分散固相萃取-超低温液液微萃取-气相色谱质谱法测定烟熏及烧烤肉制品中16种欧盟优控多环芳烃

建立了分散固相萃取-超低温液液微萃取-气相色谱质谱法测定烟熏及烧烤肉制品中16种欧盟优控多环芳烃的分析方法.样品用乙腈提取、上清液经分散固相萃取净化后在-80℃条件下采用甲苯液液微萃取浓缩,选用DB-EUPAH色谱柱(20 m×0.18 mm×0.14μm)分离,最后经质谱检测定量.结果表明,16种欧盟多环芳烃在5～5...     

基于分散液-液微萃取技术的石斛酚含量测定与分析

建立分散液-液微萃取与高效液相色谱联用技术测定石斛酚的分析方法。通过对实验条件的筛选及优化,得到最佳条件：pH 3,辅以涡旋方式进行萃取,萃取溶剂为120 μL正戊酸、萃取时间1 min,分散剂为曲拉通X-114、用量80 μL。此方法进行萃取,检出限为2.625 μg/L,定量限为8.74 μg/L,线性范围为0.10～30.00 mg/L,萃取富集倍数平均值为28.02,萃取回收率平均值为1.01。将建立的分析方法应用于实际石斛样品的测定,结果表明该方法能对石斛中的石斛酚进行高效萃取与富集,方法快速简便。     

Triple Quadrupole Mass Spectrometry with Liquid Chromatography and Dispersive Liquid-Liquid Microextraction for the Determination of Monoterpenes in Alcoholic Drinks

Five monoterpenes (linalool, geraniol, eugenol, carvacrol, and thymol) were directly preconcentrated from alcoholic drinks with no previous sample treatment step using a miniaturized technique based on dispersive liquid-liquid microextraction. Chloroform (300 μL) was rapidly injected into 8 mL of sample, while the addition of a disperser solvent was obviated because of the ethanol content of the alcoholic beverages. The enriched phase was evaporated, reconstituted in 50 μL water, and analyzed by reversed phase liquid chromatography with a mobile phase consisting of 25% acetonitrile (0.1% formic acid) and 75% water (0.1% formic acid) and tandem mass spectrometry with a triple quadrupole in the selected reaction monitoring mode. The matrix effect was evaluated, and quantification by the standard additions method is recommended. Limits of detection ranged from 0.003 to 1.5 ng mL^?1, depending on the compound and the matrix. Enrichment factors of between 12 and 88 were obtained. The method was validated through recovery tests, finding values in the 76–128% range. The intraday precision was lower than 20% in terms of relative standard deviation. Different types of alcoholic drinks were analyzed, monoterpenes being detected at concentrations from 0.4 to 627 ng mL^?1.     

气相色谱/质谱法测定白酒中的有机氯农药残留

建立了色谱-质谱、选择离子检测法（GC—MS—SM）测定白酒中有机氯农残的分析方法。白酒样品用Florisil固相萃取净化、氮吹浓缩，经HP-5MS弹性石英毛细管柱分离后进行质谱分析，采用选择离子监测模式，以保留时间和特征离子的丰度比定性，外标法定量。在最佳实验条件下，方法的检出限为0．4～1．2μg/L，相对标准偏差为2．3％～8．8％，样品加标回收率为81．0％～106．3％。该方法的灵敏度、准确度和精密度均能满足白酒中有机氯农残分析的要求。     

牛奶中有机氯农药及拟除虫菊酯农药多残留的HS-SPME-GC-MS分析方法研究

目的 建立牛奶中有机氯农药和拟除虫菊酯类农药的快速多残留测定方法.方法 以顶空固相微萃取作为前处理手段,采用气相色谱-质谱联用方法测定牛奶样品中31种农药组分（其中有机氯农药23种,拟除虫菊酯类农药8种）,并以13C6-六氯苯和13C10-灭蚁灵作为稳定的同位素内标物,采用内标法定量.结果 方法的最低检测限在0.002～0.2μg/L之间,回收率在85%～110%之间.相对标准差在3%～12%之间.结论 该方法快速、简单、准确、可靠、环保.适用于批量牛奶样品中农药残留的筛查.     

