of quantification (0.05–0.5 ng/mL), as well as satisfactory recovery (80.4–114.8%), were obtained. The linear range started from the limits of quantification to 500 ng/mL with R2 ≥ 0.9929. These results suggest that the prepared adsorbent possesses excellent adsorption capabilities for flavonoids, highlighting its significant potential for detecting these compounds in complex sample matrices. [ABSTRACT FROM AUTHOR]

A novel magnetic dispersive solid phase extraction (MDSPE) procedure based on the deep eutectic solvent (DES) modified magnetic graphene oxide/metal organic frameworks nanocomposites (MGO@ZIF-8@DES) was established and used for the efficient enrichment of estradiol, estrone, and diethylstilbestrol in cosmetics (toner, lotion, and cream) for the first time. Then, the three estrogens were separated and determined by UHPLC-UV analysis method. In order to study the features and morphology of the synthesized adsorbents, various techniques such as FT-IR, SEM, and VSM measurements were executed. The MGO@ZIF-8@DES nanocomposites combine the advantages of high adsorption capacity, adequate stability in aqueous solution, and convenient separation from the sample solution. To achieve high extraction recoveries, the Box-Behnken design and single factor experiment were applied in the experimental design. Under the optimum conditions, the method detection limits for three estrogens were 20–30 ng g−1. This approach showed a good correlation coefficient (r more than 0.9998) and reasonable linearity in the range 70–10000 ng g−1. The relative standard deviations for intra-day and inter-day were beneath 7.5% and 8.9%, respectively. The developed MDSPE-UHPLC-UV method was successfully used to determine three estrogens in cosmetics, and acceptable recoveries in the intervals of 83.5–95.9% were obtained. Finally, three estrogens were not detected in some cosmetic samples. In addition, the Complex GAPI tool was used to evaluate the greenness of the developed pretreatment method. The developed MDSPE-UHPLC-UV method is sensitive, accurate, rapid, and eco-friendly, which provides a promising strategy for determining hormones in different complex samples. [ABSTRACT FROM AUTHOR]

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An airlift reactor with the external loop (EXL ALFR) is a widely used modified version of a Bubble Column Reactor (BCR). An EXL ALFR can also be used for a three-phase system with the solid phase in a packed or fluidized form. An EXL ALFR provides design flexibility for conventional chemical reactions as well as biological reactions. Shear is an important factor for the reactors handling immobilized enzymes. In the current investigation, the effect of the design variables, like gas hold-up, the velocity of circulating liquid, and the distribution of bubble dimension, was compared for an EXL ALFR and an external loop airlift reactor with a packed bed (EXL ALFR-PB). Particle Image Velocimetry (PIV) was employed for the liquid axial velocity in the downcomer of the reactors, and the computational fluid dynamic with the Population Balance Model (CFD-PBM) was employed. The minimum percentage of errors of 2.3% and 1.2% and the maximum of 4.2% and 3.4% were obtained for the experimental and predicted values of gas hold-up in the EXL ALFR and EXL ALFR-PB, respectively. For the velocity of the circulating liquid, the predicted and experimental values of their minimum percentage error were 1.1% and 0.5% and a maximum of 4.3% and 4.5% in EXL ALFR and EXL ALFR-PB, respectively. Also, the pressure drops calculated from the Ergun equation and CFD simulation had a 0 to 4% difference, indicating good agreement. [ABSTRACT FROM AUTHOR]

UV filters and benzotriazole UV stabilizers are considered emerging contaminants in the environment. LC–MS/MS and GC–MS methods, involving a single solid phase extraction protocol, were developed and validated to determine eight UV filters and seven UV stabilizers, respectively in wastewater from a wastewater treatment plant (WWTP) in Lüneburg, Germany. The LC–MS/MS method exhibited extraction recoveries of ≥ 71% at six different fortification levels with limits of detection (LODs) range of 0.02 ng mL−1 – 0.09 ng mL−1. Extraction recoveries of 47 to 119% at six different fortification levels were obtained for the GC–MS method with LODs range of 0.01 – 0.09 ng mL−1. Among the UV filters, the highest mean concentration was determined for octocrylene (OCR) in influent (3.49 ng mL−1) while the highest mean concentration was measured for 2-hydroxy-4-octyloxybenzophenone (UV 531) in influent (0.44 ng mL−1) among the UV stabilizers. Potential risk to aquatic organisms was assessed by the risk quotient approach. Only OCR presented a high risk to aquatic invertebrates whereas 2-ethylhexyl 4-methoxycinnamate (EHMC) and 2-ethylhexyl salicylate (EHS) posed high risks to algae. Benzotriazole UV stabilizers presented negligible risks to aquatic invertebrates and fish. This work reports the detection of rarely studied 4-aminobenzoic acid (PABA) and UV 531 in WWTP influent and effluent. The occurrence and risk assessment of target benzotriazole UV stabilizers in wastewater from a German WWTP was demonstrated for the first time. [ABSTRACT FROM AUTHOR]

