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1.
建立了同时测定焙烤食品中丙烯酰胺、4-甲基咪唑和5-羟甲基糠醛的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法。样品中加入同位素内标后,以水和乙腈超声提取,QuEChERS净化,正己烷脱脂,UPLC-MS/MS分离检测,丙烯酰胺和4-甲基咪唑以同位素内标定量。在优化条件下,3种待测物的方法检出限在1.5μg/kg~7.0μg/kg之间;在2.0μg/L~500μg/L浓度范围内线性关系良好,相关系数均大于0.9990;在面包、蛋糕和饼干样品中进行3个水平的添加实验,平均回收率(n=6)为87.8~115.7%,日内精密度为3.2~9.6%;日间精密度(n=5)小于11.5%。本方法净化效果好,灵敏度高、准确性好,适用于焙烤食品中丙烯酰胺、4-甲基咪唑和5-羟甲基糠醛的同时测定。  相似文献   

2.
建立了超高效液相色谱-质谱/质谱联用法(ultra-performance liquid chromatography-mass spectrometry/mass spectrometry, UPLC-MS/MS)同时分析葡萄酒中41种农药和7种真菌毒素残留的方法。样品经QuEChERS净化,UPLC-MS/MS测定,外标法定量。结果表明,48种待测物质在各自线性范围内呈现良好的线性关系,相关系数均大于0.999,检出限为0.01~5μg/kg,定量限为0.05~17μg/kg;在25、50、80μg/kg加标水平下平均回收率为79.6%~122.5%,相对标准偏差(relative standard deviation, RSD,n=6)为0.21%~6.39%。该方法前处理简单、稳定性好,可以广泛应用于葡萄酒中农药和真菌毒素残留的快速筛查和定量检测。  相似文献   

3.
建立超高效液相色谱-串联质谱(UPLC-MS/MS)测定蔬菜中氨基甲酸酯类农药的方法。用乙腈提取蔬菜中的氨基甲酸酯类农药,经QuEChERS净化后UPLC-MS/MS定量分析。实验浓度范围内线性关系良好,方法加标回收率在82.2%~104.1%,精密度(RSD)为1.9%~4.0%,检出限为0.2~1.5μg/kg。UPLC-MS/MS法测定蔬菜中氨基甲酸酯类农药有较好的回收率、重现性和较低的检出限,能满足大批量样品氨基甲酸酯类农药的快速检测需求。  相似文献   

4.
建立了同时测定酱油中8种生物胺的超高效液相色谱-串联质谱(UPLC-MS/MS)分析方法。样品中加入1,7-庚二胺作为内标,以水稀释和氨水调节p H值后,加入乙腈进行液液萃取,盐析分层,萃取液经QuEChERS净化,调整酸度、浓缩、复溶后,以UPLC-MS/MS分离测定,内标法定量。在优化条件下,8种待测物在5.0μg/L~500μg/L浓度范围内线性关系良好,相关系数均大于0.998;方法检出限为30μg/kg~60μg/kg,方法定量限为120μg/kg~250μg/kg;在酱油样品中进行2个水平的添加实验(n=6),平均回收率为83.7%~110%,相对标准偏差为3.8%~11.5%。实际酱油样品检测结果显示,酱油中酪胺和苯乙胺的含量最高。本方法准确、灵敏、快速,适用于酱油中8种生物胺的同时测定。  相似文献   

5.
目的:建立超高效液相色谱-串联质谱法(Ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)同时测定婴幼儿配方乳粉中氯酸盐和高氯酸盐。方法:样品经过提取、离心、固相萃取柱净化和过滤,净化后滤液经负离子模式测定,并用内标法进行定量。结果:氯酸盐和高氯酸盐分别在2~500 μg/kg和1~250 μg/kg线性关系良好(R;>0.999),检出限均为4.5 μg/kg,定量限分别为15 μg/kg和7.5 μg/kg。对于方法正确度(n=9),在15.0、30.0 μg/kg和150 μg/kg 3个加标水平下,氯酸盐回收率为90.4%~104.3%;在7.5、15 μg/kg和75 μg/kg 3个加标水平下,高氯酸盐回收率为80.2%~106.2%。对于方法精密度(n=7),氯酸盐RSD为4.74%,高氯酸盐RSD为8.31%。结论:该方法线性、精密度和正确度数据均满足GB/T 27417—2017《化学分析方法确认和验证指南》的要求,适用于婴幼儿配方乳粉中氯酸盐和高氯酸盐的同时分析检测。  相似文献   

