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Both sedative and antipathogenic drugs are often found to be illegally used in aquaculture, but there is a lack of simultaneous monitoring methods. A method for simultaneously monitoring multiple prohibited drugs in various aquatic product samples was developed in this work, including fish, shrimp, crab, and shellfish. Sulfonic acid-functionalized magnetic graphitic carbon nitride (S-MGCN) was synthesized and validated to efficiently co-extract all targets (adsorption efficiency over 90.07%) through various adsorption mechanisms such as electrostatic interaction, hydrogen bonding, and π-π interaction while demonstrating good sample matrix purification ability (matrix effect below 13.60%). A new magnetic solid-phase extraction method based on S-MGCN was subsequently established. Coupled with UPLC-MS/MS, the detection limits were 0.030.075 μg /kg, and the recoveries ranged from 88.76% to 111.74% with the RSDs lower than 14.60%, indicating that the developed method has good sensitivity, accuracy, and precision. Further validation of its practicality was achieved through actual sample analysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A 3-step load-wash-elute solid-phase extraction tandem dedicated clean-up cartridge prior to UPLC-MS/MS for the simultaneous determination of bongkretic acid, isobongkretic acid and toxoflavin in food is presented in this work. The 3-step load-wash-elute SPE strategy with PRiME HLB, eliminating conditioning and equilibration, and coupled with dedicated purification cartridge, PriboFast MFC 336, was used as a tandem cartridge for sample pretreatment. Various sample pretreatment conditions including sample extractant, the tandem cartridge, the optimizatioin of PRiME HLB SPE conditions and PriboFast MFC 336 purification conditions, as well as MS/MS conditions and HPLC conditions were systematically investigated. Under the optimal experimental conditions, high sensitivity (LODs: 0.030-0.040 μg kg -1 , LOQs: 0.090-0.12 μg kg -1 ), acceptable recoveries (83 %-96 %) and good precisions (r 2  < 6.0 %) were obtained. The method was successfully applied to 90 food samples, bongkretic acid and isobongkretic acid were detected simultaneously in a dried black fungus, whereas toxoflavin was not detected in any of the samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Co-extraction of multiple types of target substances is the key to achieve high throughput detection. In this work, PDA@MOF-808/PAN NFsM was prepared by co-modified polyacrylonitrile nanofiber membrane (PAN NFsM) with polydopamine (PDA) and metal-organic framework-808 (MOF-808), and its potential as a solid-phase extraction (SPE) adsorbent was investigated by using the most typical nine veterinary drug residues in eggs and chicken as model target substances. The results show that PDA@MOF-808/PAN NFsM could effectively co-extract all the target substances (adsorption efficiency ranged from 81.46 % to 96.78 %), and had good capability of sample matrix purification (matrix effect was lower than -15.26 %), so a new SPE method has been established. Combined with UPLC-MS/MS, the detection limits were 0.3 to 3.1 μg/kg, the recoveries were between 71.02 % and 106.48 %, and the relative standard deviations were lower than 12.03 %, indicating that the method has considerable good sensitivity, accuracy and precision., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Quaternary phosphonium compounds (QPCs) and phosphine oxides (POs) are emerging contaminants that are attracting increasing attention. In the present study, a method for the quantification of QPCs and POs in multiple environmental media was developed using ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Analytes were extracted from water samples using solid phase extraction, and for the solid samples, ultrasonic extraction was employed. Compared with analytical methods established by previous studies, the approach developed in this study is more suitable for the quantitative analysis of compounds along with high sensitivity. The method quantification limit reached 0.12-2.55 ng⋅L -1 in water samples and 0.004-0.10 ng⋅g -1 in solid samples. The recoveries of target analytes spiked at low, medium and high concentrations in water and solid samples were in the range of 56.4-120 %, with relative standard deviations below 20 % (n = 6). Furthermore, the validated method succeeded in applying to analyse of eight QPCs and four POs in real environmental samples. At least five QPCs and two POs were detected in each environmental medium. This quantitative method would assist in further investigations on the occurrence, migration and the source of QPCs and POs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Herein, a magnetic cationic Schiff base polymeric material (Fe 3 O 4 @SiO 2 -Schiff-TAPB-DA) was fabricated simply and rapidly, which was explored as a magnetic adsorbent for magnetic solid-phase extraction (MSPE) for enriching seven avermectins insecticides in surface water and milk matrices combined with ultra-high performance liquid chromatography mass spectrometry (UPLC-MS/MS). Under the optimized pretreatment and instrumental parameters, the analytes showed good linearity in the range of 0.5-200.0 ng·mL -1 with a correlation coefficient (R 2 ) greater than 0.9990 and high precision. The limits of detection for the analytes were 0.004-0.047 μg·L -1 for surface water sample and 0.008-0.250 μg·kg -1 for milk samples. Satisfactory recoveries of spiked target compounds were in the range of 82.25- 100.87 % for surface water sample and 72.73- 119.62 % for milk samples. The results indicated powerfully Fe 3 O 4 @SiO 2 -Schiff-TAPB-DA was of significant potential as an MSPE adsorbent for the detection of avermectin insecticides in surface water and milk, which provides a quick and efficient idea for enriching avermectins insecticides in complicated matrices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Wastewater-based epidemiology (WBE) has become an objective and updated surveillance strategy for monitoring and estimating consumption trends of psychoactive substances (PSs) in the population. Firstly, magnetic shrimp shell biochar-based adsorbent (DZMBC) was synthesized and employed for extraction trace PSs from municipal wastewater. Proper pyrolysis temperature and increased KOH activator content favored the pore structure and surface area, thus facilitating extraction. DZMBC delivered exceptional extraction performance such as pH stability, anti-interference property, fast magnetic separation ability, reusability, and reproducibility. Then, a method based on magnetic solid-phase extraction (MSPE) followed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed, validated, and utilized for the quantitative determination of five PSs in real wastewater samples. Methodological validation results indicated a favorable linearity, low method limits of detection (1.00-4.75 ng/L), and good precisions (intra-day and inter-day relative standard deviations < 4.8%). Finally, an objective snapshot of Chongqing drug use and consumption pattern was obtained. Methamphetamine (MAMP) and 3,4-methylenedioxymethamphetamine (MDMA) were the prevalent illegal drugs in local. Both concentrations and per capita consumption of MDMA displayed a change (P < 0.05) between July and September, while no statistical differences were observed for each week., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Traditional solid-phase extraction (SPE) LC-MS/MS is limited by high costs, turnaround times, and procedural complexity, which limited the usage in clinical practice. This study aimed to establish a robust UPLC-MS/MS method with automated magnetic-bead-assisted sequential extraction (MBASE) technology to simultaneously measure Aβ1-42 and Aβ1-40 in cerebrospinal fluid (CSF). A Waters TQ-XS triple quadrupole mass spectrometer and Acquity UPLC Protein BEH C4 column were used. The targeted analytes were extracted and concentrated using the automated MBASE technology with chemically modified magnetic MCX beads. Analytical performance was verified referring to the CLSI C62-A and EP-15-A3 guidelines. A total of 68 CSF samples were collected and analyzed using the MBASE UPLC-MS/MS method, traditional SPE UPLC-MS/MS method, and Lumipulse G fully automated chemiluminescence detection system, and method comparison analysis is conducted. The MBASE UHPLC-MS/MS method showed an analytical performance equivalent to that of traditional SPE technology, with a higher sample throughput and smaller amount of materials ($34.98 vs. $493.96) and labor cost (101 min vs. 140 min) for 96 samples. The limit of quantification (LOQ) of Aβ1-42 and Aβ1-40 was 0.10 ng/mL and 0.05 ng/mL; recovery was 88.35-107.07 % and 95.72-96.60 %; and total imprecision was 3.69-6.83 % and 3.02-3.61 %, respectively. The measurements were faithfully reproduced within the allowable levels of uncertainty using certified reference materials. The correlations between this MBASE UPLC-MS/MS method, the SPE UPLC-MS/MS method, and Lumipulse G fully automated biochemical analysis method are all deemed good (r = 0.869-0.936), and the MBASE- and SPE-UPLC-MS/MS methods showed comparable measurements. To our knowledge, our study firstly verified the robust performance of the MBASE UPLC-MS/MS method to simultaneously determine Aβ1-42 and Aβ1-40 in CSF. With further introduce of automation, the assay with high accuracy and low material and labor costs will become a promising clinical technology., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have ppeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A new green method for trace level quantification of four herbicides, glyphosate (GLYP), glufosinate (GLUF), and their main metabolites, aminomethylphosphonic acid (AMPA) and 3-(methyl-phosphinico)-propionic acid (MPPA), was developed. The purification step without any derivatization was conducted by solid-phase extraction using Chelex-100 resin in the Fe (III) form, followed by elution with 5% NH 4 OH. The four analytes were quantified by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry. The developed extraction method was validated on five fresh and sea water matrices with mean recoveries ranging from 80.1% to 109.4% (relative standard deviation < 20%). The extraction conditions were evaluated and certified for the high applicability of the extraction method too. The limits of detection (ng/L) in the five water matrices were in ranges 0.70 - 4.0, 2.4 - 3.9, 1.8 - 4.7, and 1.6 - 4.0 for GLYP, AMPA, GLUF, and MPPA, respectively. The method was successfully applied to detect the four compounds in surface waters sampled along the Red River Delta region in July 2019. The highest concentrations were detected at 565, 1,330, 234, and 871 ng/L for GLYP, AMPA, GLUF, and MPPA, respectively. These results showed the potential capacity of this new method for convenient monitoring of herbicides and their metabolites in the diverse natural water system., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The current study developed a cheap and effective method for the simultaneous extraction of 14 heterocyclic aromatic amines (HAAs) in food matrix. Core-shell Fe 3 O 4 @PDA nanoparticles were constructed and acted as the magnetic solid-phase extraction adsorbent to separate and purify HAAs from meat products for the first time. Then, UPLC-MS/MS technique was employed to identify and quantify the HAAs easily. Fe 3 O 4 @PDA nanoparticles were synthesized and characterized successfully. Totally 14 HAAs were completely separated in 19.99 min with good regression coefficients. LODs and LOQs were in the range of 0.013-0.247 ng/g and 0.056-0.803 ng/g, respectively. The intra-day precisions and inter-day precisions were below 9%. Except for IQ[4,5-b], Phe-p-1, PhIP, other 11 types of HAAs (DMIP, 1,5,6-TMIP, IQ, IQx, MeIQ, MeIQx, 7,8-DiMeIQx, AαC, MeAαC, Harman, Norharman) could acquire relatively high recoveries (71.06%-108.49%). The proposed method was successfully devoted to the evaluation of HAAs levels in 8 commercial meat products to verify the adaptability., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this work, sodium 4-styrenesulfonate functionalized polyacrylonitrile nanofibers mat (SS/PAN NFM) was firstly prepared and applied as 96-well plate solid-phase extraction adsorbent for quantitative determination of seven β-agonists residues in pork samples. The functional modification endowed the SS/PAN NFM with superior adsorption performance for target β-agonists. The adsorption process is spontaneous (ΔG < 0), the initial adsorption rate can reach 6.03-9.09 mg/g/min and the maximum adsorption capacity is calculated to be 48.3 mg/g at 298 K. Moreover, SS/PAN NFM can be reused for 12 times without degradation in adsorption capability. Combined with UPLC-MS/MS, the limits of detection can reach 0.006-0.24 μg/kg, the recoveries ranged from 87.2% to 111% and the relative standard deviations of intra-day and inter-day precisions were in the scope of 1.75%-11.6% and 5.08%-13.5%, respectively. The obtained results fully demonstrated the practicability of this method in preventing the hazard of β-agonists residues., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Maximum residue limits (MRLs) for pesticides have been established in teas for quality control and protection of consumer health in many countries and regions, including Europe. It is, however, challenging to quantify multi-pesticide residues at low concentrations in complex matrices, such as tea. In this study, highly sensitive, efficient, and rugged analytical methods were adapted for simultaneous determination of 400 pesticide residues in green tea products using ultra performance liquid and gas chromatography coupled to tandem mass spectroscopy (UPLC-MS/MS and GC-MS/MS). Matrix effects were minimized by combining QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction and mixed-mode SPE clean-up with different sorbents in sample preparation. A C18 SPE cartridge paired with SPE GCB/PSA proved to be the most effective clean-up method and enabled 225 pesticide residues to be quantified, based on solvent calibration curves (154 residues using UPLC-MS/MS and 71 residues using GC-MS/MS). The analytical methods were validated fully in accordance with the SANTE/11945/2015. LOQs for most pesticides (386/400 or 96.5%) were below 10 µg/kg, i.e., less than the EU MRL (5-70 mg/kg). Thus, these approaches can be applied for routine analysis of multi-pesticide residues in green tea., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Justicia procumbens is a food and medicine homologous variety, popularly used for making vegetable soups. In this study, a novel mesoporous silica was synthesized and used as the sorbent of SPE for the purification of lignans from J. procumbens. A laboratory-made SPE cartridge was packed with 100 mg of mesoporous silica, which was washed with 10% methanol and eluted using 0.8 mL acetonitrile after sample loading. Afterward, the extract was analyzed by ultra-performance liquid chromatography (UPLC) and MS/MS. All the lignans were efficiently separated in 6 min with the noise level in the range of 50-150 cps. 6'-Hydroxy justicidin B, 6'-hydroxy justicidin A, justicidin B, chinensinaphthol methyl ether, justicidin C, and neojusticdin A were identified to be the dominant molecular species in J. procumbens with contents of 0.065-0.37 mg/g in three tested sample batches from different geographic origins. In conclusion, the proposed mesoporous silica based SPE UPLC-MS/MS method is efficient in linearity (R 2 = 0.9989-0.9996), sensitivity (LOD ≤0.13 μg/kg and LOQ ≤0.42 μg/kg), precision (RSD intra-day ≤3.12 and RSD inter-day ≤4.56), and recovery (83.42-96.11%, RSD ≤2.88%)., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The simultaneous detection of multiple mycotoxins is important due to the increased toxic effects of combined mycotoxins in grains. In this research, a combination of modified QuEChERS with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used for simultaneous detection of 20 mycotoxins in grains. A series of different types of magnetic (Fe 3 O 4 ) nanoparticles modified with multiwalled carbon nanotubes (Fe 3 O 4 -MWCNTs) were designed as modified QuEChERS adsorbents for facile and efficient purification and for target interferences removal in the matrices. When there is an external magnetic field, the proposed modified QuEChERS method uses a shorter pretreatment time compared with the traditional QuEChERS method, which makes it possible to conduct high-throughput analyses. To optimize the QuEChERS process, the extraction solvent and the type and amount of the Fe 3 O 4 -MWCNTs were investigated. Under optimal conditions, the method was validated and showed satisfactory linearity ( r 2 ≥ 0.9965), good recovery (73.5-112.9%), good precision (1.3-12.7%), and excellent sensitivity (ranging from 0.0021 to 5.4457 ng g -1 ), which indicates that this method can be used for detecting multiple mycotoxins in real samples.

