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1.
应用搅拌棒吸附萃取富集及热解吸进样与气相色谱-质谱相结合测定了水样中3种烷基酚(即正辛基酚、叔辛基酚和正壬基酚)的含量。将水样预先用盐酸调节其酸度至pH 3,分取10.00mL置于顶空瓶中,放入搅拌棒进行吸附萃取。取出搅拌棒,置于热脱附管上解吸并通过程序升温进样系统进样,用DB-5MS柱进行色谱分离。质谱分析条件:电子轰击正离子源,全扫描模式(定性分析)和选择离子扫描模式(定量分析)。3种烷基酚的质量浓度均在5~200ng·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在1.2~2.5ng·L-1之间。以实际水样为基体进行加标回收试验,测得回收率在95.0%~118%之间,测定值的相对标准偏差(n=5)在0.90%~10%之间。  相似文献   

2.
地表水中微量三氟乙酸的分析方法   总被引:2,自引:0,他引:2  
张剑波  胡建信  曾铮  朱燕 《分析化学》2005,33(4):549-552
研究了测定表面水体样品中微量三氟乙酸(TFA)浓度的分析方法,将样品中的三氟乙酸与硫酸二甲酯(DMS)在浓硫酸介质,温度80℃下衍生为三氟乙酸甲酯(MTFA),利用MTFA的易挥发性,50℃下顶空进样,并用气相色谱一质谱联用的方法检测样品中MTFA的浓度,进而得到环境水样中TFA的浓度。方法的检出限为3.0μg/L。样品的加标回收率在84%~92%。应用此方法测定北京部分地表水样中的三氟乙酸浓度分别为43~107ng/L。  相似文献   

3.
提出用顶空采样法富集水样中12种氯代苯胺类化合物,经气相色谱分离后用质谱法测定其含量。试验选择了最佳顶空条件。取水样8.00mL置于顶空瓶中,加入碳酸钠3.4g(盐析剂)和0.500mg·L-1内标溶液8μL,于80℃恒温条件下振荡40min。测定的12种化合物以气体状态进入DB-35MS色谱柱,按程序升温模式进行分离;质谱测定中,采用电子轰击离子源和选择离子监测模式。12种氯代苯胺类化合物的质量浓度在一定范围内与其峰面积呈线性关系,其检出限(3.14s)在0.03~0.3μg·L-1之间。按标准加入法进行回收试验,测得回收率在86.0%~131%之间,测定值的相对标准偏差(n=6)在3.0%~20%之间。  相似文献   

4.
专利     
《化学分析计量》2014,(1):47-47
一种测定塞来昔布中三氟乙酸残留量的方法 摘要 本发明公开了一种测定塞来昔布中三氟乙酸残留量的方法。采用气相色谱法,选用毛细管柱,ECD为检测器,以硫酸–甲醇、硫酸二甲酯、碘甲烷为甲酯化试剂,将三氟乙酸通过甲酯化生成合适顶空进样的三氟乙酸甲酯,与现有技术相比,本方法可以用于塞来昔布中三氟乙酸含量的测定。  相似文献   

5.
<正>公开号:CN103439427A公开日:2013.12.11申请人:江苏正大清江制药有限公司摘要本发明公开了一种测定塞来昔布中三氟乙酸残留量的方法。采用气相色谱法,选用毛细管柱,ECD为检测器,以硫酸–甲醇、硫酸二甲酯、碘甲烷为甲酯化试剂,将三氟乙酸通过甲酯化生成合适顶空进样的三氟乙酸甲酯,与现有技术相比,本方法可以用于塞来昔布中三氟乙酸含量的测定。  相似文献   

6.
取样品0.100 0g用5.0mL水超声溶解,并引入顶空进样仪中,在80℃下加热30min达到平衡。对溶液中甲醇经顶空提取后,以HP-INNOWAX毛细管色谱柱为固定相进行气相色谱分离。质谱分析中采用选择离子监测模式,外标法定量。甲醇的质量浓度在0.50~100mg·L~(-1)内与其峰面积呈线性关系,检出限(3S/N)为0.002 5%。按标准加入法进行回收试验,测得回收率在90.0%~100%之间,测定值的相对标准偏差(n=6)均小于2.2%。  相似文献   

