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1.
为考察柱色谱分离和索氏提取两种固体样品提取方法对提取物组成的影响,探索操作条件温和、溶剂使用量经济的固体样品提取方法。本研究以吡啶为溶剂,对准葛尔黑岱沟、平朔、潞安常村3种不同变质程度的煤样进行了柱色谱分离和索氏抽提。提取物用凝胶色谱、电喷雾质谱和同步荧光光谱进行分析,比较和确定不同提取方法对煤提取物中组分分子量分布和结构的影响。分析发现,柱色谱分离与索氏提取相比,抽提率略有增加,但柱色谱提取物组分中缺失了提取样品中结构稳定的超大分子结构片断;质谱结果显示柱色谱抽提物中主要存在5个组分,提取物组分相对于索氏提取物单一、富集度高;同步荧光显示柱色谱提取物中芳香化合物的基本组成为3~5个环的芳香化合物。实验结果表明:如仅分析质量数小于1000 amu的化合物,柱色谱法可替代索氏提取法。  相似文献   

2.
气相色谱和气相色谱-质谱法测定食品中乙草胺残留   总被引:3,自引:0,他引:3  
建立了气相色谱和气相色谱-质谱法检测10种植物源性和动物源性食品中乙草胺残留量检测方法.粮谷类和动物源性样品采用乙腈提取,GPC结合硅胶固相萃取柱净化;蔬菜类样品采用乙酸乙酯提取、硅胶固相萃取柱净化;元葱等样品先进行微波消解,然后采用乙酸乙酯提取,硅胶固相萃取柱净化.气相色谱和气相色谱-质谱联用法检测.两种方法检出限均为0.004 mg/kg; 在0.01~0.16 mg/L范围内均呈良好的线性关系,相关系数为0.9998和0.9997;在0.01、0.02和0.05 mg/kg的添加水平下,添加回收率在70%~102%之间;相对标准偏差(RSD)均小于10%.  相似文献   

3.
Tong L  Yang J  Wu S 《色谱》2011,29(3):228-233
根据植物样品中的主要干扰物质,建立了用于气相色谱(GC)和气相色谱-质谱联用(GC-MS)测定植物样品中含氯有机污染物残留的样品前处理方法,有效提高了对植物样品中有机氯农药及多氯联苯检测的灵敏度。采用均质提取法对样品进行提取,考察了凝胶渗透色谱(GPC)和固相萃取(SPE)对提取液的净化效果。结果发现,采用GC测定目标物时,提取液需经GPC和SPE两次净化;而采用GC-MS测定目标物时,仅用SPE一次净化即可。该方法快速、经济、灵敏,适合多种植物样品中有机污染物残留分析的样品前处理要求。  相似文献   

4.
介绍了玩具样品中致敏芳香剂检测的前处理方式,包括振荡溶剂萃取、超声辅助溶剂提取、超临界流体萃取、热解吸和溶解沉淀技术,并综述了检测方法,包括气相色谱、气相色谱-质谱联用、高效液相色谱、高效液相色谱-质谱联用以及气相色谱-傅里叶变换红外光谱法,分析了现有检测方法的不足及存在的问题,展望了未来的研究方向。  相似文献   

5.
薄层色谱-荧光法测定黄连生物碱分配系数   总被引:2,自引:0,他引:2  
建立了薄层色谱和荧光分析法测定黄连生物碱在高速逆流色谱溶剂体系中分配系数的方法.样品在溶剂体系中分配平衡后,取等量的上下相,经点板、展开、刮板,提取后用荧光分光光度法检测样品的荧光值(激发波长365 nm,发射波长409 nm),并计算样品在溶剂体系中的分配系数.在一定的浓度范围内,4种生物碱的含量与荧光强度呈良好的线...  相似文献   

6.
分别采用溶剂回流提取和超声提取两种方法对灯盏花样品中的槲皮素进行提取,优化了提取条件,并用高效液相色谱进行了定量分析,采用扫描电镜分析了提取样品的表面形貌.结果表明:两种方法的提取率分别为0.048 7mg/g和0.042 3mg/g,溶剂回流的提取效果略优于超声提取;回流提取时的高温有利于提取物的溶出,而超声提取节能、快速.与此同时,采用两种方法提取的样品表面都受到明显的侵蚀,且回流提取时的机械搅拌促进样品的破碎,这些都有利于槲皮素的溶出.  相似文献   