One-step solid-phase extraction (SPE) using a multiwalled carbon nanotube (MWCNT) for simultaneous analysis of 21 mycotoxins, including nine trichothecenes, zearalenone (ZEN) and its derivatives, four aflatoxins, and two ochratoxins, in corn and wheat was developed. Several key parameters affecting the performance of the one-step SPE procedure-types of MWCNT, combinations with five sorbents (octadecylsilyl (C 18 ), hydrophilic⁻lipophilic balance (HLB), mixed-mode cationic exchange (MCX), silica gel, and amino-propyl (NH₂)), and filling amounts of the MWCNTs-were thoroughly investigated. The combination of 20 mg carboxylic MWCNT and 200 mg C 18 was proven to be the most effective, allowing the quantification of all analyzed mycotoxins in corn and wheat. Under the optimized cleanup procedure prior to ultraperformance liquid chromatography⁻tandem mass spectrometry (UPLC⁻MS/MS) analysis, the method was validated by analyzing samples spiked at the limit of quantification (LOQ), two-times LOQ, and 10-times LOQ. Satisfactory linearity ( r ² ≥ 0.9910), high sensitivity (LOQ in different ranges of 0.5⁻25 μg L -1 ), good recovery (75.6⁻110.3%), and acceptable precision (relative standard deviation (RSD), 0.3⁻10.7%) were obtained. The applicability of the method was further confirmed using raw samples of corn and wheat. In conclusion, the established method was rapid, simple and reliable for simultaneous analysis of 21 mycotoxins in corn and wheat.