Fully Automated Vortex-Assisted Liquid-Liquid Microextraction Coupled to Gas Chromatography-Mass Spectrometry for the Determination of Trace Levels of Phthalate Esters in Liquor Samples

A fully automated vortex-assisted liquid-liquid microextraction (VALLME) system coupled to gas chromatography-mass spectrometry (GC/MS) was developed for the determination of phthalate esters (PAEs) in liquor samples. The whole analytical procedure, including spiking, extraction, phase separation, extractant collection, and GC/MS quantification, were automatically carried out. The use of a commercially available sample vial and a multipurpose sampler equipped with a highly efficient orbital vortex shaker facilitated the accessibility and automation of the method. Key factors, such as type and volume of the extractant, time and speed for VALLME, agitation speed and time required for phase separation, sample pH, salt effects, and matrix effects, were thoroughly investigated. Under the optimum conditions, linearity was in the range 0.05 to 120 μg L^?1. Limits of detection ranged from 0.003 to 0.006 μg L^?1. Enrichment factors were in the range 211 to 304. Reproducibility and recoveries were assessed by testing a series of liquor samples spiked with different concentrations of phthalate esters. This work provided an innovative way to automate the VALLME method and couple it on-line with GC/MS.     

GC-MS法测定芹菜中氟虫腈及其代谢物的残留量

建立同时检测芹菜中氟甲腈、氟虫腈硫醚、氟虫腈、氟虫腈砜4种农药残留的气质联用检测方法。样品经乙腈提取后,浓缩过石墨化炭黑/氨基固相萃取柱净化,洗脱液洗脱浓缩定容后检测。4种农药在0.01 mg/L~1.0 mg/L范围内线性关系良好(R≥0.999 2),平均回收率为82.9%~102.2%,精密度为2.18%~5.66%,均满足定量分析的要求。4种农药残留的定量限为0.002 mg/kg。     

气相色谱-质谱法测定茶叶中32种残留农药

建立了茶叶中多种农药残留的分析方法。粉碎后的茶叶样品以乙腈为提取溶剂经超声萃取,萃取液再经石墨化碳固相萃取柱净化,采用GC-EI-MS 的选择离子监测(SIM)方式和外标定量方法,同时分析测定了茶叶中的32 种农药残留量(17 种有机磷、8 种有机氯、4 种拟除虫菊酯、乙草胺、三唑酮和多效唑)。该方法回收率在48.2%～121.9% 之间,相对标准偏差小于18.3%,32 种农药的检出限最低为1.0μg/kg,最高为20μg/kg。该方法快速、灵敏、准确,各项技术指标满足国内外农药残留检测的要求,适合茶叶样品中痕量农药残留的分析。     

Gas Purge Microsyringe Extraction Coupled with Dispersive Liquid-Liquid Microextraction for the Determination of Acidic Compounds in Food Packaging Materials

A green, simple and sensitive method was developed for the analysis of volatile carboxylic acids (VFAs) and perfluorocarboxylic acids (PFCAs) in food packaging materials. The acidic compounds in food packaging materials were first extracted by gas purge microsyringe extraction (GP–MSE) with 1.0 mL 0.1 mol·L^?1 NaOH solution, then the analytes were dispersive liquid-liquid microextracted (DLLME) by 50 μL chloroform as extraction solvent and 200 μL acetonitrile as dispersive solvent. The 2-(5-Benzoacridine) ethyl-p-toluenesulfonate (BAETS) with excellent fluorescence property was applied to enhance the high performance liquid chromatography (HPLC) sensitivity. The obtained recoveries for the VFAs ranged from 92.0 to 101 %. The method LODs calculated at a signal-to-noise ratio (S/N) of 3 were in the range of 0.80–3.40 μg·kg^?1, while the LOQs calculated at S/N of 10 were in the range of 2.5–10.2 μg·kg^?1. All compounds were in good linearity with concentration coefficients of higher than 0.997. Perfluorooctanoic acid (PFOA) was found in all of the 15 kinds of samples analyzed with concentrations ranging from 4.86–7.56 μg·kg^?1. Acetic acid, butyric acid, and caprylic acid were found in half of the samples analyzed. The other analytes were also found in more than 30 % samples with concentrations varied between 3.96 and 293 μg·kg^?1.     

