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1.
Solid-phase extraction (SPE) procedures were developed for rapid cleanup and determination of thiabendazole and carbendazim in orange, apple, and grape juices. Samples were prepared by using an SPE cartridge containing a mixed-mode sorbent with both reversed-phase and strong cation-exchange chemistries. Analysis was by liquid chromatography with photodiode-array UV detection. Orange juice was analyzed by mixed-mode cation-exchange extraction with reversed-phase cleanup; the other juices were analyzed by reversed-phase extraction with cation-exchange cleanup. Recoveries >80% for carbendazim and >90% for thiabendazole. Quantitation limits were 20 microg/L for both analytes. 相似文献
2.
Determination of tetracycline residues in soil by pressurized liquid extraction and liquid chromatography tandem mass spectrometry 总被引:2,自引:0,他引:2
Vicente Andreu Pablo Vazquez-Roig Cristina Blasco Yolanda Picó 《Analytical and bioanalytical chemistry》2009,394(5):1329-1339
An optimized extraction and cleanup method for the analysis of chlortetracycline (CTC), doxycycline (DC), oxytetracycline
(OTC) and tetracycline (TC) in soil is presented. Soil extraction in a pressurized liquid extraction system, followed by extract
clean up using solid-phase extraction (SPE) and tetracycline determination by liquid chromatography tandem mass spectrometry
(LC-MS/MS) provided appropriate efficiency and reproducibility. Different dispersing agents and solvents for soil extraction
and several SPE cartridges for cleanup were compared. The best extraction results were obtained using ethylenediamine tetraacetic
acid-treated sand as dispersing agent, and water at 70 °C. The most effective cleanup was obtained using Strata-XTM sorbent in combination with a strong anion exchange cartridge. Recoveries ranged from 71% to 96% and precision, as indicated
by the relative standard deviations, was within the range of 8–15%. The limits of quantification (LOQs) by using LC-MS/MS,
based on signal-to-noise ratio (S/N) of 10, ranged from 1 μg kg−1 for TC to 5 μg kg−1 for CTC. These results pointed out that this technique is appropriate to determine tetracyclines in soils. Analysis of 100
samples taken in the Valencian Community revealed that, in soil, up to 5 μg kg−1 CTC, 15 μg kg−1 OTC, 18 μg kg−1 TC, and 12 μg kg−1 DC could be detected. Detection of the analytes in several samples, which typify great part of the Spanish agricultural soils,
should be outlined as most important result of this study.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
3.
Moroney C Lehane M Braña-Magdalena A Furey A James KJ 《Journal of chromatography. A》2002,963(1-2):353-361
Azaspiracids have been identified as the cause of a new toxic syndrome called azaspiracid poisoning (AZP) that has led to incidents of human intoxications throughout Europe following the consumption of mussels. Although five AZP toxins have been structurally elucidated to-date, azaspiracid (AZA1), 8-methylazaspiracid (AZA2) and 22-demethylazaspiracid (AZA3) are the predominant toxins. Separation of the three main AZP toxins was achieved using reversed-phase liquid chromatography (LC) and coupled to an electrospray ionisation source of an ion-trap mass spectrometer. Five reversed-phase (C18) and three diol solid-phase extraction (SPE) cartridges were compared for their efficacy in the cleanup of shellfish matrix. The comparison was based on the optimum recoveries of AZA1, AZA2 and AZA3 from extracts of mussel tissues. LC-electrospray MS3 analysis was used to quantify the AZP toxins in wash and eluate fractions in the SPE studies. Good recovery and reproducibility data were obtained for one diol SPE cartridge and two C18 SPE cartridge types. 相似文献
4.