Objective: To develop a method for determination of bisphenol A in human blood by fast phospholipid removal solid phase extraction method-ultra performance liquid chromatography tandem mass spectrometry( UPLC-MS/MS)., Methods: Enzymatic hydrolysis( β-glucuronidase/arylsulfatase) and phospholipid removal solid phase extraction were used to treat the blood samples under the acidic condition, a Infinity Lab Poroshell 120 PFP column( 100 mm × 3. 0 mm, 2. 7 μm) was used for LC separation, ESI negative ion scan was used with multiple reaction monitoring( MRM) mode., Results: The calibration curve was linear in the range of 0. 1-100 ng/mL for bisphenol A with correlation coefficients more than 0. 999. The limit of detection was 0. 05 ng/mL, the limit of quantity was 0. 15 ng/mL. The recoveries of the method for bisphenol A at three spiked levels of 0. 5, 5 and 50 ng/mL ranged from 87. 3%to 112. 1%. The relative standard deviation( RSD) of intra and inter day were range from3. 3%-8. 2%, 4. 9%-10. 7%( n = 6), respectively., Conclusion: The method is successfully applied in the analysis of bisphenol A in human blood with its simple operation, sensitivity and accuracy.

The detection of mycotoxin contamination in foodstuffs is highly significant for public health. Herein we report an analytical method based on magnetic solid-phase extraction (MSPE) and UPLC-MS/MS for the simultaneous determination of mycotoxins, including fumonisins B 1 (FB 1 ), zearalenone (ZON) and ochratoxin A (OTA), in vegetable oil. Magnetic nanoparticles coated with double layers of silicon dioxide were synthesised and found to be an effective MSPE adsorbent for mycotoxins. The proposed MSPE procedure serves not only for sample clean-up but also for mycotoxin enrichment that enhances greatly the assay's sensitivity. Under the selected MSPE conditions, linear matrix-matched calibration curves were obtained for mycotoxins in a concentration range from 0.178 to 625 μg kg -1 . The limits of detection were 0.210 μg kg -1 for FB 1 , 0.0800 μg kg -1 for OTA and 1.03 μg kg -1 for ZON. The proposed MSPE UPLC-MS/MS method was applied for the determination of mycotoxins in vegetable oil samples, including maize oil, rapeseed oil and soybean oil. ZON was detected in a maize oil at 101 μg kg -1 , which is below the European Union limit of 200 μg kg -1 in foodstuffs.

The present work describes a multi-residue SPE-UPLC-MS/MS method aiming at the characterization of 68 compounds in natural waters, including parent compounds as well as their major metabolites and glucuronide conjugates. Development was conducted toward the quantitative determination of a broad range of analytes belonging to different class of psychotropic drugs such as benzodiazepines, antidepressants, stimulants, opiates and opioids, anticonvulsants, anti-dementia drugs, analgesic and anti-inflammatory drugs (as anthropic indicators) in the low ngL -1 range of concentration. Satisfactory extraction recoveries >70% were obtained for the majority of analytes (49 out of 68) allowing low limits of quantification. LOQ ranged between 0.1 and 17.8ngL -1 and were lower than 5ngL -1 for 94% of investigated analytes. Furthermore, addition of 25 isotopic labeled standards allowed to ensure reliability of the optimized method. Quantification errors were typically below 15% with relative standard variations <10% in intermediate precision conditions. Finally, the developed method was implemented in natural waters; sampling campaigns were conducted in the Seine River as a demonstration of the applicability and adequation of the method for its purpose. As a result, 48 out of 68 analytes were identified or quantified; some of them like memantine, rivastigmine, zolpidem 4-phenyl-carboxylic acid, zolpidem 6-carboxylic acid for one of the first time in surface waters. Among investigated psychotropic compounds and metabolites, tramadol, codeine, oxazepam, venlafaxine, O-desmethylvenlafaxine, gabapentin, carbamazepine and 10,11-dihydro-10,11-dihydroxycarbamazepine were found to be the most abundant., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A fast and easy tailored dispersive solid-phase extraction (d-SPE) procedure has been developed for the determination of 13 cytostatic drugs. Combined with a rapid and simultaneous ultra performance liquid chromatography/tandem mass spectrometry method for residue identification and quantification in urine, it has been fully validated and tested to study a realistic situation in working environment. The target compounds were chosen from the most common classes used in hospitals. The d-SPE adsorbent was obtained mixing Oasis HLB® with C18 and applied to a large volume of sample (10 mL). The electrospray ionization-mass spectrometry acquisition was conducted in a mixed period mode: six acquisition windows were in positive ionization and one in negative (for 5-fluorouracil). The lowest limit of quantification was found at 0.04 μg/L urine for methotrexate. The absolute recovery of cytotoxic drugs was assessed at two concentrations levels and ranged from 67.1% (cytarabine) to 102.3% (etoposide) and from 65.3% (cytarabine) to 101.2% (methotrexate) for the lower and higher levels, respectively, with the relative standard deviation always <12%. This method gives the opportunity to analyze drugs in a wide molecular weight range (from 130 to 853 a.m.u.) and in a complex matrix, such as urine, without losing any of the features that a method intended for trace quantification must have. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

