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1.
吕岱竹 《食品科学》2010,31(12):174-177
为建立超声波提取热带水果中环境激素壬基酚聚氧乙烯醚及降解产物壬基酚、液相荧光法测定残留量的方法,对超声提取的温度、时间、功率进行条件优化,提取液经净化浓缩后,用C18 色谱柱进行分离,液相色谱荧光法进行测定。结果表明:样品中壬基酚聚氧乙烯醚及壬基酚在0.5~50μg/mL 范围内线性良好,检出限分别为0.04mg/kg 和0.008mg/kg,方法回收率分别为92%~102% 和75%~92%。该方法快速灵敏、准确度高,符合残留检测的要求。  相似文献   

2.
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   

3.
通过乙酸乙酯超声提取技术,采用气相色谱-质谱联用法测定了纺织品中的4-叔丁基苯酚。在优化条件下,4-叔丁基苯酚的响应信号和浓度(0.02mg/L~2.0mg/L)的线性关系良好。该方法检测限为0.08mg/kg,在0.2mg/kg、0.4mg/kg、2.0mg/kg加标水平下回收率为88.8.0%~110.8%,相对标准偏差为3.5%~8.8%。试验证明该方法检测限低,回收率高,适用于纺织品中4-叔丁基苯酚的分析检测。  相似文献   

4.
建立高效液相色谱-串联质谱法测定食品用塑料包装中壬基酚的迁移量。样品经迁移试验得食品模拟物,水性模拟物直接上机,油基模拟物经甲醇提取、冷冻离心后取上清液分析,外标法定量。在本试验条件下,壬基酚线性关系良好,6种模拟物的相关系数都达到0.998 5以上,两类模拟物的检出限分别为0.01 mg/L和0.01 mg/kg,回收率为89.3%~94.4%,RSD值为2.76%~3.37%。该法简单、灵敏、准确,适用于食品用塑料包装中壬基酚迁移量的检测。  相似文献   

5.
目的建立植物油中9种农药残留量的内标检测方法。方法样品用乙腈提取,经优化的Qu ECh ERS方法净化,气相色谱-质谱联用仪测定,内标法定量。结果氟乐灵、甲拌磷、七氯、倍硫磷、反-氯丹、顺-氯丹的线性范围为0.005~0.2 mg/L,检出限为0.01 mg/kg;α-硫丹、β-硫丹的线性范围为0.01~0.2 mg/L,检出限为0.02 mg/kg;多效唑的线性范围为0.02~0.2 mg/L,检出限为0.04 mg/kg。结论本方法准确度高、重复性好,前处理无需特殊仪器,且内标物的引入进一步降低了前处理的操作难度,为方法的推广创造了更好的条件。  相似文献   

6.
《食品与发酵工业》2014,(2):192-195
建立了一种简单、快速,同时检测水果中赤霉素、多效唑和烯效唑残留量的固相萃取-高效液相色谱(SPE-HPLC)方法。该方法经80%甲醇水提取样品,C18固相萃取小柱净化,采用DAD检测器220 nm紫外扫描检测。结果表明:3种植物生长调节剂在0.510μg/mL内线性关系良好(r≥0.999);检出限分别为赤霉素0.002 mg/kg、多效唑0.04 mg/kg、烯效唑0.02 mg/kg;在0.210μg/mL内线性关系良好(r≥0.999);检出限分别为赤霉素0.002 mg/kg、多效唑0.04 mg/kg、烯效唑0.02 mg/kg;在0.20.8 mg/kg加标水平下,3种植物生长调节剂平均回收率为78%0.8 mg/kg加标水平下,3种植物生长调节剂平均回收率为78%91%;相对标准偏差为2.4%91%;相对标准偏差为2.4%5.4%。  相似文献   

7.
目的:基于高效液相色谱—串联质谱技术,建立一种检测食品包装材料中双酚A和壬基酚的方法.方法:用不同的提取溶剂和提取方法提取标准样品中的双酚A和壬基酚,以目标物的提取量为指标确定最佳提取溶剂和提取方法,在此基础上考察固相萃取柱、上样溶剂、淋洗溶剂及洗脱溶剂对净化效果的影响.样品以二氯甲烷为溶剂超声提取后经硅胶固相萃取柱净化,用Venusil MPC18(2)色谱柱(100mm×2.1mm,2.6μm)进行分离,以0.1%氨水和甲醇为流动相进行梯度洗脱,在ESI负离子扫描模式下采用多反应监测模式测定,内标法定量.结果:双酚A和壬基酚在1.0~200.0μg/L范围内均具有良好的线性关系,相关系数R>0.999,在1.0,10.0,200.0μg/kg3个加标水平下的平均回收率为89.2%~101.2%,相对标准偏差(RSD)为3.1%~6.2%.方法的检测限和定量限分别为0.5,1.0μg/kg.结论:该方法操作简单、准确、灵敏,可适用于食品包装材料中双酚A和壬基酚含量的测定.  相似文献   

8.
目的:建立蔬菜中辛硫磷农药残留量的气相色谱测定方法。方法:样品采用乙腈提取,经浓缩用丙酮定容,在优化的气相色谱条件下进行测定。结果:标准曲线线性相关性好,相关系数r为0.999 95,添加量在0.02 mg/kg、0.10 mg/kg和0.50 mg/kg,即添加低、中、高3个水平浓度下,平均回收率为97.4%~99.9%,相对标准偏差0.36%~3.80%,检出限0.01 mg/kg,定量限0.03 mg/kg。结论:该方法具有灵敏度高、分析速度快、重现性好等特点,满足蔬菜中对辛硫磷农药残留分析要求。  相似文献   

9.
采用高效液相色谱串联质谱法研究并优化纺织品中三种六溴环十二烷(HBCD)的检测方法。纺织样品经过丙酮自动索氏提取、浓缩、甲醇定容,采用HPLC-MS/MS对三种HBCD进行检测。HPLC-MS/MS的优化条件为:流动相V(甲醇)∶V(乙腈)∶V(水)=40∶40∶20,三种HBCD的定量离子和辅助定性离子对为:m/z 640.6/80.8和m/z 640.6/78.9。待测物质量浓度为0.01~0.50 mg/L时,线性相关系数大于0.999,α-HBCD、β-HBCD和γ-HBCD的测定低限分别为0.01 mg/kg、0.02 mg/kg、0.02 mg/kg,空白样品的加标回收率在85%~105%。  相似文献   

10.
研究微波辅助提取,反相高效液相色谱测定花菜中VC含量的方法。花菜匀浆后,以1%草酸溶液为提取溶剂,微波提取、固相萃取小柱净化后,采用恒流的方法进行液相色谱定量检测,以0.1%草酸溶液为流动相,流速1.0 m L/min,采用C-18反相色谱柱分离,在254 nm波长下检测。结果表明VC浓度在0.02 mg/m L~0.12 mg/m L范围内线性良好,相关系数为0.999 6,检测限0.02 mg/kg,回收率在99.9%~104.6%之间,相对标准偏差为1.20%。该方法能有效提取蔬菜中Vc,测定结果稳定,准确度高,重现性好,可以用于蔬菜中VC的检测。  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   

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This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.  相似文献   

18.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

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