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Background Per- and polyfluoroalkyl substances (PFAS) are a class of persistent organic pollutants that possess potential toxicity to the human body. The production and utilization of diverse emerging PFAS have resulted in widespread human exposure. Therefore, it is imperative to establish a quantitative methodology encompassing a wide range of PFAS for a comprehensive assessment of human exposure to these compounds. Objective To establish a high-throughput quantitative method for the simultaneous determination of 53 PFAS in human serum based on ultra-high-performance liquid chromatography-Q Exactive high resolution mass spectrometry (UPLC-Q Exactive HRMS). Methods The extraction recoveries of hydrophilic-lipophilic balance (HLB) column, weak anionexchange (WAX) column, and 96-well WAX μElution plate were compared to select the SPE column with the highest recovery. The retention time and peak shape of the target compounds were compared between ACQUITY UPLC BEH C18 column and Accucore aQ column, and the more cost-effective column was chosen. The effects of adding different levels of ammonium formate (0, 2, 5 and 10 mmol·L−1) in mobile phase on peak shape and target response were compared to determine the optimal buffer salt concentration. The optimal spray voltage was obtained by comparing −2 kV and −4 kV. The proposed method was validated from the aspects of selectivity, standard curve, limits of detection, precision, accuracy, and matrix effect. The method was applied to 142 umbilical serum samples. Results The best recovery rate (64%-118%) was achieved by using 96-well WAX μElution plate. The optimal separation and peak shape were obtained by utilizing Accucore aQ column with H2O-methanol (containing 5 mmol·L−1 ammonium formate) as the mobile phase. Less in-source collision and better target response were observed when the spray voltage was set to −2 kV. All target analytes had a good linearity, with R2 > 0.99. The limits of detection ranged from 0.01 to 0.50 μg·L−1, and the recovery ranged from 69% to 127% with the precision less than 26%. A total of 31 PFAS were detected in the 142 actual samples, among which 14 PFAS had a detection frequency over 50%. Perfluorooctanoic acid showed the highest median concentration of 4.16 μg·L−1, followed by 6:2 chlorinated polyfluorinated ether sulfonate and perfluorooctane sulfonates (3.50 μg·L−1 and 1.59 μg·L−1, respectively). Conclusion In this study, we establish a UPLC-Q Excative HRMS method for simutanious determination of 53 PFAS concentrations in serum. This method has the advantages of wide coverage of PFAS, good selectivity, and easy operation, and is suitable for biological detection with a large sample size.
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A liquid chromatography-tandem mass spectrometry(LC-MS/MS)method was developed for determination of three kinds of β-agonists(Clenbuterol(CL),Ractopamine(RAC)and Salbutamol(SAL))residues in animal liver samples.The liver sample homogenates were extracted with organic solvent,followed by clean-up using the automatic magnetic solid-phase extraction(MSPE),and then analyzed using LC-MS/MS.The results showed that the magnetic mixed-mode cation exchange adsorbent(M-MCX)exhibited 34%higher adsorption capacity than the conventional mixed-mode cation exchange(MCX)column.Furthermore,the clean-up was conducted by using an automatic MSPE device,and 8 samples could be simultaneously treated within 30 min.The limits of detection(LOD)were 0.01-0.1 μg/kg,the average recoveries ranged from 88.2%to 110.5%,and the relative standard deviations(RSDs)were in range of 2.9%-10.3%at three spiked levels for the three kinds of β-agonists.Compared with the traditional SPE technique,the present method had many advantages such as simple operation,rapidity and high efficiency,which was suitable for high-throughput and automatic detection of residues in routine analysis.