A sensitive and selective ultra-performance liquid chromatography-tandem mass spectrometry method has been developed and validated for the simultaneous analysis of selected tyrosine kinase inhibitors (TKIs)(gefitinib GEF, erlotinib ERL), corticosteroids (dexamethasone DEX, prednisolone PRED), and the antiemetic ondansetron (OND) in rat plasma samples. After the addition of domperidone (DOM) as internal standard (IS), spiked plasma samples were prepared using the solid phase extraction (SPE) C 18 cartridges. Chromatographic separation was performed on a Waters BEH C18 column with an isocratic elution using a mobile phase composed of acetonitrile and water, each with 0.1% formic acid, (80: 20, v/v), at a flow rate of 0.2 mL/min. Quantitation of the analytes was performed using the multiple reaction monitoring (MRM) mode with the positive ionization mode at m/z 447.25>128.08 (GEF), m/z 394.20>278.04 (ERL), m/z 393.30>147.04 (DEX), m/z 361.29>147.02 (PRED), m/z 294.18>170.16 (OND), and m/z 426.26>175.07 (DOM). The method was validated over the concentration range of 0.025-100 (GEF, ERL, OND) and 0.05-100 ng/mL plasma (PRED, DEX) with very low lower limit of quantification of 0.025 (GEF, ERL, OND) and 0.05 ng/mL (DEX, PRED). The intra- and inter-day precision (RSD%) evaluated at four different concentration levels were within the acceptable limits (<15%). The method provided good extraction recovery of all analytes from rat plasma (Er% from -14.05 to -1.08). The validated method was successfully applied to the pharmacokinetic studies following the oral administration of selected combinations of the studied drugs. This study can be readily applied in therapeutic drug monitoring (TDM) in patients receiving these drug combinations as well as investigation of possible drug interactions between TKIs and DEX/PRED/OND., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This research was mainly focused on the effects of food emulsifier on the bioavailability of six priority controlling phthalate acid esters (PAEs) for the further accurate assessment of their toxic effects, using the corresponding phthalate acid monoesters (PAMEs) in rats urine as biomarkers. Glycerin monostearate was chosen as typical food emulsifier. A method was established to determine PAMEs in urine from rats either in experimental group (integrated gavaged with glycerin monostearate and PAEs) or in control group (gavaged with PAEs only), by using solid-phase extraction (SPE) coupled with ultra performance liquid chromatography tandem mass spectrometry (SPE-UPLC-MS/MS). Extraction recoveries were more than 75% for all the PAMEs; the calibration curve was linear in the range of 1.0-1000.0ng/mL with R(2)>0.995; the limits of detection (LOD) were 0.30ng/mL-0.50ng/mL. In addition, by analysing quality control (QC) urine samples in 3 days, it showed that the method was precise and accurate, for the intra-day and inter-day RSD within 16%, and the accuracy more than 82%. Internal exposure amount of all PAEs in experimental group was significantly higher than that in control group with p values of less than 0.05 except for butyl benzyl phthalates (BBP) (P=0.07). The bioavailability of all PAEs ranged from 5.03% to 109.35% with the presence of food emulsifiers glycerin monostearate, observably higher than that without glycerin monostearate (1.12% to 54.39%). It indicated that food emulsifiers increased the bioavailability of PAEs and may lead to potential food safety risk, which should bring awareness and be further studied., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A simple and rapid extraction procedure for the simultaneous determination of eight mycotoxins (Alternaria toxins, ochratoxin A, patulin, citrinin) in a variety of fruit matrices has been developed using ultra high performance liquid chromatography coupled to tandem mass spectrometry. The procedure involves a one-step cleanup using homemade solid phase extraction (SPE) cartridges. By comparative evaluation among six various adsorbents (C18, PSA, HLB, MCX, Silica, NH2), the combination of MCX and NH2 was found to provide the most effective cleanup, removing the greatest number of matrix interferences and also allowing the quantification of all analyzed mycotoxins in fruits. The optimized extraction conditions including acidified aqueous acetonitrile and an additional salt-out step using NaCl were employed before SPE cleanup. Method validation was performed by analyzing samples spiked at three levels (LOQ, 2 LOQ and 10 LOQ). Four fruits including apple, sweet cherry, tomato and orange fruits were selected, and accuracy (recovery%), precision (RSD%), limits of quantification (LOQ), linearity and matrix effect were evaluated during validation. Matrix-matched linearity with correlation coefficients ≥ 0.9921 was established in the range of 5-200 ng mL(-1) for patulin and 1-200 ng mL(-1) for other mycotoxins, respectively. Recoveries between 74.2% and 102.4% and relative standard deviations lower than 4.7% were obtained for all tested fruits. The matrix effect observed was low (≤ ± 17%) in all three fruit matrixes with the exception of orange, for which strong ion suppression was observed for alternariol (25.3%), ochratoxin A (31.6%) and citrinin (40.3%). Therefore, matrix-matched calibration was used for a correct quantification in order to compensate for matrix effect. The limits of quantification (LOQ), ranging from 1 to 5 μg kg(-1) depending on mycotoxins type, were always lower than maximum permitted levels for every regulated mycotoxin by the current European legislation., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A rapid, sensitive, accurate and specific ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) method for the detection of N-nitrosodiethanolamine (NDELA), a highly toxic contaminant in cosmetic raw materials and products was developed and validated. Systematized sample preparation steps were developed according to product types. Various SPE cartridges and columns were examined to establish the condition of SPE and chromatographic separation for NDELA. Sample cleanup steps consisting of solvent and liquid-liquid extraction tailored to the various sample matrix types were established prior to mixed mode SPE (Bond Elut AccuCAT). Chromatographic separation was achieved within 7 min on a porous graphitic carbon (PGC) column using a gradient elution with the mobile phase of 1mM ammonium acetate containing 0.1% acetic acid and methanol. NDELA was monitored using an electrospray positive ionization mass spectrometry in the multiple reaction monitoring (MRM) mode (m/z 134.9>103.7(quantifier) and 73.7(qualifier ion)) with d8-NDELA (m/z 143.1>111.0) as internal standard. The standard curves were linear over the concentration range of 1-100 ng/mL with a correlation coefficient higher than 0.99. The limit of detection (LOD) and the limit of quantification (LOQ) was 10 and 20 μg/kg, respectively (0.5 and 1 ng/mL in standard solution). The intra- and inter-day precisions were estimated to be below 11.1% and accuracies were within the range of 90.8-115.8%. The validated method was successfully applied to the analysis of real samples including raw materials, skin care, make-up, shampoos and hair products., (Copyright © 2015 Elsevier B.V. All rights reserved.)

