Florisil固相萃取-气相色谱法测定蜂蜜中的六六六、滴滴涕残留量

目的建立Florisil固相萃取-气相色谱法测定蜂蜜中六六六(hexachlorocyclohexane,HCH)、滴滴涕(dichlorodiphenyl trichloroethane,DDT)残留量的分析方法。方法样品加水后利用乙腈提取残留农药,选用Florisil柱中加入乙二胺-N-丙基硅烷(primary secondary amine,PSA)为净化材料,以固相萃取方法净化样品,以DB-17石英毛细管色谱柱分离,采用气相色谱-电子捕获检测器测定,以峰面积外标法定量。结果 8种农药在3个添加水平下的平均回收率在70.2%~97.4%之间,相对标准偏差为1.2%~9.6%,方法检出限为0.00006~0.0004 mg/kg,均能达到农残分析的要求。结论该方法具有操作简便、快速、准确的特点,适用于蜂蜜中六六六、滴滴涕残留的分析。     

高效萃取吸管-在线凝胶色谱-气相色谱-质谱法测定淡水鱼中的农药残留量

目的 建立一种在线凝胶色谱-气相色谱-质谱(gel permeation chromatography coupled with gas chromatography-mass spectrometry, GPC-GC/MS)联用法测定淡水鱼中农药残留的检测方法。方法 采用超声辅助技术和高效萃取吸管法对南昌地区淡水鱼样品净化处理, 以乙腈为提取液, 采用氯化钠去除水分后, 经在线GPC-GC-MS系统进样分析, 选择离子检测方式定量检测。结果 25种化合物的质量浓度在一定范围内与其对应的峰面积有良好的线性关系, 相关系数大于0.996, 方法的检出限为9.1×10?5~3.1×10?1 mg/kg。以空白样品为基体进行加标回收实验, 回收率为71.4%~103.2%, 相对标准偏差小于9%。结论 该方法前处理简单快速, 灵敏度高, 有机溶剂使用量少, 适用于淡水鱼中农药残留的检测。     

测定茶叶中27种有机氯和拟除虫菊酯农药多组分残留气相色谱法

为了更有效地对我国茶叶的质量和安全性进行监管,建立了一种快速测定茶叶中20种有机氯和7种拟除虫菊酯农药多残留的气相色谱法。试样中农药残留在超声波振荡条件下用乙腈提取,提取液经氮气流浓缩和Florisil固相萃取小柱净化,用气相色谱-电子捕获检测器测定,色谱柱为HP-5小口径石英毛细管柱(30m×0·32mm×0·25μm)。农药的添加水平在6·0~228μg/kg范围时,在绿茶中的平均添加回收率为71·2%~115%,相对标准差为3·42%~18·9%;在花茶中的平均添加回收率为71·1%~121%,相对标准差为3·55%~19·2%。方法的检测限范围为0·12~6·0μg/kg。该方法快速、灵敏、准确、成本低,能满足农药多残留快速扫描的分析要求。     

固相微萃取-气相色谱-串联质谱法快速筛查葡萄酒中农药残留

目的建立固相微萃取-气相色谱-串联质谱法快速筛查检测葡萄酒中农药残留。方法葡萄酒样品稀释后进行固相微萃取,直接进行气相色谱-串联质谱检测。优化选择了萃取纤维类型、萃取方式、萃取时间等固相微萃取的实验条件,考察了方法性能(检出限、添加回收率和精密度等)。结果确定方法可检测目标农药为94种,其检出限10μg/L,平均回收率在60%~110%之间,且方法的重复性和再现性标准偏差分别在20%和30%之内。结论该检测方法操作简便、快速,单个样品分析时间不超过1 h,适用于葡萄酒中农药残留的快速筛查检测。     

小麦粉中12种有机磷农药残留量测定的研究

报道了毛细管气相色谱法测定面粉中12种有机磷农药残留量的方法。采用丙酮提取,二氯甲烷萃取,浓缩后以乙腈定容。经石英毛细管气相色谱柱DB-1701(30m×0.25mm×0.25μm)分离,火焰光度检测器检测,外标法定量。结果表明,农药在小麦粉中的加标回收率为81.8%～113.1%,相对标准偏差为2.5%～11.8%,方法的检出限为0.0007～0.0037mg/kg,符合农药多残留测定技术的要求。     

麦芽中有机氯及拟除虫菊酯类农药残留的检测方法

本文建立了啤酒原料麦芽中13种有机氯及拟除虫菊酯农药的提取、净化和气相色谱检测方法。麦芽用乙腈萃取,采用Florisil小柱净化,采用GC—ECD检测。该方法对α－六六六、β－六六六、γ－六六六、δ－六六六、七氯、艾氏剂、狄试剂、OP′DDD、PP′DDD、OP′—DDT、PP′—DDT、甲氰菊酯、溴氰菊酯等13种有机氯及拟除虫菊酯农药的回收率在62％～97％。相关系数〉0．99。     

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。     

顶空-液相微萃取在烟用香精分析中的应用

考察了萃取溶剂、萃取剂体积、样品预平衡时间、萃取时间以及萃取温度对顶空-液相微萃取(HS-LPME)的影响,建立了XJ1香精样品的HS-LPME前处理方法,即样品在室温(20℃)下预平衡20min后,用2μL正丙醇顶空萃取20min,并采用GC法分析了HS-LPME萃取液中的挥发性组分。结果表明,XJ1香精中6种挥发性组分:柠檬烯、6-甲基-5-庚烯-2-酮、苯甲醛、芳樟醇、苯甲醇和2-乙酰吡咯的回收率在86.3%～107.7%之间;相对标准偏差(RSD)<4.32%;检出限达0.16～3.02μg/mL。HS-LPME适用于XJ1香精挥发性组分的快速分析。     

液液萃取-气相色谱-质谱联用快速检测葡萄酒中 14 种农药残留

建立了葡萄酒中 14 种农药残留的气相色谱-质谱联用选择离子模式进行监测的检测方法,样品采用正己烷:乙酸乙酯(1:1)萃取,无需净化。该方法在 0.01～10 mg/L 范围内线性关系良好,相关系数大于 0.998;在 0.01～1.0 mg/L 添加水平范围内,平均加标回收率在90.32～108.13 之间;最低检出限(LOD)0.01～0.10 mg/kg 之间,定量检出限(LOQ)为 0.001～0.05 mg/kg,相对标准偏差均小于 10 %。     

毛细管气相色谱测定小麦粉中过氧化苯甲酰方法的改进

对GB/T 18415-2001《小麦粉中过氧化苯甲酰的测定方法》中的方法2进行了改进。小麦粉通过酸性石油醚（60－90℃）萃取,过氧化苯甲酰转化为苯甲酸,样品和萃取剂的使用量按比例减少,具塞三角瓶改为具塞玻璃试管,旋荡时间缩短一半,经石英毛细管柱HJRT柱分离,氢火焰离子化检测器检测,以外标法定量分析。此方法的相对标准偏差为1.7%－3.6%,线性范围为0.01－0.1 g/L（r=0.998）,检出限为10－12 g/s,回收率为97.2%-98.8%。     

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