固相萃取–气相色谱–负化学源质谱法检测水果和蔬菜中的毒杀芬

采用改进的分散固相萃取(QuEchERs)法对样品进行前处理,建立水果和蔬菜中毒杀芬残留的气相色谱–负化学电离源质谱(GC–NCI–MS)检测方法。样品中的毒杀芬由正己烷提取,经吸附剂PSA+GCB净化,在GC–NCI–MS的选择离子扫描模式下进样分析。毒杀芬的色谱保留时间在12.5~18.0 min区间内,采用面积归一化法积分,外标法定量。毒杀芬质量浓度在0.050~2.000 mg/L范围内与色谱峰面积呈良好的线性关系,相关系数r=0.999 1。分别以蓝莓、黄桃、菠菜为基质,在0.025,0.050 mg/kg添加水平下,毒杀芬的回收率为107.2%~118.1%,测定结果的相对标准偏差为5.5%~8.8%(n=6),定量限为0.025 mg/kg。该方法检测快速,适用于水果和蔬菜中毒杀芬残留的日常检测。     

高效液相色谱-串联质谱法测定水果中残留的烯唑醇

建立了水果中烯唑醇残留量的高效液相色谱-串联质谱（LC-MS/MS）测定方法。样品采用丙酮-正己烷液液振荡提取,经分散固相萃取（DSPE）净化后,采用ODS-C18柱为分离柱,以乙腈-0.1％甲酸溶液为流动相,采用液相色谱-串联质谱(ESI)多反应监测（MRM）正离子模式测定,外标法定量。烯唑醇在0.002～0.2 mg//L质量浓度范围内线性关系良好,方法定量下限（LOQ）为0.001 mg/kg。在0.005～0.1 mg/kg之间的3个添加浓度水平下,添加回收率为78.8 %~108.0 %,相对标     

Rapid determination of nineteen chlorophenols in wood, paper, cardboard, fruits, and fruit juices by gas chromatography/mass spectrometry.

Although the use of pentachlorophenol (PCP) is prohibited in most countries, it is still widely found in the wood of pallets, containers, crates and in cardboard, paper, etc. Such material may contain not only PCP but other chlorophenols as well. Wooden crates and cardboard boxes are often used to store and transport fresh fruits. Consequently, chlorophenols present in the wood may contaminate the stored fruits by migration. To ascertain that packaging, storage material, and fruit raw materials are free from chlorophenol residues, we developed a rapid and sensitive method for the detection of 19 chlorophenols by gas chromatography/mass spectrometry (GC/MS). The test portions are directly extracted and acetylated in a solution of sodium carbonate in the presence of acetic anhydride and hexane. The hexane layer is analyzed, without further purification, by GC/MS in the selective-ion monitoring mode. The method allows the analysis of >40 samples/day with detection limits of <20 microg/kg for chlorophenols in wood, cardboard, and paper, and <2 microg/kg for chlorophenols in fruits. Typical recoveries of all chlorophenols were 94% from paper, 115% from cardboard, 51% from wood (depending on the size of the chips or shavings), and 93% from fruit puree.     

Determination of spiroxamine residues in grapes, must, and wine by gas chromatography/ion trap-mass spectrometry

Analytical methodology was developed and validated for the determination of spiroxamine residues in grapes, must, and wine by gas chromatography/ion trap-mass spectrometry (GC/IT-MS). Two extraction procedures were used: the first involved grapes, must, and wine extraction with alkaline cyclohexane-dichloromethane (9 + 1, v/v) solution, and the second grape extraction with acetone, dichloromethane, and petroleum ether. In both procedures, the extract was centrifuged, evaporated to dryness, and reconstituted in cyclohexane or 2,2,4-trimethylpentane-toluene (9 + 1, v/v), respectively. Spiroxamine diastereomers A and B were determined by GC/IT-MS, and a matrix effect was observed in the case of grapes but not in must and wine. Recovery of spiroxamine from fortified samples at 0.02 to 5.0 mg/kg ranged from 78-102% for grapes and must, with relative standard deviation (RSD) <13%; for red and white wines, recoveries ranged from 90 to 101% with RSD <9%. The limit of quantification was 0.02 mg/kg for grapes, must, and wine or 0.10 mg/kg for grapes, depending on the extraction procedure used.     

