HS-SPME–GC–MS法测定水中2-甲基异冰片及土臭素

采用顶空固相微萃取–气质联用(HS-SPME–GC–MS)的方法对地表水中2-甲基异冰片(2-MIB)和土臭素(GSM)进行分析测定。通过试验确定了HS-SPME的最佳萃取条件:萃取头为DVB/CAR/PDMS,萃取时间为30 min,萃取温度为70℃,NaCl的加入量为30%(质量分数),萃取纤维在GC上的解吸温度为250℃。用内标法进行定量,2-MIB,GSM的质量浓度在5~100 ng/L范围内与色谱峰面积呈良好的线性关系,线性相关系数(r2)分别为0.999 7,0.997 0,检出限分别为0.8,1.7 ng/L。采用该法对水样进行测定,2-MIB,GSM测定结果的相对标准偏差为2.6%~6.3%(n=6),加标回收率为92%~112%。该方法能简单、快速地测定水中痕量嗅味物质。     

顶空液相微萃取/气相色谱-质谱对中药枳壳中有机挥发物的快速分析

建立了顶空液相微萃取/气相色谱-质谱联用测定中药枳壳中有机挥发物的方法.在顶空液相微萃取实验条件优化的基础上,确定了最佳实验条件:以正辛烷作为有机萃取剂,体积为2 μL,样品用量为0.3 g,液滴距离样品表面0.8 cm处,萃取8 min后直接进样.与固相微萃取/气相色谱-质谱法相比,顶空液相微萃取法定性了30种成分,固相微萃取法定性了24种成分,顶空液相微萃取法操作简单、快速,实验结果灵敏度更高,且萃取效率高,重复性好,可用于中药枳壳中有机挥发物的快速分析.     

固相微萃取-气相色谱-质谱法测定饮用水源中53种挥发性有机污染物

应用固相微萃取-气相色谱-质谱法测定饮用水源中53种挥发性有机污染物的含量。优化的试验条件如下:1萃取纤维为DVB/CAR/PDMS;2萃取温度为25℃;3顶空体积为9mL;4萃取时间为10min;5解吸温度为200℃;6解吸时间为3min。在气相色谱分离中用VF-624MS柱为固定相,在质谱分析中采用全扫描模式。53种挥发性有机污染物在一定的质量浓度范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.001~0.130μg·L-1之间。方法用于实际水样的分析,加标回收率在75.9%~107%之间,测定值的相对标准偏差(n=5)在0.5%~18%之间。     

顶空固相微萃取-气相色谱法测定卷烟包装材料中残留溶剂

提出了顶空固相微萃取-气相色谱法测定卷烟包装材料中常用溶剂的方法。为使固相微萃取达到更高的效率,选用75μm CAR/PDMS的固相微萃取头,萃取温度及时间为100℃和40min,解吸温度及时间为200℃和10min。用DB-1石英毛细管色谱柱分离,火焰离子化检测器检测。方法的加标回收率在79%～92%之间,相对标准偏...     

顶空固相微萃取-气相色谱-质谱法测定食用植物油中挥发性有机物

提出了顶空固相微萃取-气相色谱-质谱法测定食用植物油中35种挥发性有机物(VOC′s)含量的方法。为使固相微萃取达到更高的效率,选用75μm碳分子筛-聚二甲基硅氧烷纤维作为微萃取的涂层,萃取温度及时间为90℃和30 min。用DB-5MS毛细管色谱柱分离,电子轰击离子源全扫描监测模式检测。35种VOC′s在一定的质量浓度范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.03~6.84μg·L-1之间。在3个添加水平上做回收试验,加标回收率在91.0%~108.3%之间,相对标准偏差(n=5)小于10%。     

固相微萃取-气相色谱-质谱法同时测定天然饮用水中39种有机污染物

提出了固相微萃取-气相色谱-质谱法测定天然饮用水中39种有机污染物含量的方法。为使固相微萃取达到更高的效率,选用60μm PDMS/DVB作为固相萃取头的涂层,萃取温度及时间为90℃和30min,解析温度及时间为270℃和10min。用J&W DB-35 MS毛细管色谱柱分离,电子轰击离子源选择离子监测模式检测。39种有机污染物的质量浓度均在0.10～50.0μg.L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.002～2μg.L-1之间。方法的回收率在82.0%～110%之间,测定值的相对标准偏差(n=6)在2.0%～13%之间。     