7.
基于离子液体无蒸气压、高沸点、溶解能力优良及混合离子液体同时具有亲水和疏水性的特点,建立了以[Bmim]PF6∶[Bmim]BF4为1∶2的混合离子液体作为顶空溶剂,平衡加压静态顶空进样测定转基因大豆油中六六六、滴滴涕残留量的方法。对离子液体的种类、配比、用量,以及顶空平衡温度、顶空平衡时间、顶空进样时间等条件进行了优化。研究结果表明:在最佳条件下,方法的线性范围为5~100 μg/L,相关系数为0.990 5~0.999 6,检出限为1.4~15.2 μg/kg,定量下限为4.7~48.6 μg/kg,回收率为72.3%~104.1 %,相对标准偏差为0.6%~7.8%。本方法快速、准确,且避免了复杂的前处理,是顶空进样检测农残的新方法。  相似文献   

8.
基于离子液体无蒸气压、高沸点、溶解能力优良及混合离子液体同时具有亲水和疏水性的特点,建立了以[Bmim]PF6∶[Bmim]BF4为1∶2的混合离子液体作为顶空溶剂,平衡加压静态顶空进样测定转基因大豆油中六六六、滴滴涕残留量的方法。对离子液体的种类、配比、用量,以及顶空平衡温度、顶空平衡时间、顶空进样时间等条件进行了优化。研究结果表明:在最佳条件下,方法的线性范围为5~100μg/L,相关系数为0.990 5~0.999 6,检出限为1.4~15.2μg/kg,定量下限为4.7~48.6μg/kg,回收率为72.3%~104.1%,相对标准偏差为0.6%~7.8%。本方法快速、准确,且避免了复杂的前处理,是顶空进样检测农残的新方法。  相似文献   

9.
顶空进样-气相色谱法检测乳制品中硫氰酸盐的含量   总被引:2,自引:0,他引:2  
建立了顶空进样气相色谱法测定乳制品中硫氰酸盐含量的方法。乳制品中硫氰酸盐用水提取,然后用乙酸锌溶液沉淀蛋白质,将提取液离心,取上清液加入氯胺T将硫氰酸离子衍生为氯化氰,顶空进样,经BP10(14%氰丙基苯基聚硅氧烷)气相色谱柱分离,电子捕获检测器(ECD)检测,外标法定量,同时对衍生剂用量、顶空加热时间和保温温度进行了优化。结果表明: 硫氰酸盐在0.005~0.1 mg/L内线性关系良好,相关系数(r)为0.997,定量限(以信噪比(S/N)≥10计)为0.1 mg/kg。在1.0、2.0、10.0 mg/kg 3个添加水平下进行了回收率和精密度试验,加标回收率为90.0%~110.0%,相对标准偏差(RSD, n=10)为4.98%~7.89%。该方法操作简便、快速、稳定性好,可用于乳制品中硫氰酸盐的测定,能满足日常检测要求。应用该法对市售的18种乳制品进行了检测,发现所测乳制品皆含有硫氰酸盐,含量大约在0.5~10 mg/kg。  相似文献   

10.
提出了顶空-气相色谱-质谱法测定丙烯腈-丁二烯-苯乙烯(ABS)玩具中丙烯腈单体的含量。样品经N,N-二甲基甲酰胺溶解,在顶空进样器恒温进样,采用HP-INNO Wax极性柱进行分离,质谱中以m/z53作为目标离子,外标法进行定量。丙烯腈单体的质量在1.00~40.0μg的范围内线性良好,检出限(3S/N)为0.4mg·kg-1。方法应用于ABS玩具样品的分析,加标回收率在78.0%~116%之间,测定值的相对标准偏差(n=6)在2.6%~7.9%之间。  相似文献   

