搅拌棒萃取-气相色谱法检测大蒜及蒜粉中三唑磷残留

建立了搅拌棒萃取-气相色谱法检测大蒜及蒜粉中三唑磷农药残留。样品经搅拌棒萃取,解析液解析后,上机检测。采用Rtx-1701(30 m×0.25 mm×0.25 m)色谱柱分离,在程序升温的模式下检测,外标法定量。结果表明,三唑磷农药在质量浓度1.5~200μg/L范围内线性关系良好,相关系数r=0.998 3,方法的定量限为1.5μg/kg。在不同添加水平下,其平均回收率为71%~97%,变异系数为5.8%~10.8%。该方法简便、快捷,适用于大蒜及蒜粉中三唑磷的检测。     

搅拌棒萃取-GC-MS/MS法检测黑蒜汁中8种有机氯农药残留

建立了搅拌棒萃取-气相色谱法检测黑蒜汁中8种有机氯农药残留。样品经搅拌棒萃取,解析液解析后,上机检测。采用TR-5MS(30 m×0.25 mm×25μm)色谱柱分离,在程序升温的模式下检测,外标法定量。结果表明:8种有机氯在质量浓度0.01~1.0 mg/L范围内线性关系良好,相关系数R~2=0.990 3~0.998 6,方法定量限为0.01 mg/kg。在不同添加水平下,其平均回收率为73.7%~101.6%,变异系数为6.7%~11.5%。该方法简便、快捷,适用于黑蒜汁中有机氯农药残留的检测。     

分散固相萃取-分散液液微萃取-气相色谱-质谱联用法测定中草药类保健食品中29种有机磷农药残留

目的建立测定中草药类保健食品中有机磷农药残留的分散固相萃取-分散液液微萃取-气相色谱-质谱联用法。方法样品经含0.5%甲酸的乙腈超声提取,上清液经含无水硫酸镁、N-丙基乙二胺(PSA)、C18的分散固相萃取管(d-SPE)净化后,采用分散液液微萃取(DLLME)步骤,用氯仿萃取、浓缩目标化合物。结果在最优条件下,线性范围为0.05~1.00μg/ml,线性相关系数在0.999以上,检出限(LOD)为0.3~3.0μg/kg,29种有机磷农药的平均加标回收率在70.3%~107.5%之间,相对标准偏差均10%。结论该方法具有简便快速、准确灵敏、萃取效率高等特点,可用于中草药类保健食品中有机磷农药残留的检测。     

搅拌棒萃取-液质联用法检测大蒜中啶虫脒

建立搅拌棒吸附萃取结合液相色谱-串联质谱法检测大蒜中啶虫脒残留。样品经搅拌棒萃取,解吸液解吸后,上机检测。采用Hypersil GOLD-1.9μm,50 mm×2.1 mm(i.d)色谱柱分离,在选择反应监测模式下检测,外标法定量。啶虫脒在浓度0.005 mg/L~0.2 mg/L范围内线性关系良好,相关系数r=0.999 8,方法检测限为0.005 mg/kg。在不同添加水平下,其平均回收率为82.3%~92.2%,变异系数为7.73%~9.01%。该方法简便、快速,适用于大蒜中啶虫脒残留的批量检测。     

液相色谱-原子荧光法测定鱼肉中有机汞形态

建立微波辅助萃取-液相色谱-原子荧光(MAE-LC-AFS)测定鱼肉中甲基汞和乙基汞的分析方法。优化了液相色谱流动相、微博辅助萃取技术的提取剂浓度和萃取温度。在0~50μg/L范围内甲基汞和乙基汞的线性关系良好,线性相关系数大于0.999,甲基汞和乙基汞检出限(S/N=3)分别为0.07、0.13μg/L。3种样品在0.25、0.5、1.0 mg/kg 3个加标水平下的平均回收率为甲基汞80.3%~91.4%,乙基汞72.2%~83.3%,相对标准偏差(RSD)分别为2.4%~5.8%、2.3%~5.5%。该法适用于鱼肉中甲基汞和乙基汞的测定。     