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。     

顶空固相微萃取-气相色谱-质谱法用于白术中挥发性成分的分析

采用顶空固相微萃取-气相色谱-质谱法(HS-SPME-GC-MS)分离鉴定了白术中的挥发性成分,并与采用传统的水蒸气蒸馏法(SD)提取的挥发性成分进行了比较。实验中筛选了固相微萃取纤维头,优化了SPME的操作条件。样品在70 ℃下平衡30 min后,用65 μm聚二甲基硅氧烷-二乙烯基苯(PDMS-DVB)纤维头对白术样品顶空吸附30 min,于250 ℃下解吸4 min, 然后采用GC-MS对解吸物进行分离鉴定;采用HS-SPME-GC-MS鉴定出41种组分,占总峰面积的90.81%;采用SD-GC-MS鉴定出31个组分,占总峰面积的88.19%,且采用SD所提取的组分基本上都被固相微萃取所提取。结果表明, HS-SPME可取代耗时的SD用于白术中挥发性物质的提取。     

微孔有机聚合物固相微萃取纤维的制备及在有机氯农药检测中的应用

利用1,3,6,8-四(4-醛基)芘和三聚氰胺为单体合成微孔有机聚合物(MOP),并将其固定在不锈钢丝上,制备成固相微萃取纤维涂层。将其用于顶空固相微萃取(HS-SPME),结合气相色谱-电子捕获检测手段,建立了对大米中有机氯农药的在线检测方法。实验考察了4种实验参数对富集能力的影响,得到了最优的实验条件:萃取温度80℃、萃取时间25 min、NaCl质量浓度200 g/L、解吸时间6 min。在此实验条件下,对有机氯农药的富集倍数达到115~318倍。方法在0.05~50μg/kg范围内具有良好的线性关系,检出限为2.4~11.3 ng/kg。同一纤维及不同纤维富集后测定结果的相对标准偏差范围分别为1.3%~13.1%和2.3%~13.6%。该方法简单、快速,可以实现对实际样品中有机氯农药的痕量分析。     

自制离子液体固相微萃取涂层分析人体尿液中的五氯酚

建立了顶空固相微萃取与气相色谱法（HS-SPME-GC）测定人体尿液中五氯酚（PCP）的新方法。 采用溶胶-凝胶法,加入自制的离子液体键合固相微萃取涂层,优化了萃取温度、萃取时间、pH值、离子强度及解吸时间。 结果表明,样品中加入3 g NaCl,溶液的pH值为2,并以一定速度搅拌的条件下,在80 ℃顶空萃取50 min,300 ℃下解吸5 min,方法的检测限为5.0 ng/L,线性范围为0.05～100 μg/L,相对标准偏差(RSD)为5.9%,加标回收率为106.6%。     

顶空气相色谱法测定化妆品中15种挥发性有机溶剂残留

建立了化妆品中15种挥发性有机溶剂残留的顶空气相色谱测定方法。样品经60 ℃、30 min静态顶空后,采用气相色谱-氢火焰离子化检测器进行检测,外标法定量。加标回收试验结果表明: 15种挥发性有机溶剂残留平均回收率为62.8%～116%,相对标准偏差均小于5%。方法的检出限为0.09～0.68 mg/kg。该方法可有效克服基体干扰,一次进样可同时分离和测定化妆品中15种挥发性有机溶剂,准确灵敏,简单快速,适用于化妆品中挥发性有机溶剂残留的检测。     

热解吸–气质联用法测定纺织品中有机挥发物的含量

采用热解吸–气质联用法测定纺织品中有机挥发物氯乙烯、1,3-丁二烯、甲苯、4-乙烯基环己烯、苯乙烯、4-苯基环己烯的含量。吹扫载气N2流量为30 m L/min,100℃吹扫顶空腔30 min,然后于290℃解吸吸附管10 min。色谱柱为DB–624柱,初始柱温35℃,保持5 min,以10℃/min升至240℃,保持10 min。检测上述6种有机物的线性范围分别为21.13~426.26,21.12~422.49,4.22~211.00,4.10~204.85,2.10~209.70,4.43~221.30μg/m L,线性相关系数均大于0.99。3个添加水平的平均回收率为88.8%~110.2%,测定结果的相对标准偏差为1.95%~6.59%(n=4)。该方法重现性好,测量结果准确,可作为纺织品质量控制的参考方法。     