基于壳聚糖的QuEChERS-气相色谱-串联质谱法测定人参中30种农药残留

建立了一种以壳聚糖为净化材料的QuEChERS-气相色谱-串联质谱检测人参中30种农药残留的检测方法。探究了吸附剂及其用量对样品提取和净化效果的影响,确定壳聚糖为吸附剂净化。采用选择离子监测(SRM)模式,基质匹配标准曲线外标法定量。30种农药在各自的浓度范围内,线性关系良好(r> 0.996);检出限范围为1.5~3.0μg/kg,定量限范围为5.0~10.0μg/kg。3个添加水平(10,20,100μg/kg)的回收率在84.1%~113.7%之间,相对标准偏差均小于15%。该方法适用于检测人参中农药残留。     

固相萃取–气相色谱–串联质谱法测定茶叶中9种农药残留量

建立固相萃取净化–气相色谱–串联质谱法同时测定茶叶中9种农药残留量的方法。茶叶样品用乙腈均质提取,提取液经固相萃取净化处理后,采用DB–5MS毛细管色谱柱分离,在多反应监测模式下测定,外标法定量。9种农药组分的质量浓度在0.01~0.50 mg/L范围内与其色谱峰面积呈良好线性,相关系数r~2大于0.998,方法测定下限(10 S/N)为0.002~0.01 mg/kg。以空白绿茶、红茶、普洱茶和乌龙茶为基体,在0.05,0.1,0.2 mg/kg 3个添加水平进行加标回收试验,加标回收率在73.6%~99.7%之间,相对标准偏差为4.2%~8.7%(n=6)。该法操作简便、快速,适用于茶叶中多种农药残留的测定。     

Residue analysis of kresoxim‐methyl and boscalid in fruits,vegetables and soil using liquid–liquid extraction and gas chromatography–mass spectrometry

A GC‐MS procedure for simultaneously determining and validating kresoxim‐methyl and boscalid has been developed in fruit, vegetable and soil matrices. The method was based on one‐step liquid–liquid extraction with acetone and dichloromethane solvents. Estimated limits of detection (LODs) for kresoxim‐methyl and boscalid were 0.006 and 0.015 mg/kg, and limits of quantification (LOQs) were 0.02 and 0.05 mg/kg, respectively. The intra‐ and inter‐ precision were achieved with RSD better than 13.8 and 14.5%, and recoveries were in the range of 77.1–98.7% for kresoxim‐methyl and 72.8–105.1% for boscalid. The expanded uncertainties calculated at 0.1 mg/kg were below 18%. Concentration levels for residues of the two fungicides in melon samples from field trials collected 7 days after the last application were clearly below the established MRL values. Copyright © 2009 John Wiley & Sons, Ltd.     

固相萃取-气相色谱/质谱法分析水果和蔬菜中残留的嘧菌酯

建立了多种水果和蔬菜中嘧菌酯残留的气相色谱/质谱分析方法。首先用乙酸乙酯-环己烷(体积比为1∶1)对样品中的嘧菌酯进行超声波提取,经硅胶固相萃取小柱对样品提取液进行净化、富集,采用气相色谱/质谱法以选择离子监测模式(m/z 344,372,388,403定性,m/z 344定量)进行检测。实验结果表明,嘧菌酯在0.01～1.0 mg/kg浓度范围内呈线性,其相关系数r>0.99。在低、中、高3个添加水平,嘧菌酯的回收率为85.2%～98.2%,相对标准偏差为5.8%～21.5%。方法的检测限不大于0.01 mg/kg,定量限不大于0.05 mg/kg。     

Multiwalled carbon nanotubes as a solid-phase extraction adsorbent for the determination of three barbiturates in pork by ion trap gas chromatography-tandem mass spectrometry (GC/MS/MS) following microwave assisted derivatization

A new method was developed for the rapid screening and confirmation analysis of barbital, amobarbital and phenobarbital residues in pork by gas chromatography-tandem mass spectrometry (GC/MS/MS) with ion trap MSD. The residual barbiturates in pork were extracted by ultrasonic extraction, cleaned up on a multiwalled carbon nanotubes (MWCNTs) packed solid phase extraction (SPE) cartridge and applied acetone-ethyl acetate (3:7, v/v) mixture as eluting solvent and derivatized with CH3I under microwave irradiation. The methylated barbiturates were separated on a TR-5MS capillary column and detected with an ion trap mass detector. Electron impact ion source (EI) operating MS/MS mode was adopted for identification and external standard method was employed for quantification. One precursor ion m/z 169 was selected for analysis of barbital and amobarbital and m/z 232 was selected for phenobarbital. The product ions were obtained under 1.0 V excitation voltage. Good linearities (linear coefficient R > 0.99) were obtained at the range of 0.5-50 microg kg(-1). Limit of detection (LOD) of barbital was 0.2 microg kg(-1) and that of amobarbital and phenobarbital were both 0.1 microg kg(-1) (S/N > or = 3). Limit of quantification (LOQ) was 0.5 microg kg(-1) for three barbiturates (S/N > or = 10). Satisfying recoveries ranging from 75% to 96% of the three barbiturates spiked in pork were obtained, with relative standard deviations (R.S.D.) in the range of 2.1-7.8%.     

