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1.
研究建立了一种复杂食品基质中7种常见防腐剂同时检测的分散液液微萃取-气相色谱方法。分散液液微萃取是一种集萃取和富集于一体的高效、快捷样品前处理方法。样品中防腐剂用去离子水超声提取后,调节pH,加入分散剂丙酮0.6 mL,加入氯化钠0.8 g,加入萃取剂四氯化碳0.3 mL,手动振摇100次,涡旋30 s,再手动振摇100次,离心后取离心管底部有机相分析。7种防腐剂在(2~400)μg范围内线性良好,r~2为0.9990~0.9995,检出限为(0.1~0.2)mg/kg,7种物质分离度均≥3.9,回收率为90.8%~101.4%,相对标准偏差为2.2%~4.8%。在前人研究的基础上,将分散液液微萃取技术运用到复杂食品基质中多种常用防腐剂的检测,通过萃取剂和分散剂体积的优化,实现了萃取后有机相的自动进样,实现了批量化上机操作。该法主要方法学指标均达到或超过国家标准方法。  相似文献   

2.
建立了超声辅助分散液液微萃取(UA-DLLME)高效液相色谱(HPLC)法测定棉花中脱叶剂残留量的分析方法。样品经超声提取后,向提取液中快速注入乙腈(分散剂)和四氯化碳(萃取剂),采用UA-DLLME法分离富集分析目标物,并通过HPLC法进行定性定量分析。结果表明,6种脱叶剂的线性关系良好,相关系数为0.998 0~0.999 9,检出限(LOD)为0.5 mg/L,加标回收率为85%~100%,相对标准偏差RSD为2.09%~6.33%。该方法操作简便、快捷、准确,可以用于棉花中脱叶剂残留量的测定。  相似文献   

3.
目的建立分散液液微萃取-超高效液相色谱-串联质谱法测定凉茶中6种有机磷残留量的方法。方法样品经N-丙基乙二胺(N-Propylethylenediamine,PSA)固相萃取剂预净化后,以甲醇为分散剂,三氯甲烷为萃取剂进行提取。在优化后的仪器条件下,采用电喷雾离子化正离子模式电离,多反应监测模式进行测定。结果 6种有机磷的标准曲线在2.0~200μg/L范围内线性良好,相关系数r2均大于0.9990,在添加水平为0.25、0.50和2.5μg/kg的加标回收试验中,平均回收率范围为73.6%~99.5%,相对标准偏差为1.14%~8.01%,方法检出限和定量限为0.02~0.04μg/kg和0.06~0.10μg/kg。结论该方法操作简单便捷、富集倍数高、灵敏度高、重现性好,可用于实际市售凉茶产品的质量监督。  相似文献   

4.
建立温控辅助离子液体分散液液微萃取结合高效液相色谱-二极管阵列检测器法检测果汁中7 种杀菌剂农药残留的新方法。对影响萃取效果的因素萃取剂和分散剂类型及体积、溶解温度、萃取时间和离心时间进行优化。在优化后的方法条件下,7 种杀菌剂富集倍数可达64~101;方法检出限在4.3~13.0 μg/L之间;在0.02、0.05 mg/L和0.10 mg/L三个水平下加标,果汁(苹果汁、梨汁、葡萄汁、桃汁和橙汁)的平均加标回收率在70.0%~116.2%范围内,相对标准偏差均小于9.8%,能满足多种果汁中杀菌剂农药多残留检测的要求。  相似文献   

5.
目的 建立一种基于低共熔溶剂(deep eutectic solvent,DES)液液微萃取结合高效液相色谱法检测调味油中6种工业染料的分析方法。方法 合成了8种不同DESs并对比了其对酸性橙Ⅱ、碱性橙2、碱性橙21、碱性橙22、碱性嫩黄O、罗丹明B的萃取效率,研究了取样量、DES摩尔比、DES添加量以及正己烷添加比例对萃取率的影响。结果 结果表明采用氯化胆碱:L(+)乳酸(摩尔比1:3)组成的DES,当取样量1 g,添加1 mL正己烷,DES用量600 μL的条件下萃取率最高。6种工业染料在0.05 ~ 2 mg/L (罗丹明B:0.05 ~ 2 μg/L)浓度范围内线性关系良好,相关系数均大于0.9998,在0.05、0.10、1.00 mg/kg(罗丹明B:0.05、0.10、1.00 μg/kg)三个不同浓度添加水平下回收率为67.5% ~ 111.5%,相对标准偏差为1.8% ~11.6%,检出限为0.02~20 μg/kg,定量限为0.05~50 μg/kg。结论 该方法对调味油中6种工业染料有很好的选择性和萃取效果,采用绿色环保的DES萃取目标物,减少了有机试剂的用量,具有较好的应用前景。  相似文献   