固相微萃取-气相色谱/同位素质谱法测定水中挥发性有机物单体碳同位素

建立了采用75μm碳分子筛/聚二甲基硅氧烷(CAR-PDMS)纤维的固相微萃取-气相色谱/同位素质谱联用方法测定水中挥发性有机污染物碳同位素。使用浸入式固相微萃取和顶空固相微萃取方法进行实验确定在低浓度条件下最佳δ13C测试方法。通过使用顶空固相微萃取前处理技术进行单体同位素分析分析灵敏度更高,应用CSIA技术对1,2-二氯乙烯,三氯乙烯,四氯化碳进行单体同位素分析,方法的检出限为70μg/L,与样本的标准偏差小于0.3‰。该法适用于水体中微量挥发性有机污染物的同位素组成测定。     

顶空–气相色谱/质谱法测定餐垫纸中16种挥发性有机物残留

采用顶空–气相色谱/质谱法同时测定餐垫纸中16种挥发性有机化合物(无水乙醇、异丙醇、正丁醇、丙酮、丁酮、己醛乙酸乙酯、乙酸异丙酯、乙酸丁酯、丙二醇甲醚、乙酸正丙酯、苯、甲苯、间二甲苯、对二甲苯、邻二甲苯)的含量。采用恒流模式,流速设定为2.5 mL/min,程序升温,16种挥发性有机化合物可以很好地分离。各成分工作曲线的相关系数r2均大于0.999 5,加标回收率在86.6%~104.8%之间,测定结果的相对标准偏差均不大于6.9%(n=6);各成分的检出限均低于0.01 mg/m2。该法具有进样简单,分离效果好,精密度高等特点,能够满足餐垫纸中挥发性有机物检测要求。     

电子鼻测定植物挥发性有机物方法研究

建立了电子鼻技术(GC/SAW)快速实时检测植物挥发性有机物(BVOCS)的分析方法。考察了检测器温度、进样温度、柱温、升温速率等因素的影响,确定了电子鼻技术分析BVOCS的最佳条件为:检测器温度60℃、进样口温度100℃、柱温40～145℃(10℃/s)、阀温145℃、预浓缩管250℃、载气流速3mL/min。在上述条件下,测得不同时间(日内、日间)α-蒎烯和异戊二烯分别在0.027～8.580mg·L-1、0.425～68.100mg·L-1范围内线性良好;α-蒎烯和异戊二烯的回收率分别在90.74%～107.41%和91.29%～102.88%之间;相对标准偏差(RSD)均小于5%;检测限在0.2～1.0μg·L-1内。     

Analysis of volatile organic compounds in pleural effusions by headspace solid‐phase microextraction coupled with cryotrap gas chromatography and mass spectrometry

Headspace solid‐phase microextraction coupled with cryotrap gas chromatography and mass spectrometry was applied to the analysis of volatile organic compounds in pleural effusions. The highly volatile organic compounds were separated successfully with high sensitivity by the employment of a cryotrap device, with the construction of a cold column head by freezing a segment of metal capillary with liquid nitrogen. A total of 76 volatile organic compounds were identified in 50 pleural effusion samples (20 malignant effusions and 30 benign effusions). Among them, 34 more volatile organic compounds were detected with the retention time less than 8 min, by comparing with the normal headspace solid‐phase microextraction coupled with gas chromatography and mass spectrometry method. Furthermore, 24 volatile organic compounds with high occurrence frequency in pleural effusion samples, 18 of which with the retention time less than 8 min, were selected for the comparative analysis. The results of average peak area comparison and box‐plot analysis showed that except for cyclohexanone, 2‐ethyl‐1‐hexanol, and tetramethylbenzene, which have been reported as potential cancer biomarkers, cyclohexanol, dichloromethane, ethyl acetate, n‐heptane, ethylbenzene, and xylene also had differential expression between malignant and benign effusions. Therefore, the proposed approach was valuable for the comprehensive characterization of volatile organic compounds in pleural effusions.     