Misako Tagiri-Endo Shigeru Suzuki Tomoyuki Nakamura Takashi Hatakeyama Kazuo Kawamukai 《Analytical and bioanalytical chemistry》2009,393(4):1367-1375
A simple and quick online solid-phase extraction (SPE) coupled to liquid chromatography (LC)/tandem mass spectrometry (MS/MS)
for the determination of the five antibiotics (florfenicol, FF; lincomycin, LCM; oxytetracyclin, OTC; tylosin, TS; valnemulin,
VLM) in swine wastewater has been developed. After filtration, aliquots (100 μl) of wastewater samples were directly injected
to a column-switching LC system. Some matrix interference was removed by washing up SPE column with 0.2% formic acid solution
and acetonitrile. Antibiotics eluted from SPE column were separated on analytical column by converting switching valve and
were detected by MS/MS. Calibration curves using the method of standard addition had very good correlation coefficients (r > 0.99) in the range of 0.1 to 2 ng/ml. The intra-day precision of the method was less than 12% and the inter-day precision
was between 6 to 17%. The detection limits were 0.01–0.1 ng/ml. When this method was applied to wastewater samples in swine
facilities, four compounds (LCM, OTC, TS, and VLM) were detected. 相似文献
5.
Guomin Wang Jian Zhao Tao Peng Dongdong Chen Cunxian Xi Xiong Wang Jinzhong Zhang 《Journal of separation science》2013,36(4):796-802
Matrix effects in determination of three β‐receptor agonists including salbutamol (SAL), clenbuterol, and terbutaline in animal‐derived foodstuffs were studied by ultra‐performance LC‐MS/MS with cleanup of immunoaffinity SPE column (IAC). Some animal tissue samples including pig liver, swine muscle, and fish muscle were hydrolyzed by the mixed enzyme solution or HCl solution, and the cleanup efficiencies with SAL IAC, MCX SPE column, and C18‐SCX tandem columns were examined and compared by using spiked experiments. The results showed that the matrix effects in the determination of SAL and terbutaline can be eliminated with SAL IAC cleanup, and the average recoveries of SAL were 77.4~81.5%, 79.0~80.3%, and 85.0~87.2% in pig liver, swine muscle, and fish muscle, respectively. The decision limit (ccα) and detection capability (ccβ) for SAL in pig liver were 0.02 and 0.05 μg/kg, respectively. 相似文献
6.
本文结合双层固相萃取和液相色谱-串联质谱法(LC-MS/MS),建立了水稻中内源性独角金内酯(Strigolactone,SLs)的快速分析方法。水稻根提取液经过石墨化炭黑/混合模式阴离子交换吸附剂+混合模式阳离子交换吸附剂(GCB/MAX+MCX)双层固相萃取柱除杂后,通过LC-MS/MS法分析检测。实验优化了固相萃取条件,并进行了方法学验证。结果表明,SLs在对应范围内线性关系良好(相关系数大于0.9972),方法检出限(S/N=3)为0.007~0.028ng/g,回收率为82.1%~115.8%,相对标准偏差(n=6)在1.9%~14.1%之间。建立的方法灵敏度高、重现性好,可用于水稻中内源性SLs的准确定量。 相似文献
7.
Anna Martínez-Villalba Encarnación Moyano Claudia P. B. Martins Maria Teresa Galceran 《Analytical and bioanalytical chemistry》2010,397(7):2893-2901
In this work a fast liquid chromatography (LC)–tandem mass spectrometry (MS/MS) method was developed for the analysis of toltrazuril,
a coccidiostatic drug, and its metabolites in meat food products. The applicability of atmospheric pressure chemical ionization
(APCI) and heated electrospray ionization in both positive and negative modes was studied. APCI in negative mode provided
the best results and the base peak originated from the loss of CF3 (toltrazuril and toltrazuril sulfone) and CHF3• (toltrazuril sulfoxide) was used as the precursor ion in MS/MS. A fast LC separation on a C18 Fused-Core™ column was used together with the APCI-MS/MS method developed using enhanced mass resolution mode (highly selective
selected reaction monitoring, H-SRM) to improve the sensitivity and selectivity for the analysis of these compounds in food
samples. A simple sample treatment based on an extraction with acetonitrile and a cleanup with a C18 cartridge was used. The LC-MS/MS (H-SRM) method showed good precision (relative standard deviation lower than 10%), accuracy,
and linearity and allowed the determination of these compounds in food samples down to the parts per billion level (limits
of detection between 0.5 and 5 μg kg-1). 相似文献
8.