An alternative and fast method for determination of glyphosate and aminomethylphosphonic acid (AMPA) residues in soybean using liquid chromatography coupled with tandem mass spectrometry

A simple and specific method using reversed‐phase liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) was investigated, which allowed the determination of residues of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in soybean samples. An aqueous extraction with liquid‐liquid partition followed by protein precipitation was performed before the LC/MS/MS determination. The quantitation of glyphosate and AMPA was performed in positive and negative ESI mode, respectively, using the multiple reaction monitoring (MRM) mode with three transitions for each analyte to enhance the specificity of the method and avoid false positives. The methodology reported in this work is capable of detecting residues of glyphosate and AMPA in soybean samples with limits of quantification of 0.30 and 0.34 mg kg^?1, respectively. This alternative method has throughput advantages such as simpler sample preparation and faster chromatographic analysis. Copyright © 2009 John Wiley & Sons, Ltd.     

Analysis of pesticide residues using the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) pesticide multiresidue method in combination with gas and liquid chromatography and tandem mass spectrometric detection

The Quick Easy Cheap Effective Rugged and Safe multiresidue method (QuEChERS) has been validated for the extraction of 80 pesticides belonging to various chemical classes from various types of representative commodities with low lipid contents. A mixture of 38 pesticides amenable to gas chromatography (GC) were quantitatively recovered from spiked lemon, raisins, wheat flour and cucumber, and determined using gas chromatography-tandem mass spectrometry (GC-MS/MS). An additional mixture of 42 pesticides were recovered from oranges, red wine, red grapes, raisins and wheat flour, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for determination. The pesticides chosen for this study included many of the most frequently detected ones and/or those that are most often found to violate the maximum residue limit (MRL) in food samples, some compounds that have only recently been introduced, as well as a few other miscellaneous compounds. The method employed involved initial extraction in a water/acetonitrile system, an extraction/partitioning step after the addition of salt, and a cleanup step utilizing dispersive solid-phase extraction (D-SPE); this combination ensured that it was a rapid, simple and cost-effective procedure. The spiking levels for the recovery experiments were 0.005, 0.01, 0.02 and 0.2 mg kg(-1) for GC-MS/MS analyses, and 0.01 and 0.1 mg kg(-1) for LC-MS/MS analyses. Adequate pesticide quantification and identity confirmation were attained, even at the lowest concentration levels, considering the high signal-to-noise ratios, the very good accuracies and precisions, as well as the good matches between the observed ion ratios. Mean recoveries mostly ranged between 70 and 110% (98% on average), and relative standard deviations (RSD) were generally below 10% (4.3% on average). The use of analyte protectants during GC analysis was demonstrated to provide a good alternative to the use of matrix-matched standards to minimize matrix-effect-related errors. Based on these results, the methodology has been proven to be highly efficient and robust and thus suitable for monitoring the MRL compliance of a wide range of commodity/pesticide combinations.     

Application of LPME/GC-ECD for determination of PCP in water

PCP with a variety of application in industrial, agricultural and domestic fields, is an inhibitor of oxidative phosphorylation, therefore, toxic to a broad spectrum of organisms and may have mutagenic properties [1]. In China, sodium pentachlorophenate (Na-PCP) has been sprayed widely since the 1960s to control the spread of snailborne schistosomiasis. Although Na-PCP has been replaced by some new molluscicides since 1990s, the persistence of PCP has resulted in the accumulation in soil …     

Residue determination of captan and folpet in vegetable samples by gas chromatography/negative chemical ionization-mass spectrometry

