分散固相萃取—超高效液相色谱—串联质谱法测定液态奶中11种农药残留量

目的：评估液态乳中农药残留量的安全性。方法：建立同时测定11种农药残留的超高效液相色谱—串联质谱法。待测样品经乙腈提取，C₁₈和PSA固相萃取剂净化，经色谱柱Xbridge BEH C₁₈ （100 mm×2.1 mm，1.7 μm）分离，多反应监测模式进行测定，并使用响应曲面法优化前处理参数。结果：前处理的最佳条件为乙腈用量10 mL，C₁₈用量50 mg，PSA用量30 mg。11种农药在1.0~100.0 μg/L的浓度范围内线性关系良好，相关系数（R²）均＞0.999。在10，20，100 μg/kg添加水平内，11种农药的平均回收率为82.7%~102.0%，相对标准偏差为2.89%~8.87%，检出限和定量限分别为2.0~3.0，5.0~10.0 μg/kg。结论：该方法操作简便，分析时间短，回收率高，重现性好，能够准确定性定量分析液态乳中11种农药残留量。     

高效液相色谱-串联质谱法测定液体乳中氯酸盐和高氯酸盐

建立了液体乳中的氯酸盐和高氯酸盐高效液相色谱－串联质谱法的测定方法,样品经0.2%甲酸水－甲醇(10：90, v/v)提取,HLB固相萃取柱净化。经AcclaimTRINITYP1复合阴离子交换柱(100mm×2.1mm,3μm)洗脱。在流速 0. 5 mL/min下以乙腈－20mmoL/L甲酸铵溶液(70∶ 30,V/V)作为流动相,梯度分离。采用三重四极杆电喷雾离子源(ESI源)电离－多反应监测(MRM)－负离子监测模式检测,分别以氯酸根－_¹⁸O₃高氯酸根－_¹⁸O₄为内标物。进行内标法定量。氯酸盐和高氯酸盐分别在 0.0 ～50. 0 μg/kg和0.0 ～25. 0 μg/kg范围内线性关系良好,相关系数R_²都大于0.999。方法的测定低限分别为1.2μg/kg和1.0 μg/kg.回收率为80.6%～93.6%,RSD值为2.14%～6.68%,实验表明该方法提取率高,准确可靠,适用于液体乳中氯酸盐和高氯酸盐的定量分析。     

高压离子色谱法快速测定水中7种无机阴离子

目的：建立高压离子色谱法快速测定水中氟离子、亚氯酸根离子、氯离子、硝酸根离子、氯酸根离子、溴离子、硫酸根离子7种无机阴离子含量的方法。方法：选用Dionex Integrion高压离子色谱仪和Ionpac AS19色谱分析柱，KOH淋洗液浓度为20 mmol/L、流速为2.00 mL/min条件下，通过抑制型电导检测器测定水中7种无机阴离子含量。结果：7种无机阴离子在7 min内实现分离，该方法的线性相关系数≥ 0.999，相对标准偏差＜2%，7种阴离子的样品加标回收率为95.3%~105.8%。结论：该方法具有简便快速、准确灵敏、环保高效等优点，适用于水质分析中7种无机阴离子的同时快速测定。     

离子色谱法测定糖蜜样品中氯离子、硫酸根和硝酸根含量

目的 建立离子色谱法测定糖蜜样品中氯离子、硫酸根离子和硝酸根离子含量的方法。方法 使用去离子水对样品进行准确定容的稀释,之后对稀释后样品溶液过IC Na柱净化后上机测定样品的氯离子、硫酸根和硝酸根含量。使用Ion Pac _^TMAS19(4 mm × 50 mm)为分析柱,KOH淋洗液的浓度为35.0 mmol/L,流速1.0 mL/min,进样体积50 μL,外标法定量。结果 氯离子、硫酸根、和硝酸根标准溶液在0.05 ~ 2.0 mg/L浓度范围内呈现良好线性关系,R_²大于0.99,检出限0.02 ~0.1mg/L。在1.0 ~ 4.0 mg/L添加浓度上,回收率范围为85.4%~102.6%,相对标准偏差3.63%~10.64%。结论 该方法操作简便且快速准确,能够有效测定糖蜜中的氯离子、硫酸根和硝酸根含量,满足糖蜜中氯离子、硫酸根和硝酸根的检测需求以及样品的分析测定。     

离子色谱法测定昌都市江水中5种阴离子

建立了离子色谱法-电导检测器同时测定扎曲、昂曲与澜沧江水中F~-,Cl~-,Br~-,NO_3~-及SO_4~(2-)等5种阴离子。采用Dionex Ion Pac AS19分离柱和Ion Pac AG19保护柱,在16 min内完成阴离子分离和检测。分析条件:淋洗液为20 mmol/L KOH,流速为1.0 mL/min,柱温为30℃。阴离子的定性限和定量限分别为0.5~3.8μg/L和1.7~12.7μg/L,线性相关系数在0.999 0以上,氟离子、氯离子、溴离子、硝酸根和硫酸根回收率范围分别为97.1%~107.5%,91.3%~103.9%,97.4%~103.2%,94.8%~100.6%和93.8%~103.3%,相对标准偏差均小于3%(n=7)。该方法准确度好、精密度高、快速,适用于检测扎曲、昂曲与澜沧江水中5种阴离子含量。     