Benzylpiperazine (BZP) is an amphetamine-type stimulant, which was legally available in New Zealand and widely used in “Party
Pills” until reclassification as a Class C drug in April 2008. BZP was included as part of a multi-analyte method developed
for hair screening using high-performance liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS). A 20-mg sample
of hair is extracted and partially purified using mixed-mode solid-phase extraction cartridges prior to analysis by LC-MS/MS.
The method was developed as a broad screen for drugs of abuse (including amphetamines, opiates, and benzodiazepines), with
only the BZP results being presented here. The assay was validated and found to be linear over the range of 0.085 to 8.65 ng/mg
with correlation coefficient of r
2 ≥ 0.99. Blank hair samples spiked with BZP at 0.22 and 2.16 ng/mg gave intra- and inter-day precision coefficients of variation
of ≤10% (n = 6 per day, 3 days) at both levels and calculated extraction efficiencies of 78% and 91%, respectively. The results from
the samples submitted to the laboratory for BZP analysis showed 11% were positive (n = 126). The mean BZP level was 3.9 ng/mg (range, 0.4–33 ng/mg; the result was extrapolated when above the calibration). These
data are the first available showing the levels expected from users of BZP. 相似文献
9.
In response to recent discoveries of acrylamide in heated foods, a solid-phase extraction and cleanup protocol was developed for the determination of acrylamide in fried or baked potato samples by liquid chromatography/mass spectrometry (LC/MS). The analyte was extracted from the matrix by using 2M NaCl, and an aliquot of the initial extract was loaded onto a reversed-phase cartridge. After the analyte was eluted from the cartridge, the eluate was cleaned up on a mixed-mode cation-exchange cartridge. The eluate was then evaporated, and the residue was reconstituted in mobile phase before LC/MS analysis. Recoveries, based on the recovery of an added internal standard, ranged from 96 to 101% with relative standard deviations (RSDs) of 5-11%. The response was linear for a concentration range of 100-2000 ng/g with a coefficient of determination (R2) of 0.992 (n = 25). An interday study showed good accuracy and precision of the method over a 3-day period with a recovery of 98% and an RSD of 9.5% (n = 15). The analyses of 6 potato chip samples showed concentrations of incurred acrylamide ranging from 260 to 1500 ng/g. 相似文献
10.
液相色谱-串联质谱法同时检测饲料中7种精神类药物 总被引:1,自引:0,他引:1
建立了液相色谱-串联质谱同时检测饲料样品中7种精神类药物(硝西泮、奥沙西泮、氯丙嗪、异丙嗪、地西泮、奋乃静、硫利达嗪)的方法.通过对提取溶剂、净化等预处理条件及LC-MS/MS 分析条件的优化,可以同时检测饲料中7种违禁精神类药物.饲料样品经乙腈/水(9:1, V/V)提取后,过MCX固相萃取柱净化,氮吹至干,用1 mL乙腈/水(2:8, V/V)溶解后测定,采用SRM模式进行定性与定量分析.7种精神类药物在饲料中的回收率为53.9%~110.2%; 相对标准偏差为3.4%~18.4%;硝西泮、奥沙西泮、氯丙嗪、异丙嗪的检出限为1.0 ng/g;对地西泮、奋乃静、硫利达嗪的检出限为5.0 ng/g.结果表明,本方法可用于饲料中7种精神类药物的测定. 相似文献
11.
A solid-phase extraction (SPE) and liquid chromatographic (LC) method was developed for the determination of selected fluoroquinolone (FQ) drugs including ofloxacin, norfloxacin, and ciprofloxacin in municipal wastewater samples. Extraction of the FQs was carried out with a weak cation exchanger SPE cartridge, the Oasis WCX. The cartridge was washed with water and methanol as a cleanup before the FQs were eluted by a mixture of methanol, acetonitrile, and formic acid. Separation of the FQs was achieved by using a Zorbax SB-C8 column under isocratic condition at a flow rate of 0.2mL/min. Recoveries of the FQs in spiked final effluent samples were between 87 and 94% with a relative standard deviation of less than 6%. Several techniques have been evaluated for the detection of FQs in sewage extracts; they included fluorescence detection and electrospray ionization (ESI) mass spectrometry using either mass-selective detection or tandem mass spectrometry (MS/MS). When they were applied to sewage influent and effluent samples, the LC-MS/MS technique operating in the multiple reaction monitoring (MRM) mode proved to be best suited for the determination of FQs in sewage samples as it provided the highest sensitivity (limit of quantification 5ng/L) and selectivity. The observation of signal suppression (matrix effect) for some FQs in ESI LC-MS and LC-MS/MS is discussed and a solution is proposed. The three FQs were detected in all the sewage samples tested in this work, with median concentrations between 34 and 251ng/L. 相似文献
12.
