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1.
通过液液分配和固相萃取提取、净化动物组织中添加的莱克多巴胺,TMS衍生化试剂BSTFA(N,O-双(三甲基硅烷基)三氟乙酰胺)衍生化,气相色谱-质谱联用(选择离子模式,选择离子为m/z163、m/z192、m/z234、m/z250)对衍生物检测分析,确定了动物组织中莱克多巴胺的定性、定量分析方法,该法检出限为0.5μg/L,衍生物的峰面积与样品浓度在1~1000μg/L范围内呈良好的线性关系,线性回归系数为0.9998。不同组织中不蚓莱克多巴胺加入量的加标回收率分别为:肝脏70.2%-75.4%,脂肪71.2%-84.7%,肾脏72.8%-80.9%,肌肉75.2%-86.4%;相对标准偏差为1.8%-5.6%。  相似文献   

2.
通过液液萃取和固相萃取提取、净化奶与奶制品中添加的雌酮,以TMS衍生化试剂BSTFA衍生化,气相色谱-质谱联用(选择离子模式,选择离子为m/z218、m/z244、m/z257、m/z342)对衍生物检测分析,确定了样品中雌酮的定性、定量分析方法,该法检出限为0.2μg/kg,定量限为0.8μg/kg。衍生物的峰面积与样品质量浓度在0.5~1000μg/L范围内呈良好的线性关系,线性回归系数为0.999。雌酮不同加入量的添加回收率为70.1%~93.6%,变异系数为2.0%~3.7%。该方法可实现对样品进行灵敏、准确的定性定量分析。  相似文献   

3.
徐竞 《面粉通讯》2009,(3):37-39
建立了面粉中三聚氰胺的高效液相色谱-质谱测定方法。色谱条件:Kromasil C18柱(4.6mm×250mm,5μm),流动相:乙腈-0.1%(体积分数)甲酸(体积比5:95),流速0.4mL/min。采用正离子模式的电喷雾质谱检测,以一级质谱得到的准分子离子m/z127作为母离子,进行碰撞诱导解离二级质谱分析,选择母离子和MS的碎片离子m/z85、109定性确证,提取m/z85、109、127三个离子质量色谱峰面积定量。线性范围为0.01-0.5mg/L,检出限0.01mg/L,回收率为80%~99%。  相似文献   

4.
采用高效液相色谱.电喷雾串联质谱测定尿液中硝西泮的代谢物7-氨基硝西泮。测定时尿液中加入内标7-氨基氯硝西泮,经过β-葡萄糖醛酸酸苷酶水解,碱性液萃取,过0.45μm的滤膜,反相色谱分离后进行质谱分析,在选择反应监测模式(SRM)下进行特征母.子离子对信号采集。根据保留时间、母离子和特征子离子信息进行定性分析,内标法进行定量。药物检测限(LOD,S/N=3)为0.07μg/L,定量限(LOQ)为0.5μg/L,线性范围为1~50μg/L。在1.0、10.0、25.0、45.0μg/L四个添加水平下,回收率范围为89.0%~95.2%,相对标准偏差(RSD)小于6.4%。结果表明,该法简单、灵敏、重现性强,适用于尿液中7-氨基硝西泮的分析确证。  相似文献   

5.
陈军  张燕 《印染》2006,32(1):39-41
建立了纺织品游离甲醛的衍生.萃取.气质联用测定方法:试样剪碎后置于饱和NaCl溶液中,60℃超声波超声处理30min,用五氟苯盐酸氢胺衍生化后,采用顶空固相微萃取和色质联用技术(HS-SPME-GC-MS),选择离子(m/z181)进行定量。该方法适用于各类单层或多层纤维织物中甲醛的测定,加标回收率94.9%-98.7%,相对标准偏差2.97%-4.59%;方法检出限为0.02mg/kg。  相似文献   

