电感耦合等离子体质谱法测定烟草中的微量硼

通过优化微波消解样品前处理条件和仪器参数,建立了电感耦合等离子体质谱法(ICP-MS)测定烟草中硼元素含量的分析方法。结果表明:该方法硼元素检出限为0.05μg/L,样品加标回收率为97.9%~102.2%,精密度(RSD)为3.5%(n=6)。该方法简单、快速、准确,适合用于烟草中硼元素的测定。     

全自动测汞仪检测食品中总汞方法的建立与应用

本实验参照GB 5009.17-2014《食品中总汞及有机汞的测定》方法,确立了DMA-80全自动测汞仪测定汞含量的方法。实验测定了热解温度对实验方法的影响,采用土样标准物质测定标准曲线,确定线性方程,测定了本方法的检出限(需要的参数包括标准偏差SD和线性斜率B),并计算了此方法的精密度,还测定了样品(包括奶粉、牛奶)加标回收率。结果表明:本方法线性范围是0.28~10.12ng,绘制的标准曲线为y=17633x+2440.3,相关系数r~2=0.9967。检出限为0.015ng,加标回收率为108.77%~114.47%,相对标准偏差(RSD)处于0.4%~4.6%之间,在5.0%范围内。质控样品是由中国计量科学研究院生产的标准参考物质GBW 10018鸡肉,其测定值均在标准值范围内。     

高通量密闭微波消解-ICP-MS测定食品中的锗含量

建立高通量密闭微波消解样品-电感耦合等离子体质谱仪(inductively coupled plasma mass spectrometer,ICP-MS)测定食品中锗含量的检测方法。试验研究高通量密闭微波消解样品和高压密闭罐消解样品测试结果比对试验、锗的干扰试验、方法的检出限、精密度和准确度试验、加标回收试验,结果表明:方法检出限为:0.9 μg/kg;相对标准偏差(relative standard deviation,RSD)为5.1 %~17.8 %之间;相对误差(relative error,RE)为2.7 %~12.6 %之间;加标回收率在94.0 %~105 %之间,满足DD2005-03《区域生态地球化学调查评价样品分析技术要求》中的质量控制要求。对不同种类食品标准物质进行测定验证方法的准确度,测定结果与标准值相吻合。     

超声萃取-气相色谱法同时测定皮革及其制品中21种有害有机溶剂的残留量

建立了一个能同时测定皮革及其制品中21种有害有机溶剂残留量的气相色谱方法,该方法以乙酸乙酯为提取溶剂,45℃下超声提取皮革及其制品中残留的有害有机溶剂,提取液经固相萃取柱净化后进行气相色谱-火焰离子检测器(GC-FID)分析,外标法定量。该方法操作简单,定量准确,检出限低,各组分的检出限为0.05~0.50 mg/kg,在3个不同加标水平下,加标平均回收率为81.13%~96.47%,精密度实验RSD为3.11%~4.71%(n=9)。采用该方法对512个市售皮革样品进行测定,在39个样品中检出不同含量水平的多种目标分析物。     

微波消解-电感耦合等离子体质谱联用法检测岳阳市3大名优特产中金属元素含量

目的建立微波消解-电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)测定岳阳市3大名优特产中金属元素含量的分析方法。方法样品经微波消解后,采用蠕动泵在线加入内标,用ICP-MS测定岳阳的茶叶、银鱼、莲子中Pb,Cd,Cr,As,Hg 5种金属元素的含量。结果各元素在其标准曲线范围内线性关系良好,检出限为0.0003~0.010mg/kg,表明方法的灵敏度较高;各元素的加标回收率为86.4%~107.9%,相对标准偏差(relative standard deviation,RSD)为2.84%~8.97%,表明方法具有较好的准确度和精密度。按照本方法测定大虾国家标准物质(GBW10050),测量值均在标准值范围内。结论该方法快速、准确、灵敏度高,适合大批量样品的分析。     