An automated, size-exclusion solid phase extraction (SPE)-UPLC-MS/MS protocol without pre-treatment of samples was developed to screen for four mycotoxins (OTA, ZEN, AFB1, and AFM1) in liquid milk and milk powder. Firstly, a mixed macropore-silica gel cartridge was established as a size-exclusion SPE column. The proposed methodology could be a candidate in green analytical chemistry because it saves on manpower and organic solvent. Permanent post-column infusion of mycotoxin standards was used to quantify matrix effects throughout the chromatographic run. Matrix-matched calibration could effectively compensate for matrix effects, which may be caused by liquid milk or milk powder matrix. Recovery of the four mycotoxins in fortified liquid milk was in the range 89-120% and RSD 2-9%. The LOD for the four mycotoxins in liquid milk and milk powder were 0.05-2 ng L(-1) and 0.25-10 ng kg(-1), respectively. The LOQ for the four mycotoxins in liquid milk and milk powder were 0.1-5 ng L(-1) and 0.5-25 ng kg(-1), respectively., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A novel and advanced technology on solid phase extraction column prior to liquid chromatography coupled to tandem mass spectrometry has been used for the determination of ochratoxin A in red wine samples. Due to the need of a reliable and rugged method according to current regulations and with the aim of minimize heuristic efforts associated with analytical method development, the statistical design of experiment was employed. On other hand, the method validation according to European Commission 2002/657/EC was achieved. The values obtained for decision limit (CCα), detection capability (CCβ), limits of detection and quantification were 0.07 μg L(-1), 0.14 μg L(-1), 0.13 μg L(-1) and 0.41 μg L(-1), respectively. The recoveries values were ranged from 95.7% to 107.2%. These values were compatible with the 2.0 μg L(-1) maximum allowable concentration limit established by different international regulations., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Aquatic organisms from freshwater ecosystems impacted by waste water treatment plant (WWTP) effluents are constantly exposed to constant concentrations of pharmaceuticals, endocrine disruptors and related compounds, among other anthropogenic contaminants. Macroinvertebrates inhabiting freshwater ecosystems might be useful bioindicators of exposure to contaminants, since their lives are long enough to bioaccumulate, but at the same time may integrate short-term changes in the environment. However, studies about potential bioaccumulation of emerging contaminants in these organisms are very scarce. The objectives of this study were to develop an analytical methodology for the analysis of 41 pharmaceuticals and 21 endocrine disruptors in freshwater invertebrates. In addition, bioaccumulation of these contaminants in three macroinvertebrate taxa inhabiting a waste water treatment plant -impacted river was evaluated. The method for the simultaneous extraction of both families of compounds is based on sonication, purification via removal of phospholipids, and analysis by ultra performance liquid chromatography coupled to a mass spectrometer (UPLC-MS/MS) in tandem. Recoveries for pharmaceuticals were 34-125%, and for endocrine disruptors were 48-117%. Method detection limits (MDLs) for EDCs were in the range of 0.080-2.4 ng g(-1), and for pharmaceuticals, 0.060-4.3 ng g(-1). These pollutants were detected in water samples taken downstream the waste water treatment plant effluent at concentrations up to 572 ng L(-1). Two non-esteroidal anti-inflammatory drugs, diclofenac and ibuprofen, and four endocrine disruptors - estrone, bisphenol A, TBEP, and nonylphenol - were detected in at least one macroinvertebrate taxa in concentrations up to 183 ng g(-1) (dry weight). An isobaric interference was identified during the analysis of diclofenac in Hydropsyche samples, which was successfully discriminated via accurate mass determination by TFC-LTQ Orbitrap., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Paclitaxel is a good compound for regional (intraperitoneal) chemotherapy of peritoneal carcinomatosis. During IPEC, a cytotoxic solution is circulated in the peritoneal cavity, thereby promoting close contact between the cytotoxic agent and the exposed (residual) tumour tissue. To further explore the role of PTX in this type of treatment and study the impact of treatment modalities on tumour tissue penetration, in-vivo animal experiments were set-up. In literature, PTX tumour uptake is frequently studied using autoradiography and/or fluorescence microscopy techniques. Owing to their semi-quantitative nature on one hand and the difficulty of incorporating imaging data within a pharmacokinetic-pharmacodynamic modelling framework on the other hand, we set out to develop a validated assay for the quantification of PTX in tumour tissue samples. Furthermore, in order to maximise spatial resolution, care was taken to minimise the sample weight necessary for the analysis. Based on an enzymatic tumour tissue digestion protocol, an easy, less labour-intensive, when compared to mechanical tissue disruption techniques, method was developed. Through validation experiments we showed that our method reliably quantifies PTX in a working range of 30-8000 ng/g tumour tissue. Finally, using samples from the in-vivo experiments we demonstrated the suitability of the developed method., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this paper, graphene, a new sorbent material, was synthesized and used for solid-phase extraction (SPE) of the six carbamate pesticides (pirimicarb, baygon, carbaryl, isoprocarb, baycarb and diethofencarb) in environmental water samples. The target analytes can be extracted on the graphene-packed SPE cartridge, and then eluted with acetone. The eluate was collected and dried by high purity nitrogen gas at room temperature. 1mL of 20% (v/v) acetonitrile aqueous solution was used to redissolve the residue. The final sample solution was analyzed by ultra performance liquid chromatography-tandem quadrupole mass spectrometry (UPLC-MS/MS) system. Under optimum conditions, good linearity was obtained for the carbamates with correlation coefficient in the range of 0.9992-0.9998. The limits of detection (S/N=3) for the six carbamate pesticides were in the range of 0.5-6.9ngL(-1). Relative standard deviations (RSD) for five replicate determinations were below 5.54%. RSD values for cartridge-to-cartridge precision (n=7) were in the range of 1.27-8.13%. After proper regeneration, the graphene-packed SPE cartridge could be re-used over 100 times for standard solution without significant loss of performance. The enrichment factors for the target analytes were in the range of 34.2-51.7. The established method has been successfully applied to the determination of carbamate pesticide residues in environmental water samples such as river water, well water and lake water., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A rapid method was developed for determination of endogenous cytokinins (CKs) based on magnetic solid-phase extraction (MSPE) followed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). We illustrated the hydrophilic character of bare Fe3O4 nanoparticles that were directly used as a MSPE sorbent for rapid enrichment of endogenous CKs from complex plant extract. To the best of our knowledge, this is the first report of bare Fe3O4 directly used as efficient extraction sorbent to enrich target CKs based on hydrophilic interaction. Under the optimized conditions, a rapid, sensitive and high-throughput method for the determination of 16 CKs was established by combination of MSPE with UPLC-MS/MS. Good linearity was obtained with correlation coefficients (r) from 0.9902 to 0.9998. The limits of detection (LODs) and quantification (LOQs) ranged from 1.2 pg mL(-1) to 391.3 pg mL(-1) and 4.1 pg mL(-1) to 1304.3 pg mL(-1), respectively. 16 CKs could be successfully determined in spiked sample with 80.6-117.3% recoveries and the relative standard deviations (RSDs) were less than 16.6%. Finally, 10 endogenous CKs were successfully quantified in 50mg Oryza sativa sample using the developed MSPE-UPLC-MS/MS method., (Copyright © 2014 Elsevier B.V. All rights reserved.)

An UPLC-MS/MS method for determination of ten steroid hormones in animal origin food has been developed with pretreatment of the samples by matrix solid-phase dispersion (MSPD). The MSPD conditions, including the dispersing sorbents, elution solvents, ratio of sorbent to sample and the volume of the elution solvent have been investigated and optimised, and the method has been evaluated and validated. The results showed that the developed method has satisfactory linearity between the MS/MS responses of the analytes and the concentration of the steroid hormones, and the limits of the detection can reach 0.01μg/kg for most of the analytes. The spiking recoveries of the steroid hormones in chicken, pork, beef and sausage samples were between 76.8% and 98.7% with RSDs lower than 10%. The results demonstrated that the developed approach has high sensitivity and repeatability, and can rapidly determinate the trace residues of steroid hormones in complex food matrices., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A rapid and effective method for the simultaneous determination of cyflumetofen and its main metabolite residues in samples of plant and animal origin (tomato, apple, eggplant, soybean, green tea, fish, and pork liver) was developed using ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Samples were extracted with acetonitrile and cleaned-up with multi-walled carbon nanotubes (MWCNTs). The determination of the presence of target compounds was achieved in less than 4.0min using an electrospray ionization source in the positive mode (ESI+) for cyflumetofen and 2-(trifluoromethyl) benzamide (B-3) and the negative mode (ESI-) for α,α,α-trifluoro-o-toluic acid (B-1). The entire method was validated by evaluating the repeatability, linearity, precision, trueness, and matrix effect. Average recoveries of the analytes were in the range of 79.3-117.6% with relative standard deviation values below 7.6%. Limits of quantification (LOQs) ranged from 0.7 to 9.8μgkg(-1), which were lower than the maximum residue limits (MRLs) for the cyflumetofen found in foods in Japan., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Huperzine A is a reversible and selective cholinesterase inhibitor and has been approved for the treatment of Alzheimer's diseases. In this study, we developed a highly sensitive and specific ulta‐high‐performance liquid chromatography–tandem mass spectrometry method for the determination of Huperzine A in rat plasma. An aliquot of 50 μL of rat plasma sample was pretreated with 200 μL of acetonitrile‐methanol (v/v; 1:1) containing 0.2% formic acid followed by solid phase extraction. The resulting sample was separated on a Waters ACQUITY BEH C18 column using acetonitrile and water containing 0.2% formic acid as mobile phase, at a flow rate of 0.3 mL/min. Multiple‐reaction monitoring (MRM) mode was used for quantitative analysis of Huperzine A in positive electrospray ionization. In the concentration range of 0.01–10 ng/mL, Huperzine A showed excellent linearity with correlation coefficient > 0.998. The intra‐ and inter‐day RSD% were less than 9.7%, while the RE% ranged from −6.7% to 10.0%. The mean recovery was >84.5%. The validated method was demonstrated to be selective, sensitive, and reliable, which has been successfully applied to pharmacokinetic study of Huperzine A in rat plasma. Huperzine A displayed a long half‐life in rat plasma and high oral bioavailability. [ABSTRACT FROM AUTHOR]