6.
目的:建立一种液液萃取净化的高效液相色谱法测红茶中的赭曲霉毒素A的方法。方法:试样经60%乙腈超声提取,液液萃取净化,以甲醇~0.5%乙酸梯度洗脱,C18短柱分离后经高效液相色谱仪-荧光检测器检测。结果:赭曲霉毒素A在10.00μg/L~50.00μg/L浓度范围,相关系数为1.00000,加标回收率为83%~98%,RSD为1.11%~2.47%,检出限为0.0052mg/kg。结论:仪器20min完成一个样品测定,方法检测速度快,同时具有净化效果好,精密度和准确度高的特点。  相似文献   

7.
目的 建立氢氧化钡碱溶液-分散液液微萃取结合气相色谱-串联质谱法(gaschromatography-tandem massspectrometry,GC-MS/MS)同时测定肉制品中9种N-亚硝胺类化合物的分析方法。方法 肉制品样品在80℃水浴中经氢氧化钡碱溶液皂化,去除油脂干扰,进一步将N-亚硝胺提取到水溶液中,再加入甲醇(分散剂)和二氯甲烷(萃取剂)进行高效萃取富集,在多反应监测模式下分析,稳定同位素内标法定量。对影响萃取效率的因素进行考察,如样品提取步骤中的皂化条件,无机盐、萃取剂和分散剂的种类及体积等。通过优化色谱、质谱参数和前处理条件,获得最佳检测结果。结果 除了N-亚硝基二甲胺(N-nitrosodimethylamine, NDMA)的线性范围为2.5~50.0 ng,其他8种N-亚硝胺类化合物在1.0~50.0 ng范围内线性关系良好, 9种N-亚硝胺类化合物的相关系数(r2)范围为0.9954~0.9999,方法检出限和定量限分别为0.1~0.2μg/kg和0.2~0.5μg/kg。在火腿、五香鸡肉和牛肉样品中分别进行0.5、5.0μg/kg浓度水平的加标实验,所有...  相似文献   

8.
建立一种快速简便的超声辅助离子液体-分散液液微萃取(UA-IL-DLLEX)-高效液相色谱荧光法(HPLC-FD),分析蔬菜中速灭威、克百威、甲萘威、异丙威4种氨基甲酸酯类农药残留。考察系列影响萃取率的参数,包括萃取剂和分散剂的种类及其体积、样品p H、盐浓度、超声萃取时间。优化的萃取条件:200μL离子液体(IL,[C_6MIm][PF_6])为萃取剂,100μL四氢呋喃(THF)为分散剂,样品pH为7.0,不加盐,超声萃取5 min。在此条件下,方法的线性范围为0.02~1.0μg/m L,相关系数大于0.999,检出限(S/N=3)为0.006 3~0.018 mg/kg,3种阴性蔬菜中3个水平0.167,0.033和0.066 mg/kg的加标回收率为83.2%~110%,6次测定的相对标准偏差(RSD)为2.2%~5.1%。该方法应用于肇庆地区20种蔬菜中氨基甲酸酯类农药残留检测,所有蔬菜样品中均未检出速灭威、甲萘威和异丙威,6种蔬菜样品检出克百威浓度为0.017~0.22 mg/kg。  相似文献   

9.
采用涡旋辅助分散液液微萃取(DLLME)-气相色谱(GC)法测定清香型白酒中5种高级醇的含量。结果表明,最佳液液微萃取的提取条件为萃取剂二氯甲烷60 μL、分散剂丙酮100 μL、样品pH值5.5、酒精度15%vol、NaCl质量浓度0.19 g/mL、萃取时间30 s。在此优化条件下,正丙醇和异丁醇在含量为1.00~40.00 mg/L、异戊醇在含量为1.00~150.00 mg/L、2,3-丁二醇在含量为1.25~50.00 mg/L和β-苯乙醇在含量为0.25~10.00 mg/L的范围内具有较好的线性关系(R2>0.99);检出限分别为0.03 mg/L、0.01 mg/L、0.01 mg/L、0.02 mg/L和0.02 mg/L;精密度试验结果相对标准偏差(RSDs)<7.0%,回收率为83.1%~108.3%。6种清香型白酒中正丙醇含量范围为0.064~0.116 g/L、异丁醇含量范围为0.057~0.127 g/L、异戊醇含量范围为0.262~0.450 g/L、2,3-丁二醇含量范围为0.017~0.035 g/L、β-苯乙醇含量范围为0.008~0.012 g/L。  相似文献   

10.
采用分散液液微萃取(DLLME)结合气质联用法(GC-MS)测定染料中21种禁用芳香胺。试验确定了萃取剂和分散剂,并对试剂用量、萃取时间和盐效应等参数进行优化。结果表明,在本试验确定条件下,新方法对染料中21种禁用芳香胺的富集倍数达到79~172倍,检出限为0.3~1.2mg/kg,线性范围为1~50mg/kg,平均加标回收率为86.5%~102.3%,相对标准偏差为2.40%~9.67%。该方法高效快捷、易操作,且减少了有机溶剂使用量,安全环保。  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.
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   

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17.
A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.  相似文献   

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19.
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   

20.
<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   

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