A method involving solid-phase extraction (SPE) and reversed-phase liquid chromatography–mass spectrometry (LC–MS) has been
developed for determination, in groundwater, of nitrobenzoic acids associated with 2,4,6-trinitrotoluene production. Pre-concentration
on a co-polymer-based SPE cartridge enabled quantitative extraction of the analytes from water. Investigation of negative
ion electrospray and atmospheric-pressure chemical ionization mass spectrometry indicated the sensitivity of APCI was more
than twice that of ESI. An 15N-labeled internal standard was used to achieve more accurate quantitation and mass assignment. Recovery was better than 80%
when 10 mL water was extracted with the SPE cartridge. Combination of SPE with LC–MS analysis resulted in method detection
limits of less than 5 μg L−1. The method has been used for analysis of groundwater samples collected from a site of a former ammunition plant. Contamination
with nitrobenzoic acids was determined at μg L−1 levels. 相似文献
13.
Application of a mixed-mode solid-phase extraction and cleanup procedure for LC/MS determination of thiabendazole and carbendazim in apple juice 总被引:2,自引:0,他引:2
Recently, a mixed-mode solid-phase extraction (SPE) procedure was developed for rapid extraction and cleanup for determination of the fungicides thiabendazole and carbendazim in various fruit juices. This paper reports the application of that sample preparation procedure to the liquid chromatographic/mass spectrometric determination of these fungicides in apple juice with detection by positive electrospray ionization mass spectrometry (ESI/MS). Response was linear for sample concentrations from 2 to 500 microg/L (ppb). Recoveries averaged 74% (9% RSD) for carbendazim and 93% (9% RSD) for thiabendazole. After SPE cleanup, no matrix supression was observed for the ESI+ response for either compound studied. The method was applied to the analysis of incurred residues in 4 store-bought apple juices; carbendazim levels ranged from 10 to 70 microg/L and thiabendazole levels ranged from less than 2 to 130 microg/L. 相似文献
14.
A liquid chromatographic method with comfirmation by capillary electrophoresis was used to determine 12 sulfonylurea herbicides in agricultural water. Analysis of 3 different water matrixes fortified at 2 levels gave good recoveries with adequate sensitivity at the 0.1 ppb level. A portion of the water was acidified with acetic acid and loaded onto an RP-102 solid-phase extraction (SPE) cartridge, and the extract was cleaned up on an alumina SPE cartridge. Extracts were desalted with an RP-102 SPE cartridge before instrumentation. Samples needing chemical filtration, such as pond water, required additional cleanup with a SAX SPE cartridge before the alumina cleanup step. Data were compiled for both determinative techniques and evaluated. 相似文献
15.
Carpinteiro I Abuin B Ramil M Rodríguez I Cela R 《Analytical and bioanalytical chemistry》2012,402(7):2471-2478
An improved selectivity method for the simultaneous determination of four benzotriazoles (benzotriazole, 4-methylbenzotriazole,
5-methylbenzotriazole, and 5,6-dimethyl-1H-benzotriazole) and six benzothiazoles (benzothiazole, 2-hydroxybenzothiazole, 2-benzothiazolamine, mercaptobenzothiazole,
2-methylbenzothiazole, and 2-methylthiobenzothiazole) in aqueous matrices has been developed. Under optimal conditions, analytes
are concentrated using a MAX solid-phase extraction (SPE) cartridge, based on divinylbenzene-N-vinylpyrrolidone functionalized with quaternary amine groups, which allows reversed-phase interactions in combination with
ionic exchange. Selected compounds are recovered with methanol–acetone 7:3 (v/v) whereas acidic interferences remained attached to the sorbent, and as determined by liquid chromatography coupled to tandem
mass spectrometry (LC-MS/MS), LOQs for surface, urban and industrial wastewater are in the range of 0.002–0.29 ng/mL. Figures
of merit of the method revealed good precision (RSD% <12%), linearity (R
2 > 0.99) and accuracy (%R = 80–100%) for surface waters and effluents allowing direct external standard quantification. For more complex samples, such
as urban and industrial raw wastewater, either the standard addition method or pseudo-external standard calibration using
matrix matched standards are recommended. Analysis of different real samples, surface, urban wastewater and, for the first
time, metal industry wastewater, reflected concentrations up to 310 ng/mL. The methylbenzotriazole isomers ratio was also
determined. 相似文献
16.