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A new method for simultaneous determination of 23 kinds of per-and polyfluoroalkyl substances(PFASs)(13 kinds of perfluoro carboxylic acids,4 kinds of perfluoro sulfonic acids,and 6 kinds of new substitutes)in plant leaf tissue by ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)using automatic online solid phase extraction(SPE)to remove the matrix interference components in plant crude extracts was developed.The plant leaf samples were extracted twice with 1%formic acid-methanol solution,then evaporated to dry,redissolved with 70%methanol solution,and directly injected for analysis.After 23 kinds of target PFASs were purified automatically by online SPE with a WAX column,the six-way valve was switched to rinse PFASs onto an alkaline mobile phase system-compatible C18 analytical column.Then,the 23 kinds of target PFASs were separated within 16 min by gradient elution using a binary mobile phase system of methanol/water(Containing 0.4%ammonium hydroxide).Tandem mass spectrometry was performed in multiple reaction monitoring(MRM)mode for online detection of various PFASs,and quantification was carried out by internal standard method.The results of the method validation showed that satisfactory average recoveries of 23 kinds of PFASs in plant leaf samples(64.2%-125.5%),precision(relative standard deviations(RSDs)of 0.7%-12.8%),linearity(R2＞0.990),and sensitivity(the detection limits(S/N=3)were in the range of 0.02-0.50 μg/kg)were achieved.Finally,this method was used to detect PFASs in the marine green tide algae(Enteromorpha prolifera)and several tree leaves,and a total of 6 kinds of PFASs were detected,in which PFBA was the main contaminant.Compared with the reported offline SPE methods,the proposed online SPE technique significantly simplified the sample pretreatment process and provided an automatic,simple,and environment-friendly method for the routine monitoring of legacy and emerging PFASs in plant tissues.
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Objective To establish a rapid screening method for 34 emerging contaminants in surface water by ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry(UHPLC-Q-TOF-MS).Methods The pretreatment conditions of solid phase extraction(SPE)were op-timized by orthogonal experimental design and the surface water samples were concentrated and ex-tracted by Oasis? HLB and Oasis? MCX SPE columns in series.The extracts were separated by Kine-tex? EVO C18 column,with gradient elution of 0.1%formic acid aqueous solution and 0.1%formic acid methanol solution.Q-TOF-MS'fullscan'and'targeted MS/MS'modes were used to detect 34 emerging contaminants and to establish a database with 34 emerging contaminants precursor ion,prod-uct ion and retention times.Results The 34 emerging contaminants exhibited good linearity in the con-centration range respectively and the correlation coefficients(r)were higher than 0.97.The limit of de-tection was 0.2-10 ng/L and the recoveries were 81.2%-119.2%.The intra-day precision was 0.78%-18.70%.The method was applied to analyze multiple surface water samples and 6 emerging contaminants were detected,with a concentration range of 1.93-157.71 ng/L.Conclusion The method is simple and rapid for screening various emerging contaminants at the trace level in surface water.
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Objective To establish a simultaneous detection approach for 34 emerging contaminants(ECs)in tap water by liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).Human health risk assessment was performed according to the detection results from 43 tap water samples.Methods Tap water samples were concentrated and extracted by solid phase extraction,and then blown to near dry by nitrogen at 40℃.The sample extracts were dissolved in methanol-water solution(95:5,VN)to 0.5 mL for analyzing.Agilent Jet Stream Electrospray Ionization(AJS ESI)and the multiple reaction monitoring(MRM)mode were performed for MS to acquire the data of 34 ECs.A database including precursor ion,product ion and retention times was established accordingly.Results The average linear correlation coefficients(r)of 34 kinds of ECs was 0.995 9.The limits of detection were 0.01～0.60 ng/L and the recoveries were between 60.7％and 119.8％.The intra-group precisions were between 0.05％～9.89％and the intra-day precisions were between 0.20％～14.40％for the spiked samples.The method was applied to analyze 43 tap water samples and a total of 15 ECs were detected.According to the results,the detection rate of caffeine was the highest(84％),and the concentration range was ND～74.42 ng/L.Among all the ECs detected,1,2,3-benzotriazole had the highest concentration(ND～361.15 ng/L),where detection rate was 44％.Humans may be exposed to these ECs by drinking the tap water.The human health risk assessments of 12 kinds of ECs were carried out,however,the estimated risk was negligible(risk quotient＜0.01).Conclusion The method is simple,highly sensitive and selective,and could meet the detection needs of ECs at trace level in tap water.There was no human health risk posed for ECs identified in 43 tap water samples analyzed by this method.
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Objective To comprehensively characterize the diterpene alkaloids in Radix Aconiti Kusnezoffii.Methods The diterpene alkaloids were isolated and purified by strong acid cation exchange resin solid phase extraction column(SCX-SPE),and identified by ultra high performance liquid chromatography-Q-Exactive Orbitrap mass spectrometry(UHPLC-Q-Exactive Orbitrap MS).Results A total of 99 diterpene alkaloids were identified from Radix Aconiti Kusnezoffii,including 27 diester diterpene alkaloids(DDA),29 monoester diterpene alkaloids(MDA),40 amide diterpene alkaloids(ADA),2 polyester diterpene alkaloids(PDA)and 1 long-chain ester diterpene alkaloid(LDA).Conclusion The SCX-SPE combined with UHPLC-Q-Exactive Orbitrap MS method,established in this paper,can rapidly identify a large number of diterpene alkaloids in Radix Aconiti Kusnezoffii,which provides scientific proof for the study of pharmacodynamic substance basis and quality control of Radix Aconiti Kusnezoffii.