6.
蒋小良 《中国纤检》2012,(18):60-62
本文建立了以酸性人工汗液提取,冷蒸气发生-原子吸收光谱法测定纺织品中可萃取痕量镉的方法。研究了载气流速、还原剂的选择、增敏剂加入量、介质酸度以及共存离子的干扰等因素。在试验选定的最佳条件下,镉浓度在0.05μg/L~40.0μg/L呈良好线性关系,相关系数≥0.9993,方法检出限为0.020μg/L,样品加标回收率为90.8%~106.1%,相对标准偏差小于3.8%。该方法灵敏度高、操作简单、干扰小,用于纺织品中可萃取痕量镉测定,结果满意。  相似文献   

7.
研究在酸性条件下用吡咯烷二硫代甲酸铵和二乙氨基二硫代甲酸钠及甲基异丁酮(APDC+DDTC—MIBK)体系萃取富集碳酸饮料消化液中铜离子,再用石墨炉原子吸收法测定铜离子含量的检测方法。并对实验条件进行优化,确定最佳消化体系:HNO3-HClO4(5+2),方法检出限为0.2653μg/L,特征灵敏度为0.2122μg/L。线性范围为1.5μg/L~10μg/L,相关系数为0.9993,加标回收率为95,79%-100.74%,相对标准偏差为3.13%~5.06%。  相似文献   

8.
建立了液相色谱.串联质谱外标法检测纺织品中可分解4-氨基偶氮苯的方法,样品在碱性条件下用连二亚硫酸钠还原裂解,经液一液萃取,4000r/min离心处理取上清液用0.45μm针头式过滤器过滤后进行分析测定。使用ZORBAXSB—C182.1mm×30mm、3.5μm液相色谱柱分离,采用串联质谱多反应监测模式进行定性定量分析。试验结果表明,在2.5μg/L~125μg/L范围内,峰面积和浓度线性关系良好,相关系数R2=0.999。3种浓度水平加标回收率N67.4%~78.5%,方法检出限10μg/kg。满足纺织品中可分解4一氨基偶氮苯分析的要求。  相似文献   

9.
对实验室制得的雌酮特异性抗体A—E1和针对雌酮、雌二醇、雌三醇的广普性抗体A一17E2进行了效能指标的系统评价,建立了雌酮测定的直接竞争ELISA方法。其结果两者检测雌酮的灵敏度分别可达1.3μg/L±0.06μg/L和1.5μg/L±0.05μg/L,检出限分别可达0.04μg/L±0.01μg/L和0.07μg/L±0.01μg/L。此外,A-17E2对于雌二醇和雌三醇的检测灵敏度分别可达1.5μg/L和18μg/L,对两者的检出限分别可达0.04μg/L和0.2μg/L,证明此种广普性抗体可有效检测雌酮,同时对雌二醇、雌三醇也有良好的检测效果。  相似文献   

10.
高效液相色谱-质谱联用测定乳制品中6种四环素类抗生素   总被引:2,自引:0,他引:2  
建立了乳制品中6种四环素类抗生素残留的高效液相色谱-电喷雾离子阱质谱联用测定方法。该方法采用多反应监测正离子模式,可一次对6种四环素类抗生素进行定性和定量分析。该方法的检出限0.5-4.0μg/L,测定低限牛奶0.6-4.5μ/L,乳粉为6.0-45.0μg/kg,线性范围4.0-100.0μg/L,加标回收率56.1%-104.9%,相对标准偏差为2.5%-15.0%。该法具有样品预处理简单,灵敏度高,分析时间短等优点。  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.  相似文献   

13.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

14.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

15.
Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH3CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH2PO4-20.6 mM Na2B4O7 buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.  相似文献   

16.
An investigation is described in which various polyfunctional compounds were applied to wool in attempts to stabilize the temporary improvements in wrinkle-recovery brought about by ‘annealing’. Several reactive systems involving formaldehyde were found to produce the desired permanently improved wrinkle-recovery.  相似文献   

17.
18.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

19.
BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H2O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.  相似文献   

20.
《造纸信息》2014,(8):79-79
Ministr y of Industr y and Information Technology confirmed that the main expected targets for energysaving and comprehensive utilization in 2014 are:energy consumption and CO2 emissions per unit of industrial added-value decreases by 4.5%,water consumption per ten thousand Yuan of industrial added-value decreases by7%,comprehensive utilization of industrial solid waste is further improved,and pollution emissions in key industries is markedly reduced.  相似文献   

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