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

Highlights: What are the main findings? The validated method was robust, reliable, and sensitive for quantifying ABZ, ABZ-OX, ABZ-ON, and PR simultaneously from the plasma and dried blood spots. The method is well suited for therapeutic drug monitoring due to its high sensitivity, minimal sample volume requirement, and the ability for remote collection. What is the implication of the main finding? Dried blood spot (DBS) analysis represents an alternative sampling technique over conventional blood-sampling methods, particularly for sample collection, enabling a non-clinical setup without requiring special equipment or trained healthcare personnel. Additionally, it minimizes the solvent volume and analysis time and reduces transportation and storage needs. Millions of individuals throughout the world suffer from lymphatic filariasis (LF), which is a morbid disease caused by Wuchereria bancrofti, Brugia malayi, and Brugia timori. These infections belong to tissue-invading nematodes and are one of the major neglected tropical diseases that often result in permanent and enduring disability among individuals in endemic regions. Due to combination therapy, LF eradication has drastically decreased infections globally. The development of blood micro-sampling techniques allowing precise quantitation of drugs in blood would facilitate pharmacokinetic (PK) studies in remote populations. Therefore, an LC-MS/MS bioanalytical method was utilized to analyze albendazole (ABZ), albendazole sulfone (ABZ-ON), albendazole sulfoxide (ABZ-OX), and probenecid (PR) in plasma and dried blood spots. Solid-phase extraction was utilized to extract the analyte from both plasma and blood-spiked DBS. Analytes of interest were eluted with a gradient mobile system using 0.05% formic acid in water (A) and 0.05% formic acid in methanol (B) and separated using a reversed-phase Acquity ®BEH C18 UPLC column (100 × 2.1 mm, 1.7 µm). Precision and accuracy at each QC level were within the acceptable limit, i.e., ±15% for all analytes in both the matrices. Tests for stability under laboratory and storage conditions indicated that no notable changes were observed for plasma and DBS. The LC-MS/MS method demonstrated its capability to consistently identify all target analytes (ABZ, ABZ-ON, ABZ-OX, and PR) at low concentrations, even at the small specimen volumes obtained from DBS cards. This confirms the efficacy and durability of DBS cards as a micro-sampling technique. Moreover, it enhances collection efforts for therapeutic drug monitoring in remote locations for patients infected with lymphatic filariasis. [ABSTRACT FROM AUTHOR]

A total of 769 wheat kernels collected from six provinces in China were analyzed for beauvericin (BEA) and four enniatins (ENNs), namely, ENA, ENA1, ENB and ENB1, using a solid phase extraction (SPE) technique with ultra-high performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). The results show that the predominant toxin was BEA, which had a maximum of 387.67 μg/kg and an average of 37.69 μg/kg. With regard to ENNs, the prevalence and average concentrations of ENB and ENB1 were higher than those of ENA and ENA1. The geographical distribution of BEA and ENNs varied. Hubei and Shandong exhibited the highest and lowest positive rates of BEA and ENNs (13.46% and 87.5%, respectively). However, no significant difference was observed among these six provinces. There was a co-occurrence of BEA and ENNs, and 42.26% of samples were simultaneously detected with two or more toxins. Moreover, a significant linear correlation in concentrations was observed between the four ENN analogs (r range: 0.75~0.96, p < 0.05). This survey reveals that the contamination and co-contamination of BEA and ENNs in Chinese wheat kernels were very common. [ABSTRACT FROM AUTHOR]

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

A novel co-bonded octyl and pyridine silica (OPS) sorbent was prepared and applied for the solid phase extraction (SPE) of cyclopiazonic acid (CPA, a type of mycotoxin) in feed and agricultural products for the first time. A simple mixed-ligand one-pot reaction strategy was employed for OPS sorbent preparation. Nitrogen adsorption–desorption measurements, elemental analysis (EI), thermal gravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT-IR) analysis demonstrated the successful immobilization of octyl and quaternary ammonium groups onto the surface of silica gel. The large specific surface area, high-density functional groups, and mixed-mode anion-exchange characteristics of these silica particles made them the ideal material for the efficient extraction of CPA. Additionally, the OPS sorbents displayed excellent batch-to-batch reproducibility, satisfactory reusability, and low cost. The SPE parameters were optimized to explore the ionic and hydrophobic interactions between CPA and the functional groups, and the ultra-high performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-MS/MS) parameters were optimized to obtain a desirable extraction efficiency and high sensitivity to CPA. Meanwhile, the OPS sorbent presented a satisfactory extraction selectivity and low matrix effect. Under the optimized conditions, our developed CPA detection method was used to determine CPA level in rice, wheat flour, corn flour, peanut, and feed samples, exhibiting a lower detection limit, better linearity, higher sensitivity, and satisfactory extraction recovery rate than previously reported methods. Therefore, our method can be preferentially used as a method for the detection of CPA in agricultural products and feeds. [ABSTRACT FROM AUTHOR]

A method employing online solid phase extraction (SPE) coupled to UPLC-MS/MS was developed for the determination of residues of the acid herbicide quinclorac plus its transformation product, quinclorac methyl ester, in honey. The analytical method involved dissolving the honey in a mixture of methanol:water followed by direct injection into a two-dimensional UPLC system which is used to perform an automated SPE cleanup on a reusable phenyl cartridge prior to the target analytes being transferred onto an analytical UPLC column for subsequent chromatographic separation followed by MS/MS detection. The limits of quantitation for quinclorac and quinclorac methyl ester in honey were both set at 0.5 µg kg−1 and the method detection limit was estimated to be 0.012 µg kg−1 for each compound. The working analytical range (0.5–100 µg kg−1) was validated by analysing a series of spiked replicate honey samples. The method was applied to the analysis of various honeys obtained from numerous different commercial sources. Quinclorac was detected in 9 out of 30 samples at concentrations ranging from 0.6 to 31.5 µg kg−1. Quinclorac methyl ester, which is estimated to be significantly more toxic than the parent herbicide itself, was not detected in any honey sample. [ABSTRACT FROM AUTHOR]

Our previously reported, first validated, UPLC-MS/MS-based simultaneous analysis of five human milk B-vitamins revealed severe matrix effects. High levels of endogenous lactose fouled the electrospray ionization source affecting the analysis. We evaluated solid-phase extraction (SPE), liquid-solid extraction (LSE), protein precipitation (PPT), and liquid chromatography effluent diversion for lactose-removal. SPE failed to separate lactose from vitamins; LSE using 2-propanol reduced lactose and vitamin recoveries. PPT-solvent, milk volume, and reconstitution solvent influenced flavin adenine dinucleotide, pyridoxal and nicotinamide recoveries. Using an optimized LC-gradient enabled chromatographic separation of lactose from vitamins and its removal using a post-column switch-valve. Only 40 µL milk was subjected to methanol-PPT and non-polar matrix removal by methyl tert-butyl ether. B-vitamin recoveries were established (81.9-118.6%; CV ≤ 11.9%; precision: 4.9-13.7%) with greatly reduced matrix effects, and improved process efficiency, and recovery.