7.
气相色谱-质谱法测定植物源性食品中残留的联苯菊酯   总被引:4,自引:0,他引:4  
建立了气相色谱-质谱检测8种植物源性食品中联苯菊酯残留量的方法。粮谷类样品采用乙腈提取、凝胶渗透色谱(GPC)结合Florisil固相萃取柱净化;蔬菜类样品采用乙酸乙酯提取、Florisil固相萃取柱净化,然后采用气相色谱-质谱测定,选择离子监测模式检测。方法的检出限为5 μg/kg(S/N=10);在0.005~0.5 mg/L范围内呈现良好的线性关系,相关系数为0.9999;在0.005,0.04和0.1 mg/kg 3个添加水平下,联苯菊酯的添加回收率在74%~99%之间,相对标准偏差(RSD)小于13%。该方法灵敏度高,净化效果良好,能有效地消除复杂基质带来的干扰,可以作为日常样品中联苯菊酯残留量的检测和确证方法。  相似文献   

8.
利用加速溶剂萃取/气相色谱-质谱联用法建立了同时测定土壤、沉积物和污泥中10种紫外线吸收剂的分析方法。样品采用加速溶剂萃取法提取,提取过程中加入硅胶进行同步净化,提取温度为120℃,提取溶剂为甲醇/二氯甲烷混合溶剂(V/V,50/50),静态循环2次,最后采用气相色谱-质谱联用仪分析检测。10种目标化合物的回收率为70.9%~117%,在土壤和沉积物样品中,大部分目标化合物的LOD<1 ng/g,LOQ<4 ng/g;污泥样品中,大部分目标化合物的LOD<10 ng/g,LOQ<30 ng/g,方法灵敏度高,检出限和定量限都较低。应用此方法检测了土壤、沉积物和污泥的实际样品,结果检出了多种紫外线吸收剂,说明紫外线吸收剂在环境中污染问题不容忽视。  相似文献   

9.
建立了沉积物中多氯联苯和有机氯农药等39种持久性有机污染物的同时测定方法。样品用正己烷和丙酮(体积比为1∶1)进行微波提取,提取溶液经凝胶色谱和弗罗里硅土净化,浓缩后采用气相色谱法测定。回收率在68.8%~84.2%,检出限为0.05~0.25ng/g。方法适用于沉积物样品中多种多氯联苯和有机氯农药含量的同时测定。  相似文献   

10.
采用同位素稀释法并结合凝胶渗透色谱净化技术,建立了植物油中多环芳烃残留的气相色谱-质谱(GC-MS)检测方法.样品中加入同位素替代物后,样品中的多环芳烃经乙腈-丙酮(体积比6∶4)溶液提取,共提取物中大部分的脂类、色素和蜡质经窄口径凝胶渗透色谱柱除去后,进行GC-MS测定,内标法定量.添加回收率为80%~110%,相对标准偏差小于15%.应用于FAPAS橄榄油有证标准样品,测定值与标准值一致.  相似文献   

11.
建立了一种利用三相液相微萃取(LPME)技术进行样品前处理、高效液相色谱(HPLC)法同时测定饮料中酒石酸、甲酸、乙酸、乳酸、琥珀酸、苹果酸和柠檬酸7种低相对分子质量有机酸的分析方法.考察了萃取溶剂、搅拌速率、盐效应、萃取时间、接收相和给出相pH值等因素对萃取效率的影响.优化后的实验条件:磷酸三丁酯(TBP)为萃取剂,萃取速率为1 000 r/min,萃取时间为35 min,给出相pH为2.5,接收相pH为12.0.该方法在较宽线性范围内显示了良好的线性关系(r>0.993 6),检出限(S/N=3)为10.4 ~54.2 μg/L,相对标准偏差小于4.8%.7种有机酸的富集倍数为13.3 ~51.4,样品的加标回收率为85% ~103%.该方法操作简单、快速,只需使用极少量的有机溶剂,具有绿色环保的特点,可用于果汁饮料、红茶饮料及基质特别复杂的牛奶饮料中低分子量有机酸的测定,为分析复杂基质样品提供了有益的参考.  相似文献   