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Objective To establish a method for rapid screening and quantifying the illegal addition of metolazone in tablet candy by ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS).Methods The component in samples was extracted with acetonitrile,then purified by Captiva EMR-Lipid purification column,detected by UPLC-Q-TOF/MS with Agilent RRHD Eclipse Plus C18 chromatographic column(100 mm×2.1 mm,1.8μm)under Targeted MS/MS mode.Results The linear regression analysis data for the calibration plots showed a good linear relationship over the concentration range of 50-1 000 ng·mL-1 for metolazone(r=0.999 0);the value of detection limit and quantification limit was found to be 1.0 μg.g1 and 2.5 μg·g-1.The average recovery rate was 98.15％(RSD=2.2％,n=18).Conclusion The method had the advantages of simple operation,qualitative and quantitative accuracy.It could be applied to daily inspection.
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Objective To establish a direct extraction ultra-high performance liquid chromatography tandem mass spectrometry method for the determination of bongkrekic acid in corn flour. Methods Bongkrekic acid was directly extracted with 80% methanol from corn flour samples, and the supernatant after vortex and centrifugation was determined after passing through membrane filtration. At the same time, the corn flour samples were extracted by solid phase extraction. The determination results of the two methods were compared. Results The linearity of standard series was good within the range of2-20 μg/L, and the linearity coefficient was＞0.999. The determination result of the positive sample by direct extraction method was 193.40 mg/kg (n=6). Adding the standard to the blank sample at the levels of 2, 6, and 10 μg/L, the calculated recovery rate was 75.82% - 99.33%, and the relative standard deviation was 3.54 % - 8.45%. The detection limit of the method reached 6 μg/kg. After extraction by solid phase extraction, the determination result of the positive sample was 196.84 mg/kg (n=6). The recovery rate was 77.12% -100.83%, with a relative standard deviation of 8.32% - 9.54%. Conclusion Compared with the solid phase extraction, the direct extraction method for the extraction of bongkrekic acid from corn flour has the advantages of rapidity, simplicity, and cost savings.
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Objective@#To develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with cation exchange-based solid phase extraction (SPE) for determination of tetrodotoxin (TTX) in salted pufferfish. @*Methods@#Evenly crushed salted pufferfish samples were subjected to ultrasound-assisted extraction with 0.5% acetic acid/50% methanol/water. The extract was cleaned with cation exchange-based SPE cartridge and eluted with 0.3% hydrochloric acid and 50% acetonitrile/water. The eluent was neutralized with ammonia and separated with a Waters XBridgeTM BEH Amide column (150 mm×3.0 mm, 1.7 μm), and determined using LC-MS/MS in a multiple reaction monitoring mode.@*Results@#The matrix effects of TTX were 85.7%-92.4%, and the matrix suppression effect was under effective control following clean-up procedures using the optimized SPE method. The TTX showed a good linear relationship at the range of 2.0 to 4 000 μg/kg, with a correlation coefficient (r2) of 0.999 2. The limits of detection and quantitation for TTX in sample matrix were 1.0 μg/kg and 2.0 μg/kg, respectively. The mean spiked-recovery rates were 81.2% to 96.5% at spiked amounts of 2.0, 200 μg/kg and 2 200 μg/kg, with relative standard deviations (RSDs) of 4.3% to 7.5%. The intraday accuracy and precision of TTX were 84.4% to 95.6% and 4.9% to 5.8% in quality control samples, and the interday accuracy and precision of TTX were 86.1% to 94.9% and 5.5% to 8.5% in quality control samples. The detection of TTX was 60.5% in 38 market-sold salted pufferfish products using the established LC-MS/MS method.@*Conclusion@#The established LC-MS/MS method is effective for accurate quantitative determination of TTX in salted pufferfish.