11.
采用顶空气相色谱法间接测定了羧甲基壳聚糖中氯乙酸的残留量。样品(0.2g)于顶空瓶中超声溶解在水3mL中,加入甲醇2.5mL,硫酸1.5mL,在70℃水浴反应40min使之酯化。按顶空条件进样,用HP-INNOWAX毛细管色谱柱分离,氢火焰离子化检测器测定。分别选择15min和85℃作为样品在顶空瓶中的平衡时间和平衡温度。氯乙酸的质量在0.2~20mg范围内与其峰面积呈线性关系,方法的检出限(3S/N)为5.6mg·L-1。方法用于实样中氯乙酸的测定,用标准加入法做回收试验,测得回收率在90.0%~92.0%之间,测定值的相对标准偏差(n=5)在0.7%~0.9%之间。  相似文献   

12.
Selected ion flow tube mass spectrometry (SIFT-MS) is a technique that is well suited to the real-time analysis of head-space. SIFT-MS gives a non-discriminatory snapshot of the volatiles present and their amounts, and is considered to display less bias than chromatographic techniques as neither sample pre-treatment nor separation are necessary in most cases. The technique has been used for analysis of virgin olive oil head-space on more than 100 different oils. Twenty of these are reported. The results obtained using this technique differ from those normally reported from chromatographic analyses in that the dominant species in the head-space of all oils tested were methanol and ethanol. These volatiles were present in the head-space in the concentration ranges of 2.8-11.3 ppm (methanol) and 0.4-4.9 ppm (ethanol). (E)-2-Hexenal, normally reported as the dominant olive oil volatile, is found in significantly lower concentrations and is in the range of 0.02-1.6 ppm.  相似文献   

13.
A new and simple method for the determination of hydroxylamine in environmental water, such as fresh rivers and lakes using hypochlorite, followed by its gas choromatographic detection, has been developed. A glass vial filled with sample water was sealed by a butyl-rubber stopper and aluminum cap without head-space, and then sodium hypochlorite solution was injected into the vial through a syringe to convert hydroxylamine to nitrous oxide. The head-space in the glass vial was prepared with 99.9% grade N2 using a gas-tight syringe. After the glass vial was shaken for a few minutes, nitrous oxide in the gas-phase was measured by a gas chromatograph with an electron-capture detector. The dissolved nitrous oxide in the liquid-phase was calculated according to the solubility formula. The proposed method was applied to the analysis of fresh-water samples taken from Iu river and Hii river, flowing into brackish Lakes Nakaumi and Shinji, respectively.  相似文献   

14.
As equilibration for head-space analysis of solid polymers is too slow a polymer solution is used. Detection limit of styrene is 10 mg/kg of polystyrene. Using the automatic head-space analysator F 40 combined with computerised data processing human operation time per sample is reduced to 6 min.  相似文献   

15.
A fast head-space analysis instrument, constituted by an automatic sample introduction system directly coupled to a mass detector without performing any chromatographic separation, was assembled. A suitable and original response was computed to optimise, by experimental design, the measured signals for discrimination purposes. The volatile fractions of 105 extra virgin olive oils coming from five different Mediterranean areas were analysed. The rough information collected by this system was unravelled and explained by well-known chemometrical techniques of display (principal component analysis), feature selection (stepwise linear discriminant analysis) and classification (linear discriminant analysis). The 93.4% of samples resulted to be correctly classified and the 90.5% correctly predicted by cross-validation procedure, whilst the 80.0% of an external test set, created to full validate the classification rule, were correctly assigned.  相似文献   

16.
Kaljurand  M.  Smit  H. C. 《Chromatographia》1994,39(3-4):210-215
Summary Gas chromatography has been used to study the kinetics of evolution of volatiles from polypropylene samples (at 70°C). Correlation chromatography (CC) and the trapping of volatiles on Tenax sorbents and activated charcoal were employed to improve the detector signal. As a reference, the kinetics of gas evolution was studied by making a series of direct single injections of polymer head-space gas on a GC column. The results of trapping differed from those obtained by single injection. However, the data from single injections and CC were in good agreement. The CC method was found to offer far more operator convenience for dynamic head-space analysis than sample trapping, being less subject to operator errors.  相似文献   