A method using solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the determination of 12 beta-blockers and beta(2)-agonists in wastewater samples. Extraction of the drugs was effected by an Oasis MCX cartridge with a strong cation resin adsorbent. Matrix coextractives were removed from the SPE cartridge by methanol prior to the elution of the drugs with a mixture of dichloromethane, 2-propranol, and ammonium hydroxide. The extract was analyzed by LC-MS/MS with electrospray ionization operating in the positive mode. Recovery of the 12 compounds was in most cases better than 85% at the fortification levels of 500 and 50 ng/L, with standard deviations between 3 and 7%. Based on a concentration factor of 250, the method detection limits ranged from 6 to 11 ng/L for the target compounds. No degradation of these drugs in spiked sewage effluent samples was observed over a storage period of 7 days at 4 degrees C in the dark. Many beta-blockers were detected in the 14 wastewater samples collected from seven Canadian sewage treatment plants; those occurring at the highest concentrations were atenolol, acebutolol, sotalol, and metroprolol, with overall median concentrations of 1370, 339, 282, and 257 ng/L, respectively. However, there was only a small decrease in the median concentrations of these beta-blockers between the primary and final effluent, suggesting that these drugs are not easily removed by the sewage treatment processes. As a result of selective extraction and effective removal of coextractives, no matrix effect was observed for the samples during LC-MS/MS analyses. 相似文献
17.
Ciminiello P Dell'Aversano C Dello Iacovo E Fattorusso E Forino M Tartaglione L Rossi R Soprano V Capozzo D Serpe L 《Analytical and bioanalytical chemistry》2011,401(3):1043-1050
Blooms of Ostreopsis spp. have been recently reported along the Mediterranean coasts of Spain, France, Italy, and Greece posing serious risks
to human health. Occurrence of Ostreopsis spp. may result in palytoxin contamination of seafood and, in order to prevent sanitary risks, the need exists to develop
efficient extraction procedures to be coupled to rapid and sensitive monitoring methods of palytoxin-like compounds in seafood.
In the present study, the best conditions for both extraction of palytoxin from seafood and palytoxin quantification by using
liquid chromatography tandem mass spectrometry (LC-MS/MS) were investigated. Three seafood matrices (mussels, sea-urchins,
and anchovies) were selected and five different extraction systems were tested, namely: the official protocol for extraction
of lipophilic toxins and various aqueous methanol or acetonitrile solutions (MeOH/H2O 1:1, MeOH/H2O 8:2, MeCN/H2O 8:2 and MeOH 100%). Extraction with MeOH/H2O 8:2 provided the best results in terms of accuracy and matrix interference on LC-MS/MS detection of palytoxin. Accuracy
and intra-day reproducibility (n = 3) were evaluated for all the selected matrices but only for mussels at three spiking concentration levels, including the
provisional limit proposed by the Community Reference Laboratory for marine biotoxins (250 μg kg−1). Limits of quantitation of palytoxin in mussels, sea-urchins and anchovies tissues were calculated using matrix-matched
standards; taking into account extraction efficiency of MeOH/H2O 8:2, they resulted to be 228, 343, and 500 μg kg−1, respectively. 相似文献
18.