Polybutylene terephthalate-nickel oxide nanocomposite as a fiber coating

A highly efficient polybutylene terephthalate (PBT)-based nanocomposite containing nickel oxide nanoparticles was synthesized by electrospinning technique and used as a fiber coating for solid phase microextraction. The influential morphological parameters and capability of the prepared nanocomposite including the NiO content, the coating time, the PBT concentration and applied voltage were considered for optimization. The applicability of the synthesized fiber coating was examined by headspace solid phase micro extraction and gas chromatography mass spectrometry detection of some volatile organic compounds in aqueous samples. Among the synthesized nanocomposites and pristine PBT nanofibers, the fiber coating with 14% of NiO nanoparticles doping level exhibited the highest extraction efficiency. In addition, important parameters influencing the extraction/desorption process were investigated and optimized. The detection limits were less than 5 ng L⁻¹ using the selected ion monitoring mode. The inter-day and intra-day precisions of the developed method under optimized conditions were below 11%. The method showed a linearity in the range of 10–1000 ng L⁻¹ with the correlation coefficient greater than 0.9987. The optimized method was applied to the sampling of some volatile organic compounds from real water samples. The developed method is convenient, rapid, simple, easy and inexpensive and offers high sensitivity and sufficient reproducibility.     

化妆品中挥发性有机溶剂的通用检测方法

以化妆品配方中常见及禁用的36种有机溶剂为研究模板,建立了化妆品中挥发性有机溶剂残留评价初筛知识库、确证知识库和定量方法。初筛知识库包括双柱保留指数知识库和NIST质谱库。双柱保留指数知识库以保留指数为定性指标,选择极性的VF-1301ms和非极性的DB-5ms两根色谱柱,用顶空气相色谱-质谱法考察了36种有机溶剂在两种色谱分离系统中的保留特性。利用NIST MS search 2.0作为检索工具,同时建立了36种挥发性有机溶剂的顶空气相色谱-质谱定量方法。样品经60 ℃、30 min静态顶空后以连接了VF-1301ms石英毛细管色谱柱的气相色谱-质谱仪检测,外标法定量。方法检出限为0.01~3.3 μg/g,加标回收率为60.77%~126.60%。该方法从通用性的角度,为化妆品中挥发性有机溶剂残留的筛查、鉴别和定量提供方法,部分解决了测定化妆品中挥发性有机溶剂时需要针对不同检测目标建立不同方法以及潜在溶剂存在备选筛查的问题。     

荧光衍生化-磁分散固相萃取/高效液相色谱检测池塘水与蔬菜中3种挥发性异味物质

以6-碳酰氯左氧氟沙星(LFC-Cl)为衍生试剂,磁性氧化石墨烯(MGO)为吸附剂,建立了2-甲基异莰醇(2-MIB)、土臭素(GSM)和3-甲基-1-丁醇(3-MB)的高效液相色谱荧光检测(HPLC-FLD)分析方法。在浓度为0.05 mol/L的4-二甲氨基吡啶(DMAP)乙腈溶液中,衍生温度60℃,反应时间90 min,超声波辅助条件下,可完成上述3种醇类挥发性异味物质(VOCs)的衍生化。在吸附剂用量20 mg、萃取时间20 min、解吸剂为乙腈(含1%甲酸)、解吸时间3 min条件下,能实现3种异味物质衍生物的富集和净化。在优化的HPLC条件下,15 min内可实现3种衍生物的基线分离和高灵敏检测。方法检出限(LOD)为0.020~0.95 ng/L,定量下限(LOQ)为0.10~3.3 ng/L,线性、精密度和回收率良好。与已报道的方法相比,该方法具有灵敏度高、样品前处理简单、仪器普适性好等优势,可用于池塘水、蔬菜中VOCs的快速、定量测定,为食品和环境水样监测提供了一种新方法。     

Sampling volatile organic compounds using a modified solid phase microextraction device

Headspace solid phase microextraction (headspace SPME) has been demonstrated to be an excellent solvent-free sampling method. One of the major factors contributing to the success of headspace SPME is the concentrating effect of the fiber coating toward organic compounds. The affinity of the fiber coating toward very volatile analytes, such as chloromethane, may, however, not be large enough for detection at the parts per trillion concentration level. Static headspace analysis, on the other hand, is very effective for these very volatile compounds. As analyte volatility decreases, the sensitivity of static headspace analysis drops. The complementary nature of these two sampling methods can be exploited by combining the SPME device with a gastight syringe. The sensitivity of the new sampling device is better than that of SPME for very volatile compounds or that of static headspace analysis for less volatile compounds. This new method can sample a wide range of compounds from chloromethane (b.p. −24°C) to bromoform (b.p. 149°C) with estimated limits of detection at the low parts per trillion level.