Despite potential health implications, data on the presence of Glyphosate (GLY) and other non-GLY herbicides in human matrices remain scarce. This study aimed to develop a simple and cost-effective methodology for detecting and quantifying GLY, its primary biodegradation product; aminomethylphosphonic acid (AMPA); and glufosinate (GLU) in plasma and urine of environmentally and occupationally exposed populations from the province of Córdoba (Argentina). Different alternatives of pre-treatment, derivatization with FMOC-Cl, solid phase extraction, and final sample conditioning steps were evaluated to improve the quantification of the herbicides by a high-performance liquid chromatography system coupled to a triple-quadrupole mass spectrometer. Recoveries ranged from 39 to 84% in both matrices, while limits of quantification were 3, 1, and 0.3 ng/mL and 3.6, 5.1, and 0.3 ng/mL for AMPA, GLY, and GLU in plasma and urine, respectively. In plasma samples, GLY was the most frequently detected analyte (32%), followed by GLU (10%). In urine samples, GLU was the most frequently detected herbicide (13%), followed by GLY (6%). No differences between group or matrix correlations were found. This study is the first report of GLU in human biological matrices and should be used to establish baseline values for future surveillance systems. [ABSTRACT FROM AUTHOR]

Existing methods for the analysis of pesticides in human breast milk involve multiple extraction steps requiring large sample and solvent volumes, which can be a major obstacle in large epidemiologic studies. Here, we developed a simple, low-volume method for extracting organophosphates, pyrethroids, carbamates, atrazine, and imidacloprid from 100 to 200 μL of human breast milk. Multiple extraction protocols were tested including microwave-assisted acid/base digestion and double-solvent extraction with 2 or 20 mL of 2:1 (v/v) dichloromethane/hexane, with or without subsequent solid-phase extraction (SPE) cleanup. Samples were analyzed by liquid chromatography tandem mass spectrometry. Analyte recoveries and reproducibility were highest when 100-200 μL of milk were extracted with 2 mL of dichloromethane/hexane without subsequent SPE steps. Analysis of 79 breast milk samples using this method revealed the presence of carbamates, organophosphates, pyrethroids, and imidacloprid at detection frequencies of 79-96, 53-90, 1-7, and 61%, respectively. This study demonstrates the feasibility of a simple low-volume extraction method for measuring pesticides in human breast milk.

In order to further grasp the contamination level of Alternaria toxins in red date, this study took commercially available red date and its products as the research objects, explored the extraction method of mycotoxins with QuChERS as the core and established ultra-high performance liquid chromatography-tandem mass spectrometry analysis technology for five kinds of Alternaria toxins in red dates, and analyzed the pollution level of Alternaria toxin in red jujube and its products. Results showed that the recovery of Alternaria toxins in solid samples by QuChERS method ranged from 74.89% to 98.04%, and in liquid samples by solid-phase extraction method ranged from 68.35% to 99.63% with the relative standard deviations less than 10%. After the determination of five Alternaria toxins in Jun-date from Aksu, Kashi and Hotan regions, two toxins, TeA and AOH, were detected. Among them, the TeA in Jun-date in Kashgar was the highest, reaching 5.12~10.76 μg/kg. Three Alternaria toxins, TeA, AOH and ALT, were detected in 11 kinds of products of red date, among which TeA in red date wine reached 127.08 μg/kg and AOH was detected only in amethyst date, with content ranging from 34.76 to 98.61 μg/kg. ALT was detected in freeze-dried red dates slices, fried red dates and amethyst date, with content ranging from 2.04 to 399.64 μg/kg. In this paper, a UPLC-MS/MS method was developed to meet the requirements for the determination of Alternaria toxins in date samples with different forms, it would provide a theoretical basis for the edible safety of red dates.

In hepatocellular carcinoma treatment, sorafenib, oxaliplatin, 5-fluorouracil, capecitabine, lenvatinib, and donafenib are first-line drugs; regorafenib, apatinib, and cabozantinib are second-line drugs; and oxycodone, morphine, and fentanyl are commonly used analgesics. However, the high degree of interand intra-individual variability in the efficacy and toxicity of these drugs remains an urgent issue. Therapeutic drug monitoring (TDM) is the most reliable technical means for evaluating drug safety and efficacy. Therefore, we developed an ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneous TDM of three chemotherapy drugs (5-fluorouracil, oxaliplatin, and capecitabin), six targeted drugs (sorafenib, donafenib, apatinib, cabozantinib, regorafenib, and lenvatinib), and three analgesics (morphine, fentanyl, and oxycodone). We extracted 12 analytes and isotope internal standards (ISs) from plasma samples by magnetic solid phase extraction (mSPE) and separated them using a ZORBAX Eclipse Plus C18 column with water containing 0.1% formic acid and methanol containing 0.1% formic acid as the mobile phase. The analytical performance of our method in terms of sensitivity, linearity, specificity, carryover, precision, limit of quantification, matrix effect, accuracy, dilution integrity, extraction recovery, stability, and crosstalk of all the analytes under different conditions met all the criteria stipulated by the guidelines of the Chinese Pharmacopoeia and U.S. Food and Drug Administration. The response function was estimated at 10.0-10 000.0 ng/mL for sorafenib, donafenib, apatinib, cabozantinib, regorafenib, and lenvatinib, and 20.0-20 000.0 ng/mL for 5-fluorouracil, oxaliplatin, capecitabin, morphine, fentanyl, and oxycodone, with a correlation of > 0.9956 for all compounds. The precision and accuracy of all analytes were < 7.21% and 5.62%, respectively. Our study provides empirical support for a simple, reliable, specific, and suitable technique for clinical TDM and pharmacokinetics. [ABSTRACT FROM AUTHOR]

A new, simple and sensitive method for determining and confirming methylene blue and its analogues such as azure A, azure B, azure C, thionine, and new methylene blue in fish muscles have been developed. The method is based on acetonitrile extraction followed by extract purification using dispersive solid-phase extraction (dSPE) with basic aluminium oxide (ALN) and solid-phase extraction (SPE) using primary and secondary amines (PSA) sorbent in matrix adsorption mode. The separation and detection of the dyes in the fish extract are achieved within 5 min by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) using an octadecyl analytical column with a mixture of acetonitrile, methanol and 0.1% formic acid as a mobile phase in gradient elution. The developed method has been in-house validated according to European law. The method recovery for fish muscle was 98.3–103.1%, whereas the decision limit (CCα) was from 0.45 to 0.49 µg kg−1. [ABSTRACT FROM AUTHOR]