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Objective To establish a method for the determination of 10 organophosphorus flame retardants in drinking water by on-line solid phase extraction coupled with high performance liquid chromatography-tandem mass spectrometry (On-line SPE-UPLC-MS/MS). Methods After adding the internal standard, the water sample was filtered by Millipore filtration, and then concentrated and detected by Online SPE-UPLC-MS/MS. Samples were concentrated by C8 SPE column and separated by C18 column with acetonitrile-water-formic acid as the mobile phases gradient elution，and were detected by multiple reaction monitoring (MRM) acquisition under anion mode. Results The 10 organophosphorus flame retardants all displayed good linear relationships within a certain range of concentrations, with the correlation coefficients being more than 0.990. The method detection limits were 0.60-5.50 ng/L, and the spiked recoveries of low, medium and high concentrations were 64%-106% , 83%-104% and 85%-99%, respectively. Conclusion The method is simple, sensitive, rapid, accurate and reliable, so it is applicable for the determination of 10 organophosphorus flame retardants in drinking water.
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Abstract Sunset yellow (SY), allura red (AR) and fast green (FG) are frequently used in commercial food products, although they are considered to be hazardous to public health due to their toxic efficacy and high exposure risk potency. In this study, a new, rapid, and reliable method based on a magnetic solid-phase extraction (MSPE) was developed for the simultaneous determination of SY, AR, and FG. Fe3O4 modified with Elaeagnus angustifolia was used for the first time as an adsorbent (Fe3O4-EA) in MSPE. It was characterized with scanning electron microscopy, Brunauer Emmet Teller surface area analysis and X-ray diffraction. MSPE parameters were optimized in terms of pH, adsorption, and elution time and elution volume. High-performance liquid chromatography was used for dye quantitation. Analytical separation was performed by applying ammonium acetate buffer, acetonitrile, and methanol as the mobile phase to a C18 reverse-phase analytical column. Intraday and inter-day repeatability of the method performed at the concentration of 0.2, 1.0 and 2.0 µg/mL exhibited <8.1% RSD (n=3). The limit of detection values was between 0.05-0.1 µg/mL. The adsorption data of SY, AR and FG on Fe3O4-EA were fitted with the Langmuir model with qmax values of 45.0, 70.4 and 73.0 mg/g, respectively.
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@#Objective - To optimize the extraction and quantification methods for the determination of S phenylmercapturic acid - Methods (SPMA) in urine with performance liquid chromatography mass spectrometry. The urine was hydrolyzed with 50.0% sulfuric acid. The hydrolysate was purified by solid phase extraction column. Purified samples were separated by C18 chromatographic column and detected by tandem mass spectrometry. The isotope labeled SPMA was used as the internal Results - standard. The internal standard curve was used for quantification. The linear range of SPMA was 0.50 50.00 μg/L with the correlation coefficient of 0.999 8. The detection limit and the lower limit of quantification were 0.05 and 0.17 μg/L, - - - - respectively. The recovery rate was 97.0% 102.0%. The within run and between run relative standard deviation were 0.6% 1.0% - and 1.7% 6.5%, respectively. The mass concentration of urinary SPMA in the occupational benzene exposure group was - vs P higher than the non occupational benzene exposure group by this method (median: 2.81 0.28 μg/g creatinine, <0.05). Conclusion Compared to the national standard method, this optimized method of solid phase extraction and internal standard for quantification eliminates the matrix effect. This method is accurate and precise, and is suitable for the determination of SPMA acid in urine.
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OBJECTIVES@#To establish the ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method to detect ethanol metabolites phosphatidylethanol (PEth) in whole blood.@*METHODS@#An appropriate amount of aqueous solution including 1% formic acid was added to 100 μL whole blood, the protein was precipitated with acetone, centrifuged and the supernatant was purified and enriched by using Bond Elut Certify column. The eluent was redissolved with 1/1 isopropanol/acetonitrile (v/v) solution after nitrogen blowing and then tested by UPLC-MS/MS. Selective reaction monitoring scanning was carried out in negative ionization mode, and quantitative analysis was performed by external standard method.@*RESULTS@#PEth showed a linear relationship over the concentration range of 1-160 ng/mL in whole blood (r=0.999 9) with peak area. The detection limit was 0.2 ng/mL, the quantification limit was 1 ng/mL, the recovery rate was 97.43%-103.61%, the accuracy was 0.99%-1.77%, the intra-day precision was 0.4%-2.4%, and the inter-day precision was 1.1%-3.3%, and the matrix effect was 91.00%-99.55%. PEth was not detected in the in vitro blood samples supplemented with ethanol. PEth was detected positive in three drunk driving cases, and the concentration were 195.49, 83.67 and 876.12 ng/mL, respectively.@*CONCLUSIONS@#The established method has high sensitivity and specificity and the analysis results are accurate. It is suitable for the qualitative and quantitative analysis of PEth in whole blood.