A gas chromatography/negative chemical ionization-mass spectrometry (GC/NCI-MS) method has been developed for the simultaneous determination of the fungicides captan and folpet in khaki (persimmon; flesh and peel) and cauliflower. Samples were extracted with acetone in the presence of 0.1 M zinc acetate solution in order to avoid degradation of fungicides and were purified using solid-phase extraction with divinylbenzene polymeric cartridges. Purified extracts were evaporated and dissolved in hexane prior to injection into the GC/NCI-MS system. Isotope-labeled captan and folpet were used as surrogate/internal standards, and quantification was performed using matrix-matched calibration. The method showed linear response in the concentration range tested (50-2500 ng/mL). The method was fully validated with untreated blank samples of khaki (flesh and peel) and cauliflower spiked at 0.05 and 0.5 mg/kg. Satisfactory recoveries between 82 and 106% and relative standard deviations lower than 11% in all cases (n = 5) were obtained. The limit of detection for both compounds were estimated to be 0.01 mg/kg. The developed method has been applied to treated and untreated samples collected from residue trials.     

加速溶剂萃取-气相色谱-串联质谱法测定茶叶中10种吡唑和吡咯类农药的残留量

建立了加速溶剂萃取(ASE)-气相色谱-串联质谱(GC-MS/MS)法用于测定茶叶中10种吡唑和吡咯类农药残留。ASE萃取压力为1.03×107 Pa,萃取温度为100 ℃,萃取时间为5 min,萃取溶剂为乙酸乙酯-正己烷(1:1, v/v)。萃取循环1次,萃取液浓缩后用Envi-Carb/PSA固相萃取小柱净化,乙酸乙酯-正己烷(1:1, v/v)洗脱。洗脱液浓缩后,用正己烷定容,供GC-MS/MS测定,外标法定量。方法的准确度和精密度均符合残留分析要求。方法的定量限(LOQ)分别为唑螨酯0.003 mg/kg、氟虫腈硫化物0.001 mg/kg、氟虫腈0.002 mg/kg、氟虫腈砜化物0.005 mg/kg、溴虫腈0.002 mg/kg、氟硅唑0.006 mg/kg、野燕枯0.001 mg/kg、吡草醚0.001 mg/kg、吡螨胺0.0003 mg/kg、唑虫酰胺0.005 mg/kg。方法的灵敏度能满足各国有关农药的残留限量要求。     

Determination of seven benzoylphenylurea insecticides in processed fruit and vegetables using high-performance liquid chromatography/tandem mass spectrometry

A liquid chromatographic method with electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) has been developed for the sensitive and selective determination of seven benzoylphenylurea insecticide residues (diflubenzuron, triflumuron, lufenuron, flufenoxuron, teflubenzuron, chlorfuazuron, hexaflumuron) in pear baby purée, concentrated lemon juice, and tomato pulp. The general sample extraction/partition method for our established multiresidue methods has been used. The entire procedure involves extraction of residues with acetone and partition into ethyl acetate/cyclohexane. Chromatographic determination was performed using a C18 column and isocratic elution. Fourteen MS/MS transitions of precursor ions were monitored (two for each pesticide) using negative ESI. The majority of mean recoveries at fortification levels of 0.002-0.020 and 0.020-0.200 mg/kg were in the range 77-102% with relative standard deviations between 2 and 10%. The excellent sensitivity and selectivity of this LC/MS/MS method allowed quantitation and identification at low levels in difficult matrices with a run time of 4 min.     

Multiresidue analysis of pesticides in fruits and vegetables using solid-phase extraction and gas chromatographic methods

A new extraction and cleanup procedure with gas chromatography was developed for the sensitive determination of acephate, dimethoate, malathion, diazinon, quinalphos, chlorpyrifos, profenofos, alpha-endosulfan, beta-endosulfan, chlorothalonil and carbaryl using 1-chloro-4-fluorobenzene as an internal standard in fruits and vegetables. Several extracting and eluting solvents for solid-phase extraction were investigated. The overall extracting solvent with a mixture of acetone:ethyl acetate:hexane (10:80:10, v/v/v) and a eluting solvent of 5% acetone in hexane used with the RPC18 cartridge gave the best recovery for all of the investigated pesticides, and minimized the interference from co-extractants. Under the optimal extraction and clean-up conditions, recoveries of 85 - 99% with RSD < 5.0% (n = 3) for most of the pesticides at the 0.02 - 0.5 mg/kg level were obtained. The limit of detection was between 0.005 - 0.01 mg/kg and the limit of quantification was 0.01 mg/kg. This analytical procedure was characterized with high accuracy and acceptable sensitivity to meet requirements for monitoring pesticides in crops.     