分散液液微萃取-气相色谱法测定复杂食品基质中对羟基苯甲酸酯类

建立复杂食品基质中对羟基苯甲酸酯类及其钠盐的分散液液微萃取(Dispersive Liquid-Liquid Microextraction,DLLME)-气相色谱(Gas Chromatography,GC)检测方法。样品浸泡在水中,经煮沸和超声两个步骤提取目标物质。取4 mL待测液,调节p H后分别加入0.6 g氯化钠,0.3 mL四氯化碳和0.6 mL丙酮,手动和涡旋萃取,离心后取下层有机相分析,外标法定量。该方法在25 mg/kg~1 000 mg/kg范围内线性良好,r2为0.997 2~0.999 0,回收率为95.6%~99.2%,相对标准偏差均小于4.0。对羟基苯甲酸甲酯、乙酯、丙酯和丁酯的定量下限为1.2 mg/kg~3.2 mg/kg。     

Application of Air-Assisted Liquid-Liquid Microextraction for Determination of Some Fluoroquinolones in Milk Powder and Egg Samples: Comparison with Conventional Dispersive Liquid-Liquid Microextraction

Herein, an air-assisted liquid-liquid microextraction (AALLME) has been described and compared to conventional dispersive liquid-liquid microextraction (DLLME) for the extraction/preconcentration of six fluoroquinolone compounds in milk powder and egg samples prior to high-performance liquid chromatography-UV detection (HPLC-UV). In order to compare the novel AALLME technique to the conventional DLLME technique, several parameters that influence the extraction efficiency were studied and optimized. Both methods have been validated for milk powder and egg analysis, obtaining limits of quantification lower than those usually permitted by legislation in food matrices, with precisions expressed as coefficients of variation lower than 8 % and recoveries between 72 and 115 % which were acceptable recoveries and repeatability. An AALLME method needs less organic solvent and shorter centrifugation time; therefore, it is more environmentally friendly and efficiently compared to DLLME.     

DLLME-UPLC-MS/MS法测定食用油中的双酚类化合物

基于分散液液微萃取(DLLME)技术和同位素稀释-超高效液相色谱-质谱/质谱(ID-UPLC-MS/MS),建立了一种快速测定食用油中7种双酚类化合物的方法。优化了萃取剂种类及体积、涡旋分散时间等影响萃取的关键因素;优化了UPLC分离条件和质谱定性定量参数。优化条件为:400μL甲醇/乙腈(1∶1,v/v)混合溶液作为萃取剂,涡旋分散萃取1 min;以C18色谱柱和甲醇-0.05%氨水梯度洗脱分离,质谱多反应监测模式(MRM)测定。结果表明,7种双酚类化合物在0.5μg/L~500μg/L内线性关系良好,相关系数均在大于0.998,方法定量限(S/N=10)在0.2μg/L~3.0μg/kg之间,3个添加水平的平均回收率为80.1%~93.7%,相对标准偏差(n=6)为4.4%~9.1%。本方法前处理简单,节省溶剂和时间,准确灵敏,适用于食用油中7种双酚类化合物的检测。     

顶空固相微萃取-气相色谱-质谱法检测茶叶中雪松醇

该文建立一种顶空固相微萃取（headspace solid-phase microextraction,HS-SPME）和气相色谱质谱（gas chromatography-mass spectrometry,GC-MS）联用的分析技术,用以检测茶叶香气成分雪松醇。通过优化HS-SPME萃取纤维、萃取温度、萃取时间及搅拌速度因素,确定最适宜HS-SPME条件：采用50/30 μm DVB/CAR/PDMS萃取涂层的萃取纤维,在萃取温度为80℃、转速为300 r/min下萃取30 min,雪松醇萃取和检测效果最好。此外,为评估该方法的萃取性能,对方法加标回收率、线性关系及实际茶叶样品进行分析,结果证实该方法灵敏度和重复性高。     

离子液体分散液-液微萃取-高效液相色谱法测定牛奶中己烯雌酚

建立离子液体分散液-液微萃取与高效液相色谱-紫外检测器相结合测定牛奶中己烯雌酚含量的方法。考察萃取溶剂、抗黏剂、pH值、离子强度及温度对萃取效率的影响。结果表明,该法对样品中己烯雌酚的萃取灵敏度高,检出限为0.5 μg/L,相对标准偏差在2.80%～4.43%之间,平均回收率为93.7%～103.2%。该技术可以满足牛奶中己烯雌酚含量的测定。     