6.
建立辣椒中33种农药残留QuEChERS净化,气相色谱质谱联用仪快速的检测方法。乙腈超声提取,N-正丙基乙二胺(primary secondary amine,PSA)和C18净化,经HP-5MS色谱柱分离后测定。在测定浓度范围0.4μg/m L~20.0μg/m L内线性关系良好,r0.995;添加浓度为25、80、150μg/kg时平均回收率为74.31%~119.72%,相对标准偏差为2.0%~15.3%(n=6),检出限(LOD)为0.02μg/kg~4.6μg/kg,定量下限(LOQ)为0.07μg/kg~15.3μg/kg。本方法适用于辣椒中33种农药残留的检测。  相似文献   

7.
建立了QuEChERS萃取-UPLC-MS/MS测定花生酱中黄曲霉毒素B1的快速检测方法。样品首先经过1%甲酸-乙腈溶液提取,提取液采用QuEChERS净化试剂(250mg MgSO4+100mg HC-C18+50mg PSA)净化后上机,UPLC-MS/MS正离子源多反应模式检测,外标法定量。黄曲霉毒素B1在1.0~5.0ng/mL范围内呈良好线性关系,相关系数(R^2)>0.999,4个水平的添加目标分析物黄曲霉毒素B1的回收率在81.7%~93.5%范围内,相对标准偏差(RSD)为2.4%~5.6%,检出限为0.03μg/kg;该试验方法具有简单、高效、经济、准确、回收率高、精密度好的优点,适用于花生酱样品中黄曲霉毒素B1的快速检测。  相似文献   

8.
目的:基于检出限、精密度、准确度、加标回收率等指标,考查超高效液相色谱-串联质谱法(UPLC-MS/MS)和高效液相色谱法(HPLC)测定苹果中氨基甲酸酯类农药的一致性及适用性。方法:分别采用UPLC-MS/MS法和HPLC法测定苹果中的氨基甲酸酯类农药。UPLC-MS/MS法:苹果样品中的氨基甲酸酯类农药经乙腈提取,QuEChERS净化后,UPLC-MS/MS进行分离并定量分析;HPLC法:苹果样品中的氨基甲酸酯类农药经乙腈超声提取后,CARB/NH_2固相萃取柱净化,高效液相色谱-柱后衍生法进行分离并定量分析。结果:HPLC法加标回收率在79%~83%,日内精密度(RSD%)为1.9%~5.3%,方法检出限为2.0~5.0 μg/kg;UPLC-MS/MS法加标回收率在83.2%~103.1%,日内精密度(RSD%)为0.9%~3.1%,方法检出限为0.5~1.5 μg/kg。结论:相较于HPLC法,UPLC-MS/MS 法保留时间更短、检出限更低,且操作简便、重现性好,可作为苹果中氨基甲酸酯类农药残留检测的推荐方法。  相似文献   

9.
试验旨在采用气相色谱-质谱联用法测定婴幼儿配方乳粉中壬基酚的含量。最佳试验条件是采用乙腈作为样品的提取溶剂,使用弗罗里硅土作为试验用净化固相萃取小柱,经衍生化,用气相色谱-质谱联用仪测定;测得壬基酚各同分异构体的检出限在0.055~0.51μg/kg之间;标准曲线范围在5~250μg/L之间,线性关系在0.998以上;加标浓度在0.003~0.3 mg/kg范围内的回收率为67.5%~107.2%,方法的精密度为0.54%~7.51%(n=6)。该方法具有提取简单、灵敏度高、回收率好、重复性好等优点。实现了大批量婴幼儿配方乳粉中壬基酚的定性定量检测,满足了市场上婴幼儿奶粉中质量监督检查的需要。  相似文献   

10.
建立了超高效液相色谱-串联质谱(UPLC-MS/MS)测定甘蔗中11种多酚类物质含量的方法。样品经甲醇超声提取,采用UPLC-MS/MS进行分析检测,电喷雾负离子电离(ESI-),多反应监测(MRM)检测,外标法定量。该方法在5~200μg/L范围内线性良好(r2>0.999),检出限为0.5~17.0μg/kg。在样品中添加100μg/kg的11种多酚标准溶液,回收率为89.4%~102.4%,相对标准偏差为0.9%~4.3%(n=6)。此方法简便快捷,灵敏度高,适用于甘蔗中多酚类物质的定性定量分析。  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.
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   

17.
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   

18.
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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