Antibiotics are among the most common medicine groups since they are used to treat infectious diseases, as nutritional supplements in livestock breeding, and for preservation in the food industry. Turkey is among the highest antibiotic consumers in the world. In the present study, the most popular 14 antibiotics available in Turkey were monitored in one hospital sewage and two urban wastewater treatment plant influents and effluents seasonally in Istanbul province, the largest metropolitan center in Turkey. The present research aimed to develop a robust analytical method to determine 14 antibiotics, including six chemical groups, in environmental matrices which are considered significant antibiotic pollution sources, namely hospital sewage and urban wastewater. Solid-phase extraction (SPE) and UPLC-MS/MS analysis parameters included optimized column temperature, eluent, mobile phase, and flow rate. Three SPE cartridges were employed in recovery studies. The antibiotic recovery rates varied between 40 and 100%, and all analytes were identified within 3 min with UPLC-MS/MS under optimal conditions. It was determined that method detection limits (MDLs) varied between 0.07 and 2.72 µg/L for the antibiotics. In all seasons, the highest beta-lactam group antibiotic concentrations were identified in hospital sewage. The season with the greatest variety of antibiotics in urban wastewater was spring. Clarithromycin and ciprofloxacin were the antibiotics determined at the highest concentration in the influent and effluent of the wastewater treatment plant in all seasons. This study showed that the most widely used beta-lactam group antibiotics were found in high amounts in hospital sewage wastewater but in low concentrations in the treatment plants, and hence, it is seen that the degradability of beta-lactam group antibiotics was high. The presence of clarithromycin, ciprofloxacin, lincomycin, levofloxacin, and trimethoprim antibiotics in hospital sewage in higher amounts and also in inlet and outlet of wastewater treatment plants proves that those are resistant antibiotics. [ABSTRACT FROM AUTHOR]

Alkylphenol ethoxylates (APEOs) represent a non-ionic surfactant widely used as adjuvants in pesticide formulation, which is considered to cause an endocrine-disrupting effect. In the current study, we established a detection method for the APEOs residue in tea based on solid-phase extraction (SPE) for the simultaneous analysis of nonylphenol ethoxylates (NPEOs) and octylphenol ethoxylates (OPEOs) by UPLC–MS/MS. In the spiked concentrations from 0.024 to 125.38 μg/kg for 36 monomers of APEOs (nEO = 3–20), the recoveries of APEOs range from 70.3–110.7% with RSD ≤ 16.9%, except for OPEO20 (61.8%) and NPEO20 (62.9%). The LOQs of OPEOs and NPEOs are 0.024–6.27 and 0.16–5.01 μg/kg, respectively. OPEOs and NPEOs are detected in 50 marketed tea samples with a total concentration of 0.057–12.94 and 0.30–215.89 µg/kg, respectively. The detection rate and the range of the monomers of NPEOs are generally higher than those of OPEOs. The current study provides a theoretical basis for the rational use of APEOs as adjuvants in commercial pesticide production. [ABSTRACT FROM AUTHOR]

In this work, we proposed an acid hydrolysis-based analytical method for the detection of Alternaria toxins (ATs) in solanaceous vegetables and their products with solid-phase extraction (SPE) and ultrahigh-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS). This study was the first to reveal that some compounds in the eggplant matrix bind to altenusin (ALS). Validation under optimal sample preparation conditions showed that the method met the EU criteria, exhibiting good linearity (R2 > 0.99), matrix effects (−66.6–−20.5%), satisfying recovery (72.0–107.4%), acceptable precision (1.5–15.5%), and satisfactory sensitivity (0.05–2 µg/kg for limit of detection, 2–5 µg/kg for limit of quantification). Out of 393 marketed samples, only 47 samples were detected, ranging from 0.54–806 μg/kg. Though the occurrence ratio (2.72%) in solanaceous vegetables could be negligible, the pollution status in solanaceous vegetable products was much more serious, and the incidences were 41.1%. In the 47 contaminated samples, the incidences were 4.26% for alternariol monomethyl ether (AME), 6.38% for alternariol (AOH) and altenuene (ALT), 42.6% for tentoxin (TEN), and 55.3% for tenuazonic acid (TeA). [ABSTRACT FROM AUTHOR]

A method for simultaneous determination of 79 pesticides residues in fresh tea leaves by ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS/MS) was establish in this study. The fresh tea leaves were ground by high-speed wall breaking and then extracted by acetonitrile solution with NaCl. The liquid supernatant was centrifuged and purified by solid phase extraction of anhydrous magnesium sulfate, C18, PSA and GCB. The scheduled multiple reaction monitoring mode (sMRM) was used for scanning and determination, and quantitative by external standard method. The results show that the 79 target compounds exhibited good linearity within the concentration range of 0.001~0.400 mg⋅L-1 with a correlation coefficient (R²) of 0.990 6 to 0.999 9. The average recoveries at 5 spiked levels (0.01, 0.03, 0.05, 0.10, 0.20 mg⋅kg-1) ranged from 70.7% to 119.0%, with the relative standard deviations (RSDs) ranging from 0.1% to 19.8%, and the limits of quantitation (LOQ) for the 79 pesticides ranging from 0.01 mg⋅kg-1 to 0.05 mg⋅kg-1. The proposed method is high sensitivity, good accuracy and quick, which is suitable for determination of 79 pesticides residues in fresh tea leaves. [ABSTRACT FROM AUTHOR]

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Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus, However, rarely studies focus on the rapid determination of these residues. Here, a total of 30 kinds of prohibited pesticide residues were determined by ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-MS/MS) in five different process ways. Pretreatment methods, chromatographic separation and detection conditions in mass spectrometry were all optimized accordingly. Among the five different pretreatment methods, the first and third solid phase extraction failed to provide high recoveries of sulfosulfuron compounds (both lower than 60%). Recovery of chlorphenamidine by the Quick Easy Cheap Effective Rugged and Safe multiresidue method (QuEChERS) was lower than 60%, which did not meet the requirements of trace determination. The concentrations of 30 prohibited pesticides residues treated by straightforward and solid phase extraction showed good linearity in their corresponding ranges, with correlation coefficients over 0.99. The average recoveries of straightforward ranged from 78.13% to 110.9%, while RSD ranged from 1.3% to 16.9%, albeit poor purification was observed. The recovery yield from solid phase extraction was between 67.75% and 103.08% with RSD value from 0.8% to 14.0%, which met the requirements of trace determination, this method has good precision and stability. These results could be employed to other Traditional Chinese Medicines (TCMs) in detecting prohibited pesticide residues. [ABSTRACT FROM AUTHOR]

Amino acids (AAs) are important nitrogen-containing organics in water, and a large number of reports have proven that they were the precursors of many nitrogen-containing disinfection by-products, some of which have cytotoxicity and carcinogenicity. However, little has been done on their occurrence in drinking source water. Therefore, a trace determination method via solid-phase extraction coupled with ultra-high pressure liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for 15 free AAs (FAAs) was developed, which was successfully applied for drinking source water samples. For sample preparation, strong cation-exchange stationary solid-phase extraction (SPE) cartridge showed better extraction performance to that of reverse phase stationary oasis HLB SPE cartridge. The optimal water pH was determined to be 2.8 before extraction. Strong matrix effects for most FAAs were observed in this work; thus, sample extraction with SPE was recommended to eliminate the matrix effects. The developed method showed excellent linearity (R2 > 0.991), low limits of detection (LODs, 0.01–0.27 nmol/L), and good recoveries of 69.8–117.9% in drinking source water with low relative standard deviations (RSDs, 0.3–13.2%). The developed method was finally applied to eight drinking source water samples, and the top five FAAs were found to be serine, glycine, leucine, alanine, and isoleucine. [ABSTRACT FROM AUTHOR]