12.
复杂基体中痕量多环芳烃分析测定方法的研究进展   总被引:15,自引:0,他引:15  
董新艳  杨亦文  任其龙 《色谱》2005,23(6):609-615
介绍了环境样品(水和土壤)以及植物油中痕量多环芳烃的分析检测方法。对样品的预处理过程和分析方法做了评价。采用一些新的预处理方法(包括液相色谱法、固相萃取法、超临界二氧化碳萃取法),并结合色谱-质谱在线联用分析检测方法能够获得比较理想的分析结果。引用文献52篇。  相似文献   

13.
血清总磷脂脂肪酸组分的固相萃取-气相色谱法分析   总被引:1,自引:0,他引:1  
以硅胶基质为固定相,建立了固相萃取-气相色谱(SPE-GC)分离检测血清总磷脂中脂肪酸含量的方法。优化了SPE的洗脱方式及甲醇洗脱量,探讨了衍生化步骤的优化条件。该法对磷脂中各脂肪酸组分测定的线性相关系数约为0.999,回收率在80%左右;日内误差小于4.8%,日间误差小于8.9%。用固相萃取柱分离磷脂简单、快速、有效,用气相色谱检测磷脂中脂肪酸组分方法稳定、可靠。  相似文献   

14.
In the present study, graphene oxide reinforced two‐phase electromembrane extraction (EME) coupled with gas chromatography was applied for the determination of methamphetamine as a model analyte in biological samples. The presence of graphene oxide in the hollow fiber wall can increase the effective surface area, interactions with analyte and polarity of support liquid membrane that leads to an enhancement in the analyte migration. To investigate the influence of the presence of graphene oxide in the support liquid membrane on the extraction efficiency, a comparative study was performed between graphene oxide and graphene oxide/EME methods. The extraction parameters such as type of organic solvent, pH of the donor phase, stirring speed, time, voltage, salt addition and the concentration of graphene oxide were optimized. Under the optimum conditions, the proposed microextraction technique provided low limit of detection (2.4 ng/mL), high preconcentration factor (195–198) and high relative recovery (95–98.5%). Finally, the method was successfully employed for the determination of methamphetamine in urine and hair samples.  相似文献   

15.
钟颖  于赤灵  彭平安 《色谱》2010,28(10):923-928
建立了固相萃取-离子色谱(IC)/气相色谱-质谱(GC-MS)联合检测高矿化度油田水中低相对分子质量的有机酸和酚类化合物的方法。在中性pH条件下,样品经Waters Oasis HLB柱萃取后,萃取液经稀释、Ag2O沉淀和Ag-H柱处理除去大部分氯离子,再用IC测定有机酸;将萃取柱真空冷冻干燥,然后经甲基叔丁基醚/甲醇(9:1, v/v)脱附并用无水硫酸钠除水,再用GC-MS检测酚类化合物。在优化的实验条件下,4种低相对分子质量的有机酸以及5种酚类化合物的平均加标回收率达到80%以上,相对标准偏差(RSD, n=6)为2.38%~9.45%,定量限均低于88.9 μg/L。该方法测定结果准确可靠,适用于氯离子含量高达150 g/L左右水样中低相对分子质量的有机酸和酚类化合物的检测。  相似文献   

16.
In this work, a new microextraction method termed ionic liquid based dispersive liquid-liquid microextraction (IL-DLLME) was demonstrated for the extraction of 2-methylaniline, 4-chloroaniline, 1-naphthylamine and 4-aminobiphenyl in aqueous matrices. After extraction the ionic liquid (IL) phase was injected directly into the high performance liquid chromatography (HPLC) system for determination. Some parameters that might affect the extraction efficiency were optimized. Under the optimum conditions, good linear relationship, sensitivity and reproducibility were obtained. The limits of detection (LOD, S/N = 3) for the four analytes were in the range of 0.45-2.6 μg L^-1. The relative standard deviations (R.S.D., n = 6) were in the range of 6.2-9.8%. This method was applied for the analysis of the real water samples. The recoveries ranged from 93.4 to 106.4%. The main advantages of the method are high speed, high recovery, good repeatability and volatile organic solvent-free.  相似文献   

