电感耦合等离子体质谱法测定预混矿物质中的碘

目的建立电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)测定预混料矿物质中碘元素。方法样品经5%氨水超声提取,通过电感耦合等离子体质谱仪,以103Rh作为在线内标,对样品溶液进行测定。结果在碘浓度为0～200μg/L的范围内,线性关系良好,线性方程为Y=8.173×10~(-4)X+1.991×10~(-4),相关系数r为0.9993。对预混料样品加入低、中、高3个梯度进行加标测定,回收率在88.6%～101.0%之间,相对标准偏差小于2.3%(n=3)。结论该方法准确、便捷、回收率良好,适用于不同预混料矿物质中碘含量的测定。     

婴幼儿配方乳粉中微量碘测定方法的比较

本文采用气相色谱法(GC)、电感耦合等离子体质谱法(ICP-MS)、离子色谱法(IC)分别测定了婴幼儿配方乳粉中碘的含量。通过多方面因素对比:前处理的方式、碘的测定种类、方法线性范围、回收率、检出限、精密度等,得出电感耦合等离子体质谱法前处理操作简便,受奶粉复杂基质干扰最小,在1~50μg/L线性范围内,相关系数可达到0.999以上。回收率在95.9%~103.7%之间,RSD为0.6%~2.2%,检出限为0.6μg/100g,最适合用于婴幼儿配方乳粉中微量碘的实验室常规分析。     

电感耦合等离子体-质谱法测定居民肉类膳食中碘的方法研究

建立测定肉类膳食中碘的电感耦合等离子体-质谱法(ICP-MS),并对我国14个省份居民肉类膳食进行测定。方法 样品用四甲基氢氧化铵-双氧水溶液在60℃超声提取3h,冷冻脱脂、甲酸沉淀蛋白后,以¹²⁸Te为内标元素,ICP-MS法测定肉类膳食中碘含量。结果 方法线性范围为1～200μg/L,r=0.9998,检出限2.3μg/kg,RSD≤5.7%(n=7),加标回收率为80.0%～96.6%。结论 该方法高效、可行,适用于肉类膳食中碘的测定,为居民肉类膳食中碘含量监测工作提供技术支持。     

电感耦合等离子体原子发射光谱法测定埋弧焊剂中磷含量

介绍电感耦合等离子体原子发射光谱法测定埋弧焊剂中磷含量,试验选择波长为178.284 nm,检出限为4.8μg/L,测得焊剂中磷回收率为99.2%～101.0%,相对标准偏差(样本数为6)小于2%,且与钼蓝光度法测定结果一致。电感耦合等离子体原子发射光谱法比化学方法具有更宽的线性范围和更低的检出限,更适用于焊剂中磷的测定。     

微波消解-电感耦合等离子体质谱法测定衢枳壳中17种微量元素的含量

目的建立微波消解-电感耦合等离子体原子发射光谱-质谱法测定衢枳壳药材中17种元素的分析方法。方法采用微波消解进行前处理,电感耦合等离子体原子发射光谱-质谱联用技术结合内标元素校正基体抑制效应,外标法定量。结果在0.5～500μg/L的浓度范围内,各元素有良好的线性关系,相关系数均大于0.999。各元素的检出限为2ng/L～1μg/L,加标回收率为67.3%～109%,相对标准偏差均小于15%。结论本研究建立的方法准确、可靠、灵敏度高,适用于衢枳壳基质中多元素测定。     

电感耦合等离子体质谱法测定海鱼中6种重金属含量

目的建立电感耦合等离子体质谱法测定海鱼中6种重金属的检测方法。方法样品用硝酸溶液微波消解进行前处理,采用电感耦合等离子体质谱法对样品中6种重金属进行测定。结果各元素在0~1.0 mg/L范围内呈良好的线性关系,相关系数均>0.999。方法检出限为铅:2.5μg/kg,镉:0.3μg/kg,汞:2.5μg/kg,砷:12.5μg/kg,铬:10μg/kg,镍:13μg/kg。回收率为92.4%~101%,相对标准偏差为2.1%~4.5%。结论该方法具有较高灵敏度、准确度及精密度,适用于海鱼中6种重金属元素的测定。     

ICP-OES/ICP-MS法测定罗汉果中46种元素

建立了电感耦合等离子体发射光谱(ICP-OES)/电感耦合等离子体质谱(ICP-MS)测定罗汉果中46种元素的方法。ICP-OES检出限在0.68~18.10μg/L之间,ICP-MS检出限在0.001~0.093μg/L之间。此方法的精密度(RSD)处于0.73%~6.83%之间,回收率介于88.7%~112.1%。国家标准物质灌木枝叶的检测结果与参考值基本相符。测定结果表明,罗汉果中含有丰富的微量元素,其中含量在2 mg/kg以上的达到13种。本方法快速灵敏,适用于罗汉果中多元素的同时分析。     

HPLC-ICP-MS法测定牛肝菌中汞的形态

建立高效液相色谱-电感耦合等离子体质谱联用测定牛肝菌中的无机汞、甲基汞、乙基汞形态的分析方法。采用微波萃取技术对样品进行前处理,并对液相色谱和电感耦合等离子体质谱的参数进行优化,结果表明:在优化条件试验下,3种汞化合物在1μg/L～20 0μg/L范围内线性关系良好,相关系数均大于0.999,方法的检出限在0.005 mg/kg～0.008 mg/kg之间,加标回收率在72%～93%之间,相对标准偏差(relative standard deviation,RSD)均小于7%。该方法前处理简单、检出限低、准确度高、耗时短,适用于牛肝菌中不同形态汞的筛查和测定。     

电感耦合等离子体质谱法测定锑的含量

通过采用电感耦合等离子体质谱法测定样品中锑的浓度含量,建立了一整套检验方法,包括预处理和结果分析。方法检出限(n=11,k=3)为0.09μg/L,精密度(n=7)为2.03%,回收率为95%～102%,线性良好,相关系数大于0.999。方法准确、可靠、快速,适用于日常检测。     

电感耦合等离子体质谱法测定食品接触材料中可溶性铅、镉、砷、汞

建立了食品用粘合剂、塑料瓶等高分子食品接触材料中可溶性铅、镉、砷、汞和含量的电感耦合等离子体质谱检测方法.样品中铅、镉、砷、汞的可溶部分溶解在0.07 mol/L的盐酸(模拟人体胃酸)中,·用电感耦合等离子体质谱检测,内标法定量.在0.5μg/L～100μg/L添加水平,回收率在88.6%～98.3%之间,精密度在1.8%～5.1%之间.     

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