猪肉中有机氯农药多组分的顶空固相微萃取-气相色谱-质谱检测技术初探

目的探讨建立顶空固相微萃取快速测定有机氯农药残留方法。方法以稳定性同位素13C6-六氯苯和13C10-灭蚁灵为内标,以顶空固相微萃取作为猪肉样品的前处理手段,采用气相色谱-质谱的选择离子模式(SIM)测定猪肉样品中18种有机氯农药组分。通过对萃取头类型、萃取时间、萃取温度、解析温度和时间、盐溶液的浓度等影响萃取效率的因素的研究,获得了优化的试验参数。结果在给定条件下,方法线性范围在1~100ng/kg范围内,混和标准溶液的加标回收率在90%~120%之间,相对标准偏差在3%~15%之间。结论本方法适合于猪肉样品中的有机氯农药多残留的快速检测,为农药残留的筛选提供了有效的监测手段。     

Dispersive-Solid-Phase Extraction Cleanup Integrated to Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Droplet for Determination of Organochlorine Pesticides in Vegetables

A simple and rapid method applying acetonitrile extraction, dispersive-solid-phase extraction (d-SPE) cleanup, and dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) was developed for determination of organochlorine pesticides in vegetables. In order to simplify operation, d-SPE cleanup was integrated to DLLME-SFO concentration procedure, and a protection device for glass tube was applied to achieving high-speed centrifugation. The comparison study between the integrated d-SPE and normal d-SPE showed that the former could shorten the sample preparation time without decrease of cleanup efficiency. Subsequently, the necessity of using a high-centrifugation speed (more than 8603 g) for complete separation of the d-SPE sorbents, water phase, and organic phase was confirmed through turbidity analysis. The recoveries of the proposed method ranged from 77.2 to 112.5%, and the relative standard deviations were less than 15%. The limits of detection were in the range of 0.45 ~ 1.33 μg kg^?1, while the limits of quantitation were from 1.35 to 3.99 μg kg^?1, respectively. Finally, the method was successfully applied to analyze real vegetable samples.     

顶空固相微萃取联合气相色谱-质谱检测葡萄酒中2,4,6-三氯苯甲醚

利用响应面法优化采用顶空固相微萃取联合气相色谱-质谱技术检测葡萄酒中2,4,6-三氯苯甲醚（2,4,6-trichloroanisole,TCA）。对萃取头进行了选择,并优化固相微萃取参数：样品体积、萃取温度、平衡时间和萃取时间等对TCA萃取效果的影响。结果表明,用聚二甲基硅氧烷/二乙烯基苯（65 μm）萃取头进行TCA萃取的最佳条件：样品9.8 mL、2 g NaCl、33 ℃平衡10 min、萃取90 min进行气相色谱-质谱分析,以TCA-d5为内标物进行定量。该方法的相关系数R2为0.999 9,重复性的相对标准偏差为1.03%,加标回收率范围在95.7%～106.1%之间,检出限和定量限分别为0.3 ng/L和1 ng/L。检测7 种市售葡萄酒产品的TCA含量在0～7.6 ng/L之间,干白葡萄酒中TCA含量低于干红葡萄酒。该方法操作简单、可靠,适用于葡萄酒中TCA的测定。     

Determination of Vanillin and Ethyl-Vanillin in Milk Powder by Headspace Solid-Phase Microextraction Coupled with Gas Chromatography-Mass Spectrometry

A method for determination of vanillin and ethyl-vanillin in milk powder by auto headspace solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was established. Vanillins in sample were extracted with SPME through a fused-silica fiber coated with divinylbenzene/polydimethylsiloxane. The analytes were desorbed by GC at 260 °C for 5 min and separated on a DB-5MS capillary column and detected by MS with EI source by selected ion monitoring mode (EI-SIM). As a result, the limit of detection of vanillin and ethyl-vanillin was 0.1 and 0.05 mg/kg. The spiked recovery was between 90.0 and 100 %, and the RSD ranged from 1.9 to 5.1 % (n?=?6). This method eliminated the interferences from complicated matrix effectively. The method was successfully applied for quick determination of vanillin and ethyl-vanillin content in milk powder samples.