17.
建立了固相萃取/高效液相色谱法测定肝癌细胞中多西紫杉醇浓度的方法。细胞样品经三氯乙酸沉淀蛋白,Bond-elut C18固相萃取柱提取,采用Agilent TC-C18(5μm,4.6 mm×150 mm)色谱柱分析,以乙腈-0.02 mol/L醋酸铵缓冲液(体积比50∶50,醋酸调至pH5.0)为流动相,流速为1 mL/min,检测波长为230nm,进样体积为20μL。多西紫杉醇的质量浓度在0.05~2.25 mg/L范围内线性关系良好,相关系数r=0.999 3,检出限为0.03 mg/L,提取回收率为93%~95%,其日内、日间精密度(n=5)不大于6.9%,且稳定性良好。方法简便、快速、灵敏度高、干扰小,可用于生物样品中低浓度多西紫杉醇的测定。  相似文献   

18.
In the present study, a new extraction method based on a three–phase system, liquid–liquid–liquid extraction, followed by dispersive liquid–liquid microextraction has been developed and validated for the extraction and preconcentration of three commonly prescribed tricyclic antidepressant drugs – amitriptyline, imipramine, and clomipramine – in human plasma prior to their analysis by gas chromatography–flame ionization detection. The three phases were an aqueous phase (plasma), acetonitrile and n–hexane. The extraction mechanism was based on the different affinities of components of the biological sample (lipids, fatty acids, pharmaceuticals, inorganic ions, etc.) toward each of the phases. This provided high selectivity toward the analytes since most interferences were transferred into n–hexane. In this procedure, a homogeneous solution of the aqueous phase (plasma) and acetonitrile (water–soluble extraction solvent) was broken by adding sodium sulfate (as a phase separating agent) and the analytes were extracted into the fine droplets of the formed acetonitrile. Next, acetonitrile phase was mixed with 1,2–dibromoethane (as a preconcentration solvent at microliter level) and then the microextraction procedure mentioned above was performed for further enrichment of the analytes. Under the optimum extraction conditions, limits of detection and lower limits of quantification for the analytes were obtained in the ranges of 0.001–0.003 and 0.003–0.010 μg mL−1, respectively. The obtained extraction recoveries were in the range of 79–98%. Intra– and inter–day precisions were < 7.5%. The validated method was successfully applied for determination of the selected drugs in human plasma samples obtained from the patients who received them.  相似文献   

19.
The quantification of phospholipid classes and the determination of their molecular structures are crucial in physiological and medical studies. This paper's target analytes are cell membrane phospholipids, which play an important role in the seasonal acclimation processes of poikilothermic organisms. We introduce a set of simple and cost‐effective analytical methods that enable efficient characterization and quantification of particular phospholipid classes and the identification and relative distribution of the individual phospholipid species. The analytical approach involves solid‐phase extraction and high‐performance thin‐layer chromatography, which facilitate the separation of particular lipid classes. The obtained fractions are further transesterified to fatty acid methyl esters and subjected to gas chromatography coupled to flame ionization detection, which enables the determination of the position of double bonds. Phospholipid species separation is achieved by high‐performance liquid chromatography with mass spectrometry, which gives information about the headgroup moiety and attached fatty acids. The total content of each phospholipids class is assessed by phosphorus determination by UV spectrophotometry. The simultaneous analysis of phosphorus, fatty acid residues, and phospholipid species provides detailed information about phospholipid composition. Evaluation of these coupled methods was achieved by application to an insect model, Pyrrhocoris apterus. High correlation was observed between fatty acid compositions as determined by gas chromatography and high‐performance liquid chromatography analysis.  相似文献   

20.
建立了中空纤维液相微萃取-高效液相色谱法测定纺织品中10种含氯苯酚类化合物的方法。系统地优化了影响萃取效率的因素,得到的最佳萃取条件为:萃取溶剂为正己烷,接受相NaOH溶液的浓度为0.10 mol/L,萃取时间为60 min,搅拌速度为600 r/min。在最佳萃取条件下,10种含氯苯酚在0.01~1.00 mg/L范围内线性关系良好(r>0.999),10种含氯苯酚的检出限(信噪比为3)为0.01 mg/kg,富集倍数为95~101。在空白样品中添加0.01、0.05和0.1 mg/kg 3个不同水平的10种含氯苯酚类化合物,其平均回收率为78.8%~105.1%,相对标准偏差为0.3%~7.3%。研究结果表明该方法灵敏度高、简便、准确,可用于纺织品中含氯苯酚类化合物的测定。  相似文献   

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