An ion exchange solid phase extraction (SPE) strategy is developed for application with liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) for characterization of central carbon metabolites involved in methane assimilation and adjacent pathways in natural mixtures. For this purpose, short-time microcosm samples were obtained from lake sediment known to consume methane. Three SPE procedures were developed for the recovery of 51 targeted metabolites from five compound classes (amino acids, carboxylic acids, sugar phosphates, nucleotides and acyl-CoAs). The three SPE procedures employed were mixed mode (i) strong cation exchange, (ii) strong anion exchange and (iii) weak anion exchange. By spiking stable isotopic labeled standards, validation of the SPE procedures for the sediment extracts demonstrated that a 3 cm(3), 60 mg SPE sorbent bed provided effective loading capacity for targeted metabolites with an analytical variation of 16% RSD. We readily analyzed 32 of the targeted 51 metabolites using LC-MS/MS after sediment sample extraction, cleanup and pre-concentration. The remaining 19 targeted metabolites were either at, or below, the limit of detection. The current approach provides a good workflow for absolute quantification of intermediates in C(1)-carbon metabolism in natural microbial communities. 相似文献
19.
Bruins CH Jeronimus-Stratingh CM Ensing K van Dongen WD de Jong GJ 《Journal of chromatography. A》1999,863(1):115-122
The potential of the direct coupling of solid-phase extraction (SPE) with mass spectrometry (MS) for the analysis of biological samples is demonstrated. For SPE a cartridge exchanger is used and the eluate is directly introduced into the mass spectrometer. This system has been investigated for the determination of clenbuterol in urine. With mixed-mode cartridges, a considerable ion suppression has been obtained. The mass spectrum at the elution time of clenbuterol is dominated by that of creatinine and adduct formation of clenbuterol and creatinine has been observed. The whole procedure including injection of 1 ml urine, washing and desorption has been developed with cartridges containing 8-microm C18-bonded silica. If only a single MS step is used, the selectivity and, therefore, the sensitivity are insufficient. The detection limit is about 100 ng/ml. However, with atmospheric pressure chemical ionisation and the tandem MS mode the detection limit has been decreased to about 2 ng/ml and the ion suppression is only about 10%. For the electrospray ionisation the detection limit is about 10-times higher and the ion suppression is less favourable. The repeatability for the SPE-MS-MS procedure was 6.5% at 10 ng/ml (n=5) and the difference between the response factors at 10 ng/ml and 100 ng/ml was only 2.5%. The MS behaviour of clenbuterol and the matrix under the present conditions is discussed. 相似文献
20.
Steven Ray Wilson Mikolai Jankowski Milaim Pepaj Albena Mihailova Fernando Boix Gabriel Vivo Truyols Elsa Lundanes Tyge Greibrokk 《Chromatographia》2007,66(7-8):469-474
A 2D liquid chromatography (LC) system using hydrophilic interaction chromatography (HILIC) and reversed phase columns has
been employed for comprehensive (LC × LC) separation of rat muscle tissue micro-dialysate. Incorporation of an on-line reverse-phase
solid phase extraction (SPE) enrichment column in front of the first dimension enabled aqueous samples with high salt concentrations
to be injected directly without compromising the chromatographic performance of the HILIC column. Since the SPE enrichment
column allowed injection of large sample volumes (e.g. 450 μL), a capillary HILIC column (inner diameter 0.3 mm) could be
employed instead of a larger column which is often used in the first dimension to load sufficient amounts of sample. The two
chromatographic dimensions were connected using a column selector system with 18, 1.0 mm I.D. C18 “transition” SPE columns. A PLRP C18 column was used in the second dimension. The 2D LC system’s performance was evaluated with a tryptic digest mixture of three
model proteins. Good trapping accuracy (HILIC→transition SPE→RP recovery >95%) and repeatability (within-and between day retention
time RSDs of first and second dimension chromatography >1%) was achieved. A dialysis sample of rat muscle tissue was separated
with the 2D system, revealing complexity and large differences in concentrations of the various compounds present, factors
which could potentially interfere with the quantification and monitoring of two target analytes, arg-bradykinin and bradykinin.
Subsequently, “Heart-cut” 2D LC-electrospray–mass spectrometry (ESI–MS) with post-column on-line standard injection was employed
to monitor arg-bradykinin and bradykinin levels as a function of various muscle conditions. The method’s quantification precision
was RSD = 3.4% for bradykinin. 相似文献