Assuntos
2-Propanol , Acetona , Acetonitrilas , Biomarcadores , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Etanol , Glicerofosfolipídeos , Nitrogênio , Espectrometria de Massas em Tandem/métodosRESUMO
An innovative sandwich-structural Fe-based metal-organic framework magnetic material(Fe3O4@SW-MIL-101-NH2)was fabricated using a facile solvothermal method.The characteristic properties of the material were investigated by field emission scanning electron microscopy,transmission electron mi-croscopy(TEM),energy-dispersive X-ray spectroscopy,Fourier transform infrared spectroscopy,X-ray powder diffraction,vibrating sample magnetometry,and Brunauer-Emmett-Teller measurements.Fe3O4@SW-MIL-101-NH2 is associated with advantages,such as robust magnetic properties,high specific surface area,and satisfactory storage stability,as well as good selective recognition ability for chlorogenic acid(CA)and its metabolites via chelation,hydrogen bonding,and π-interaction.The results of the static adsorption experiment indicated that Fe3O4@SW-MIL-101-NH2 possessed a high adsorption capacity toward CA and its isomers,cryptochlorogenic acid(CCA)and neochlorogenic acid(NCA),and the adsorption behaviors were fitted using the Langmuir adsorption isotherm model.Then,a strategy using magnetic solid-phase extraction(MSPE)and ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF MS/MS)was developed and suc-cessfully employed for the selective pre-concentration and rapid identification of CA metabolites in rat plasma,urine,and feces samples.This work presents a prospective strategy for the synthesis of magnetic adsorbents and the high-efficiency pretreatment of CA metabolites.
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@#The waste water-based epidemiology is an important technique to fight against drug abuse by analyzing the concentration of illicit drugs in urban sewage, which can monitor the abuse of drugs.An SPE-UPLC-MS/MS method was developed for the analysis of 12 common drugs and their metabolites involving amphetamine and morphine.It was shown that the best result was achieved when hydrochloric acid/ acetonitrile (5∶95) was added to acidify the sample during the concentration process, guaranteeing the anti-across contamination of the analysis of organic nitrogen basic trace components, and improve the stability, specificity, and accuracy of the method.The optimized method meets the analytical requirements of complex sewage samples, and has been successfully applied to the assessment of urban drug abuse through sewage analysis.
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An analytical method was developed for determination of 7 aminoglycosides antibiotics in bear bile powder by hydrophilic interaction liquid chromatography tandem mass spectrometry. The samples were purified by mix-mode weak cation exchange and reversed-phase SPE. Waters ACQUITY UPLC BEH Amide column (100 mm × 3.0 mm, 1.7 μm) was used with 0.2% formic acid aqueous solution-0.2% formic acid acetonitrile solution as mobile phases by gradient elution. The aminoglycosides were detected by electrospray ionization mass spectrometry in positive mode with multiple reaction monitoring (MRM) mode. Spectinomycin, streptomycin, amikacin, kanamycin, tobramycin, apramycin and neomycin possessed good linear correlation in the respective concentration ranges, with the correlation coefficients more than 0.99. The mean recoveries at 3 spiked levels were in the range of 61.3%～127.3%, and the RSDs were 0.1%～1.9%. The limits of quantification were 0.2～1.0 mg·kg-1. The method had been applied to the analysis of actual samples.