HPLC-MS/MS法测定烟用纸张中的高氯酸根

为快速、准确测定烟用包装材料中的高氯酸根,建立了测定烟用纸张(接装纸、内衬纸、条与盒包装纸)中高氯酸根离子的高效液相色谱-串联质谱(HPLC-MS/MS)方法。样品经水提取、多级固相萃取柱净化后,采用阴离子分析柱,以乙腈-乙酸铵水溶液为流动相进行色谱分离,在多反应监测(MRM)模式下进行质谱测定。结果表明:1~(18)O标记高氯酸根离子内标的加入及样品的多级净化有效降低了基质效应;2在0.2~20.0μg/L质量浓度范围内,标准曲线线性关系良好(R20.995);加标回收率为95.2%~105.5%;日内和日间相对标准偏差均8%;检出限和定量限分别为1.13和3.77μg/kg。3在所测定的100个样品中,高氯酸根离子的检出率为9%,最高检出量为0.048 mg/kg,远小于美国食品药品监督管理局(US FDA)所规定的食品包装材料中允许的最高限量。该方法操作简便、灵敏度高、准确性好,适用于烟用纸张中高氯酸根离子的测定。     

超高效液相色谱-串联质谱法测定聚氯乙烯食品接触材料中3种柠檬酸酯增塑剂

目的 建立超高效液相色谱-串联质谱法测定聚氯乙烯食品接触材料中3种柠檬酸酯类增塑剂的方法。方法 采用正己烷/二氯甲烷（1∶1，V/V）提取，经硅胶固相萃取柱净化，乙腈/乙酸乙酯（1∶4，V/V）洗脱，进入UPLC-MS/MS分析，以乙腈和超纯水做流动相，经BEH C₁₈色谱柱（2.1 mm×50 mm，1.7 μm）分离，采用ESI源在MRM正离子模式下检测，外标法定量。结果 3种化合物在线性范围内决定系数R²>0.996，方法检出限0.1~0.6 μg/kg，定量限0.3~2.2 μg/kg，回收率为70.3%~103.1%，相对标准偏差为0.9%~9.8%。结论 该方法分析快速、灵敏、准确，适用于塑料材料中柠檬酸酯类增塑剂含量的检测，为新型增塑剂的添加使用监管提供方法。     

盐析辅助液液萃取-HPLC-MS/MS法检测液态乳中13种双酚类和烷基酚类物质

目的:建立盐析辅助液液萃取-HPLC-MS/MS法同时检测液态乳中13种双酚类和烷基酚类化合物的方法。方法:采用盐析辅助液液萃取前处理方法,三重四极杆质谱负离子源多反应监测(MRM)模式下进行检测,基质外标法定量分析;研究萃取溶剂种类、盐析助剂的选择和用量对回收率的影响;并评估方法性能。结果:以乙腈为提取溶剂、0.4 g氯化钠为盐析助剂对液态乳进行液液萃取,13种酚类物质线性关系良好,相关系数均＞0.99;牛奶和酸奶中的加标回收率分别为81.5%~118.1%和80.8%~107.6%,相对标准偏差分别为1.89%~12.3%和1.12%~11.9%;方法检出限为0.15~0.75μg/kg,定量限为0.5~2.5μg/kg。市售液态乳样品中有1个样品检出含有4-NP,含量为9.28μg/kg。结论:试验所建方法适合液态乳中13种双酚类和烷基酚类化合物的快速检测。     

QuEChERS-UPLC-MS/MS测定大米中氯虫苯甲酰胺和五氟磺草胺的残留

目的：建立一种新的QuEChERS-超高效液相色谱—串联质谱（UPLC-MS/MS）检测大米中氯虫苯甲酰胺和五氟磺草胺的残留方法。方法：样品经0.2%甲酸—乙腈提取后，N-丙基乙二胺（PSA）和石墨化碳黑（GCB）填料净化，以0.2%甲酸水—乙腈为流动相梯度洗脱，经C₁₈色谱柱分离，采用UPLC-MS/MS测定。结果：氯虫苯甲酰胺和五氟磺草胺的定量限（LOQ）均为0.004 mg/kg，方法检出限（LOD）均为0.001 mg/kg。两种待测农药在0.002~0.5 mg/L质量浓度范围内呈良好的线性关系，其相关系数均在0.993以上。在0.05，0.1，0.5 mg/kg添加水平下，两种待测农药的平均回收率为86%~110%；相对标准偏差（RSD）为1.5%~6.1%。结论：该方法高效简便、稳定性好、灵敏度高，适用于大米中氯虫苯甲酰胺和五氟磺草胺的检测。     

液相色谱—串联三重四极杆复合线性离子阱质谱法测定水生蔬菜中45种抗生素

目的:建立超高效液相色谱—三重四极杆复合线性离子阱质谱法同时测定水生蔬菜中多种抗生素类化合物。方法:样品以含0.1%甲酸的乙腈溶液为溶剂,加入N-丙基乙二胺(PSA)、无水Na₂SO₄和C₁₈净化处理,质谱采用分时段多反应检测—信息关联—增强子离子(SMRM-IDA-EPI)扫描模式及谱库检索技术,通过对化合物保留时间、离子对及EPI谱库检索对比,外标法定量。结果:45种抗生素在1.0~100.0 μg/L质量浓度范围内线性关系良好(R²＞0.99),检出限为0.3~1.0 μg/kg,定量限为1.0~3.0 μg/kg,在3个浓度添加水平下,45种抗生素的回收率为60.4%~121.7%,相对标准偏差为0.9%~10.2%。结论:该方法快速简便、定性能力强,适用于水生蔬菜中45种抗生素类化合物的筛查确证和定量检测。     

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