快速高效液相色谱-串联质谱法同时测定水产品中5类33种药物残留

建立了快速高效液相色谱-串联质谱法(RRLC-MS/MS)同时测定水产品中四环素类、喹诺酮类、磺胺类、磺胺增效剂和三苯甲烷类共5大类33种药物残留的方法。样品用Na2EDTA-Mcllvaine缓冲溶液及乙腈提取,正己烷脱脂后,用RRLC进行分离。在电喷雾正离子模式下,以动态多反应监测(Dynamic MRM)方式采集数据进行定性与定量分析。33种药物在相应的浓度范围内线性良好,相关系数均大于0.99;在3个不同浓度添加水平下,平均回收率为63.6%～115.2%;相对标准偏差(RSD)为4.6%～14.6%;检出限(LOD,S/N=3)和定量限(LOQ,S/N=10)分别为0.1～2.0μg/kg和0.5～5.0μg/kg。本方法简便快速、灵敏可靠,适用于水产品中药物多残留的同时快速定性与定量测定。     

Ultrasound-Assisted Deep Eutectic Solvent Extraction of Anthocyanins from Blueberry Wine Residues: Optimization,Identification, and HepG2 Antitumor Activity

Blueberry wine residues produced during the wine-brewing process contain abundant anthocyanins and other bioactive compounds. To extract anthocyanins from blueberry wine residues more efficiently, a novel procedure of ultrasound-assisted deep eutectic solvent extraction (UADESE) was proposed in this work. The extraction process was optimized by response surface methodology coupled with genetic algorithm. The optimum extraction parameters to achieve the highest yield of anthocyanins (9.32 ± 0.08 mg/g) from blueberry wine residues by UADESE were obtained at water content of 29%, ultrasonic power of 380 W, extraction temperature of 55 °C, and extraction time of 40 min. The AB-8 macroporous resin combined with Sephadex LH-20 techniques was used to purify the crude extract (CE) obtained under optimum extraction conditions and analyze the anthocyanins composition by HPLC-ESI-MS/MS. The cyanidin-3-rutinoside with purity of 92.81% was obtained. The HepG2 antitumor activity of CE was better than that of the purified anthocyanins component. Moreover, CE could increase the intracellular reactive oxygen species levels and the apoptosis, and arrest HepG2 cells in the S phases. These findings provided an effective and feasible method for anthocyanins extraction, and reduced the environmental burden of this waste.     

Optimization of the Extraction and Analysis of Natural Androgen Steroids and Their Metabolites in Urine by GC/MS and GC/FID

A multiresidue method was developed for screening, quantification, and confirmation of nine natural androgen steroids and their metabolites in urine. Steroids were first extracted from urine by solid phase extraction, enzymatically deglucuronated, re-extracted using a liquid/liquid extraction for purification, and finally acetylated for GC/MS and GC/FID analysis. Each step of sample preparation, as well as analysis, was optimized: solid phase extraction, liquid/ liquid extraction, and derivatization reaction … Therefore, a rugged sample preparation procedure was developed leading to extracts of sufficient purity (recoveries >66% and few matrix compounds). The whole methodology allowed reliable detection and quantification of the nine steroids at low concentration levels. Linearity and repeatability were established and were found to be satisfactory (R² > 0.996, RSD < 11%). Finally, the method was applied to quantify compounds of interest in real samples collected from healthy volunteers and patients treated with 4-androstenedione or dehydroepiandrosterone.     

Determination of residues of endosulfan and five pyrethroid insecticides in virgin olive oil using gas chromatography with electron-capture detection

A simple, fast and economical method has been developed for the determination of endosulfan and five pyrethroid insecticides, cypermethrin, deltamethrin, fenvalerate, lambda-cyhalothrin and permethrin, in virgin olive oil. The method uses a Sep-Pak alumina-N column cleanup after a liquid-liquid extraction or low-temperature precipitation step, and gas chromatography (GC) with electron-capture detection. The matrix effect was assessed for the GC systems used. Recoveries were 71-91% with RSD values of 6-17%. The method was applied to 338 virgin olive oil samples for monitoring of residues of these pesticides. Cypermethrin and lambda-cyhalothrin were detected at the limit of quantification in one sample each, while 22% of samples contained endosulfan residues, mostly at very low levels ranging from 0.02 to 0.57 mg/kg.