微波消解-电感耦合等离子体质谱法测定蔬菜中的重金属

目的建立测定蔬菜中砷、铅、镉、汞、铜多元素的电感耦合等离子体质谱法。方法样品经微波消解后,采用电感耦合等离子质谱法进行测定,选择~(45)Sc、~(72)Ge、~(115)In、~(209)Bi作为内标元素补偿基体效应,优化仪器参数,对该方法的检出限、线性范围、精密度和回收率进行考察,并对市售的8种蔬菜样品中5种元素同时进行测定。结果研究结果表明,砷、铅、镉、汞、铜5种元素线性关系良好,相关系数均大于0.995,检出限为0.001~0.05 mg/kg,相对标准偏差低于1.5%,不同样品基质加标回收率在82.5%~109.9%范围之间。结论本方法快速、灵敏、准确,适用于蔬菜中砷、铅、镉、汞、铜5种元素的同时测定。     

MAE-GC/MS法测定食品中B(α)P

建立了测定食品中苯并芘(B(α)P)含量的MAE-GC/MS法。样品经微波辅助萃取技术前处理,DB-5MS弹性石英毛细管柱(30 m×0.25 mm×0.25μm)分离,以B(α)P m/z=252为选择离子,串连四极杆选择离子检测模式检测,再以9-苯基蒽为内标,采用内标法定量。结果显示,B(α)P的检出限为0.01μg/kg,标准曲线线性范围为0~10μg/m L,相关系数为1.000,方法回收率达97%~103%;精密度良好:日内RSD0.5%,日间RSD1%;准确度良好:以阴性样品为基底物质,在0.1 m L甲醇苯并芘成分分析国家标准物质(GBW08702)的加标水平上,测定值在其标准值范围内。表明:该法前处理简单,回收率高,检出限、线性范围、准确度、精密度结果均满足要求,可用于测定食品中的B(α)P含量。     

微波消解-电感耦合等离子体质谱法测定油茶籽油中的5种重金属元素

建立微波消解-电感耦合等离子体质谱法测定油茶籽油中的Pb、Cd、Cr、Cu、As五种重金属元素的方法。优化微波消解条件和仪器测定条件,选择同位素187Re、103Rh、45Sc作为内标元素来校正基体带来的干扰。方法的检出限在0.36～1.64μg/kg,加标回收率在84%～111%之间,精密度RSD在1.6%～7.6%(n=5)之间。采用该方法对茶叶标准样品(GBW10016)和苹果标准样品(GBW10019)进行验证,测定值均在保证值范围内。本方法具有快速、准确、可靠、灵敏度高。     

ICP-MS法同时测定天然矿泉水中12种元素的研究

该文建立了一种同时测定天然矿泉水中12种元素的电感耦合等离子体质谱(ICP-MS)法。对样品的前处理方法进行优化,并通过动能歧视(KED)模式和在线加入内标溶液消除相关干扰。方法检出限为0.03~0.1ng/m L,加标回收率为94.8%~104.9%,RSD值为0.12%~1.91%,相关系数r为0.9999~1.000。该方法简便快捷,应用范围广,准确度和精密度较高,可重复性较好,满足天然矿泉水中12种元素含量的测定要求,为天然矿泉水的质量安全监督和管理提供参考依据。     

微波消解-火焰原子吸收光谱法测定三峡库区鲤鱼中4种重金属元素

建立鲤鱼中4种重金属元素的微波消解-火焰原子吸收测定的方法。利用微波消解处理鲤鱼样品,使用火焰原子吸收光谱方法测定鲤鱼中Pb、Cd、Cu和Cr的含量。结果显示,鲤鱼中Pb、Cd、Cu和Cr含量分别为0.361、0.153、5.860、1.273μg/g,除Cd以外,均在国家限量范围之内;方法检测线为0.01~0.12μg/g,精密度试验RSD为1.74%~4.56%,重复性试验RSD为2.89%~5.76%,加标回收率为94.1%~121.5%;与国标检测方法相比,该方法检测速度快、精密度高。因此,该测定方法操作简单、速度快,灵敏准确,可用于三峡库区鲤鱼中4种重金属元素的测定。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

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.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

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.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<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     

Chinese CTP Market

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%.     

Preparatory Work of Print China 2015 is Going Smoothly

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