气相色谱法测定蔬菜中8种有机磷农药的残留量

目的采用气相色谱法同时测定蔬菜中甲胺磷、氧化乐果、乐果、甲基对硫磷、毒死蜱、对硫磷、水胺硫磷和三唑磷8种有机磷农药的残留量。方法样品经乙腈提取后,经Agilent DB-17色谱柱分离,采用火焰光度检测器检测,以外标法定量。结果毒死蜱和乐果在0.25~5μg/m L,其他6种有机磷在0.025~0.5μg/m L浓度范围内具有良好的线性关系,检出限为0.006~0.023μg/m L;8种有机磷农药的回收率为97.6%~104.8%,相对标准偏差为0.98%~1.67%。结论该方法精确可靠,重复性、稳定性和分离效果好,可用于测定蔬菜中有机磷农药的残留量。     

搅拌棒萃取LC-MS/MS法检测大蒜中苯霜灵、扑灭津、哒螨灵及吡螨胺残留

建立了搅拌棒萃取(SBSE)结合液相色谱串联质谱法检测大蒜中苯霜灵、扑灭津、哒螨灵、吡螨胺4种农药残留。样品经搅拌棒萃取,解析液解析后,上机检测,采用Hypersil GOLD-1.9μm,50mm×2.1mm(i.d)色谱柱分离,在选择反应监测模式下检测,外标法定量。结果表明:四种农药在0.005-0.2mg/L浓度范围内线性关系良好,相关系数R2=0.9907-0.9985,方法检测限为0.005mg/kg。在不同添加水平下,其平均回收率为85.8-96.1%,变异系数为6.8-10.9%。     

毛细管SPE-GC法测定纺织品中邻苯二甲酸酯

建立了新型毛细管固相萃取-气相色谱法检测纺织品中邻苯二甲酸酯(PAEs)的方法。通过比较筛选出毛细管固相萃取柱的最佳萃取剂,并优化萃取条件,净化富集待测物质后与气相色谱联用进行定性定量检测。采用的毛细管内固相萃取条件为:选取C18中的萃取剂为毛细管固相萃取剂,1.2μL甲醇和1.2μL超纯水依次活化,上样速率0.5μL/min,热脱附。该方法在1~1 000μg/L质量浓度范围内线性关系良好;DMP、DEP和DBP的最低检出限分别是4.1μg/L、4.8μg/L和5.4μg/L;加标回收率分别是84%~99%、88%~97%和84%~98%;相对标准偏差(RSD)分别为5.34%、4.23%和6.02%。     

固相萃取－液相色谱－电喷雾串联质谱法测定鲜枣中14种农药残留

选择强疏水性硅胶基质t C18柱为固相萃取净化柱,以电喷雾(ESI)为离子源,正离子多级反应离子监测(MRM)模式,建立了固相萃取-液相色谱-串联质谱法(HPLC-MS/MS)测定鲜枣中14种农药(包括有机磷杀虫剂、杀菌剂,有机杂环类杀虫剂和新型烟碱类杀虫剂)残留的分析方法。研究比较了不同提取溶剂的提取效果和不同固相萃取小柱的净化效果,同时优化了色谱分离条件和质谱条件。14种农药在10~500μg/L(或1~50μg/L)范围内线性相关,相关系数为0.996 3~0.999 9,方法的定量限为0.10~9.50μg/kg。14种农药在鲜枣中3个水平添加质量浓度的的回收率在67.4%~116.8%,RSD为0.8%~14.8%之间。该方法操作简便,灵敏度、准确度和精密度均符合农药多残留检测技术要求,适用于鲜枣中14种农药多残留的检测。     

搅拌棒萃取-LC-MS/MS法检测大蒜中苯霜灵、扑灭津、哒螨灵及吡螨胺残留

建立了搅拌棒萃取(SBSE)结合液相色谱串联质谱法检测大蒜中苯霜灵、扑灭津、哒螨灵、吡螨胺4种农药残留。样品经搅拌棒萃取,解析液解析后,上机检测,采用Hypersil GOLD-1.9μm,50 mm×2.1mm(i.d)色谱柱分离,在选择反应监测模式下检测,外标法定量。结果表明:四种农药在0.005-0.2mg/L浓度范围内线性关系良好,相关系数R2=0.9907-0.9985,方法检测限为0.005mg/kg。在不同添加水平下,其平均回收率为85.8-96.1%,变异系数为6.8-10.9%。     

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