17.
A method was optimized for the analysis of omeprazole (OMZ) by ultra-high speed LC with diode array detection using a monolithic Chromolith Fast Gradient RP 18 endcapped column (50 x 2.0 mm id). The analyses were performed at 30 degrees C using a mobile phase consisting of 0.15% (v/v) trifluoroacetic acid (TFA) in water (solvent A) and 0.15% (v/v) TFA in acetonitrile (solvent B) under a linear gradient of 5 to 90% B in 1 min at a flow rate of 1.0 mL/min and detection at 220 nm. Under these conditions, OMZ retention time was approximately 0.74 min. Validation parameters, such as selectivity, linearity, precision, accuracy, and robustness, showed results within the acceptable criteria. The method developed was successfully applied to OMZ enteric-coated pellets, showing that this assay can be used in the pharmaceutical industry for routine QC analysis. Moreover, the analytical conditions established allow for the simultaneous analysis of OMZ metabolites, 5-hydroxyomeprazole and omeprazole sulfone, in the same run, showing that this method can be extended to other matrixes with adequate procedures for sample preparation.  相似文献   

18.
Trifluoroacetate (TFA) is commonly used in a variety of pharmaceutical applications. Because of its toxic nature, it is important to reliably measure the effective removal of TFA. We developed an ion chromatography (IC) method to determine the concentration of residual TFA in samples found in the pharmaceutical industry. A high-capacity anion-exchange column was used to separate trace trifluoroacetate from an excess of chloride, phosphate, and other anions without the need for sample preparation. TFA was detected by suppressed conductivity. A method with four KOH eluent step changes was optimized and reproducibly executed using automated generation of the KOH eluent. We used this method to determine TFA in the following samples: a phosphate-buffered saline (PBS), an acetate-buffered saline containing protein, and a commercial peptide. The method detection limits for TFA in these samples were all less than 90 ng/ml.  相似文献   

19.
采用顶空固相微萃取-气相色谱-质谱法对饮用水源水中1,3,5-三氯苯进行了测定。以1,2-二氯苯-d4为内标,用PDMS萃取头顶空萃取20min,萃取头于气相色谱进样口解析5min。采用DB-624色谱柱在程序升温条件下进行分离,质谱分析中采用电子轰击离子源(230℃,70eV)及选择离子监测模式测定。结果表明:1,3,5-三氯苯在0.100~2.50μg.L-1范围内呈线性,检出限(3S/N)为0.019μg.L-1。方法用于河流及水库水中的1,3,5-三氯苯的测定,加标回收率在91.5%~126.0%之间。  相似文献   

20.
As part of the formulation of a cell-based pharmaceutical product, cells were harvested from mice and incubated in a cocktail containing cell culture media and high levels of trifluoroacetic acid (TFA). The cells were washed with a phosphate-buffered saline solution to remove residual cell culture media and other reagents before the cells were infused back into the mice from which they originated. Because of the potentially toxic nature of the TFA, the cells were washed multiple times and the final wash was monitored for residual TFA in order to demonstrate the efficient removal of the reagent before the cell product could be reintroduced into the test animal. This report describes the method that was developed incorporating anion-exchange chromatography with suppressed conductivity detection for the analysis of residual TFA (down to 50 ng/ml) in the presence of high concentrations of phosphate and chloride interferences. The ultimate sensitivity of the method was improved by selectively removing halide anions using a silver cartridge before sample analysis. The method proved to be rugged and reproducible enough to be validated and used to monitor residual TFA levels in cell washes in support of an acute toxicological study. Results demonstrating the method’s sensitivity, selectivity, precision and linearity were reported.  相似文献   

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