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In this study,a functionalized covalent-organic framework(COF)was first synthesized using porphyrin as the fabrication unit and showed an edge-curled,petal-like and well-ordered structure.The synthesized COF was then introduced to prepare porous organic polymer monolithic materials(POPMs).Two com-posite POPM/COF monolithic materials with rod shapes,referred to as sorbent A and sorbent B,were prepared in stainless steel tubes using different monomers.Sorbents A and B exhibited relatively uniform porous structures and enhanced specific surface areas of 153.14 m2/g and 80.01 m2/g,respectively.The prepared composite monoliths were used as in-tube solid-phase extraction(SPE)sorbents combined with HPLC for the on-line extraction and quantitative analytical systems.Indole alkaloids(from Catharanthus roseus G.Don and Uncaria rhynchophylla(Miq.)Miq.Ex Havil.)contained in mouse plasma were extracted and quantitatively analyzed using the online system.The two composite multifunctional monoliths showed excellent clean-up ability for complex biological matrices,as well as superior selec-tivity for target indole alkaloids.Method validation showed that the RSD values of the repeatability(n=6)were≤3.46％,and the accuracy expressed by the spiked recoveries was in the ranges of 99.38％-100.91％and 96.39％-103.50％for vinca alkaloids and Uncaria alkaloids,respectively.Furthermore,sorbents A and B exhibited strong reusability,with RSD values≤5.32％,which were based on the peak area of the corresponding alkaloids with more than 100 injections.These results indicate that the composite POPM/COF rod-shaped monoliths are promising media as SPE sorbents for extracting trace compounds in complex biological samples.
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A rapid and sensitive method for analyzing trace β-blockers in complex biological samples,which involved magnetic solid-phase extraction(MSPE)coupled with Fourier transform ion cyclotron reso-nance mass spectrometry(FTICR-MS),was developed.Novel nanosilver-functionalized magnetic nano-particles with an interlayer of poly(3,4-dihydroxyphenylalanine)(polyDOPA@Ag-MNPs)were synthesized and used as MSPE adsorbents to extract trace β-blockers from biological samples.After extraction,the analytes loaded on the polyDOPA@Ag-MNPs were desorbed using an organic solvent and analyzed by FTICR-MS.The method was rapid and sensitive,with a total detection procedure of less than 10 min as well as limits of detection and quantification in the ranges of 3.5-6.8 pg/mL and 11.7-22.8 pg/mL,respectively.The accuracy of the method was also desirable,with recoveries ranging from 80.9％to 91.0％following the detection of analytes in human blood samples.All the experimental results demonstrated that the developed MSPE-FTICR-MS method was suitable for the rapid and sensitive analysis of trace β-blockers in complex biological samples.
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In this study,ecofriendly and economic carboxy-terminated plant fibers(PFs)were used as adsorbents for the effective in-syringe solid phase extraction(IS-SPE)of fluoroquinolone(FQ)residues from water.Based on the thermal esterification and etherification reaction of cellulose hydroxy with citric acid(CA)and sodium chloroacetate in aqueous solutions,carboxy groups grafted onto cotton,cattail,and corncob fibers were fabricated.Compared with carboxy-terminated corncob and cotton,CA-modified cattail with more carboxy groups showed excellent adsorption capacity for FQs.The modified cattail fibers were reproducible and reusable with relative standard deviations of 3.2％-4.2％within 10 cycles of adsorption-desorption.A good extraction efficiency of 71.3％-80.9％was achieved after optimizing the extraction condition.Based on carboxylated cattail,IS-SPE coupled with ultra-performance liquid chromatography with a photodiode array detector was conducted to analyze FQs in environmental water samples.High sensitivity with limit of detections of 0.08-0.25 μg/L and good accuracy with recoveries of 83.8％—111.7％were obtained.Overall,the simple and environment-friendly modified waste PFs have potential appli-cations in the effective extraction and detection of FQs in natural waters.
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Objective: A method for the determination of acetochlor and its metabolites in urine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was established. Methods: After cleaned-up by a HLB extraction cartridges, the urine was eluted with 1% acetic acid acetonitrile solution. The target compounds were separated by ACQUITY UPLC®HSS T3 Column (2.1 mm×100 mm×1.8 μm) by using 1% formic acid solution and acetonitrile as mobile phase with gradient elution program, and analyzed in positive electrospray ionization mode by liquid chromatography tandem mass spectrometry. Results: All the target compounds showed good linear relationships in the range of 1-50 μg/L, and the correlation coefficients (r) were higher than 0.997. The recoveries rates at three different spiked levels for all target compounds in blank matrices were 107.6%-129.1%, and the relative standard deviations (RSD) were 1.5%-9.9% (n=6) . The limits of detection and quantitation of the method were 0.04-0.11 μg/L and 0.15-0.42 μg/L, respectively, and target substances were detected in all urine samples from occupational exposure workers to acetochlor. Conclusion: This method is suitable for rapid screening and analysis of acetochlor and metabolites in urine with the advantages of accuracy, rapidity, simplicity, high sensitivity and good specificity.