Glyphosate is the most used herbicide in agriculture. Its major metabolite is AMPA (aminomethylphosphonic acid), but N-acetyl-AMPA and N-acetylglyphosate are also metabolites of interest. For risk assessment, a general residue definition was proposed as the sum of glyphosate, AMPA, N-acetyl-glyphosate and N-acetyl-AMPA, expressed as glyphosate. A confirmatory method for glyphosate in fat, liver and kidneys, as well as a confirmatory method for AMPA and N-acetyl-glyphosate in all matrices, are still missing. In this paper, we present a method for the quantitative determination of glyphosate residues and its metabolites AMPA, N-acetyl-AMPA and N-acetyl-glyphosate by liquid chromatography–mass spectrometry (LC-MS/MS) in adipose tissue, liver, eggs, milk and honey without derivatization. Different chromatographic columns were tested, with the Hypercarb column providing the best results. The analytes were eluted with mobile phases of acidified water with 1.2% formic acid and 0.5% formic acid in acetonitrile. Sample purification procedures were also optimized by varying the solvent extraction mixtures (water, methanol and mixture ψ (methanol, water) = 1:1, each with the addition of 1% formic acid (v/v)), using different sorbents in solid phase extraction (SPE) (polymeric cationic (PCX) and anionic (PAX)) and using dispersive solid phase extraction (dSPE) (C18 and PSA) by modifying the extraction procedures. Finally, the analytes were extracted from the samples with 1% formic acid in water (v/v). Milk and adipose tissue were purified by the addition of dichloromethane, while liver and egg samples were purified by SPE with a mixed cation exchange sorbent and ultrafiltration with cut-off filters. The proposed analytical procedures were validated according to SANTE/11312/2021 guidelines: linearity, limits of quantification, precision and accuracy were determined for all matrices. The limits of quantification (LOQs) ranged from 0.025 to 0.2 mg kg−1. Precision, expressed as relative standard deviation, was <20%, while accuracy, expressed as analytical recovery, ranged from 70% to 120%. During method validation, the measurement uncertainty was estimated to be <50% for all analytes. Good validation parameters according to the SANTE document were achieved for all analytes. Therefore, the method can be considered reliable and sensitive enough for routine monitoring of polar pesticides. The application of the accredited method in routine analysis will provide data that are useful for the re-evaluation of risk assessment studies in foods of animal origin. [ABSTRACT FROM AUTHOR]

The gut microbiome, crucial to human health, changes with age and disease, and influences metabolic profiles. Gut bacteria produce short-chain fatty acids (SCFAs), essential for maintaining homeostasis and modulating inflammation. Dysbiosis, commonly due to poor diet or lifestyle, disrupts the integrity of the intestinal barrier and may contribute to conditions such as obesity, diabetes, and non-alcoholic fatty liver disease (NAFLD). Analytical methods such as gas chromatography–mass spectrometry (GC/MS) are vital for SCFA analysis, with various preparation and storage techniques improving the accuracy. Advances in these methods have improved the reliability and sensitivity of SCFA quantification, which is crucial for the identification of disease biomarkers. Evidence from GC/MS-based studies has revealed that accurate SCFA quantification requires meticulous sample preparation and handling. The process begins with the extraction of SCFAs from biological samples using methods such as direct solvent extraction or solid-phase microextraction (SPME), both of which require optimization for maximum recovery. Derivatization, which chemically modifies SCFAs to enhance volatility and detectability, is a crucial step, typically involving esterification or silylation. Following this, the cleanup process removes impurities that might interfere with the analysis. Although recent advances in GC/MS technology have significantly improved SCFA-detection sensitivity and specificity, proper sample storage, with acid preservatives and the avoidance of repeated thawing, is essential for maintaining SCFA integrity. [ABSTRACT FROM AUTHOR]

A novel, simple, fast and sensitive method for the simultaneous analysis of heavy metals such as Cd(II), Cr(III), Co(II), Pb(II) and Cu(II) in hair samples based on complexometric method with EDTA and using solid-phase extraction with graphene oxide coupled with capillary electrophoresis has been developed. Under the optimised conditions, the proposed methodology had limits of detection from 5.7 to 16.8 µg kg−1 with intra- and inter-day repeatabilities <5% (in respect to relative standard deviation) in all cases. The proposed method was successfully employed for determination of heavy metals in the analysis of 20 hair samples. All samples were positive for at least one of the heavy metals studied with concentrations of 1.2 ± 1.0 mg kg−1 Cd(II), 7.2 ± 4.0 mg kg−1 Cr(III), 0.9 ± 0.8 mg kg−1 Co(II), 0.6 ± 0.2 mg kg−1 Pb(II) and 2.5 ± 0.3 mg kg−1 Cu(II). The method is an easy, robust and efficient strategy for determination of heavy metals in complex matrices. [ABSTRACT FROM AUTHOR]

Emerging contaminants (ECs) are substances that have no defined environmental quality standards or regulations, and have the potential to pose major adverse impacts on the environment and human health. The detection of contaminants in the natural environment is the key step for establishing precise environmental risk assessment approach for ECs. However, ECs come from different origins with various physicochemical properties, making their detection a complicated process. Moreover, their presence in the aquatic environment at trace concentration range (ng/L-µg/L), requires an accurate detection at low concentration levels. This study aims to develop an efficient analytical method for simultaneous determination of 5 different ECs in aqueous solution based on solid phase extraction technique (SPE) followed by liquid chromatography-mass spectrometry (LC–MS/MS). High recovery rates (72% to 114%) were achieved for all targeted compounds. Ciprofloxacin (CIP), diuron (DIU), terbutryn (TER) and diclofenac (DIC) had a limit of detection (LOD) of 5 µg/L and a limit of quantification (LOQ) of 10 ng/L, while LOD and LOQ for EE2 were 25 µg/L and 50 ng/L, respectively. These results confirm that the optimized method can be applied for extraction and analysis of ECs from different classes in the aquatic environment. [ABSTRACT FROM AUTHOR]