液相色谱-三重四级杆质谱法测定苹果中 腈苯唑农药残留

目的 为加强我国苹果中腈苯唑农药残留的监控,保护我国苹果在国际贸易中的合理地位,建立了苹果中腈苯唑的液相色谱-三重四极杆质谱(UPLC-MS/MS)测定方法。方法 样品经乙腈提取,超高效液相色谱-串联质谱下进行测定。结果 目标物在0.005~0.50 mg/L范围内成线性,相关系数r>0.99,空白样品中分析物在添加浓度为0.01、0.02、0.05 mg/kg时,平均回收率为89.6%~93.0%,相对标准偏差为2.4%~7.9%,定量限为0.01 mg/kg。结论 本方法操作简便、灵敏度高、准确度好,能满足农残检测分析的要求。     

液相色谱-三重四级杆质谱法测定苹果中腈苯唑农药残留

目的为加强我国苹果中腈苯唑农药残留的监控,保护我国苹果在国际贸易中的合理地位,建立了苹果中腈苯唑的液相色谱-三重四级杆质谱(UPL-C-MS/MS)测定方法。方法样品经乙腈提取,超高效液相色谱.串联质谱下进行测定。结果目标物在0.005~0.50 mg/L范围内成线性,相关系数r0.99,空白样品中分析物在添加浓度为0.01、0.02、0.05 mg/kg时,平均回收率为89.6%~93.0%,相对标准偏差为2.4%~7.9%,定量限为0.01 mg/kg。结论本方法操作简便、灵敏度高、准确度好,能满足农残检测分析的要求。     

超高液相色谱串联质谱法检测土豆及土豆制品中α-茄碱

目的建立超高效液相色谱串联质谱法检测土豆及其制品中α-茄碱的分析方法。方法通过优化提取液,土豆样品经1%甲酸-甲醇(1:1,V:V)超声提取,采用BEH C_(18)色谱柱(2.1 mm×50 mm,1.7μm)分离,梯度洗脱,采用超高效液相色谱串联质谱法,在多反应监测模式进行定性和定量分析,而土豆淀粉用MCX固相萃取柱进行净化,液相色谱串联质谱法测定。结果土豆样品中回收率为75%~115%,相对标准偏差为5.0%~8.6%,土豆淀粉的回收率范围为67%~100%,相对标准偏差为3.4%~11.3%,方法的检出限和定量限分别为0.5 mg/kg和1.0 mg/kg。结论该方法适合于土豆及其制品中α-茄碱的分析。     

超高效液相色谱-串联质谱法测定苹果中刺糖菌素A

目的建立苹果中刺糖菌素A的超高效液相色谱-串联质谱(UPLC-MS/MS)测定方法。方法样品通过乙腈匀浆提取,在电喷电离方式(ESI+)、多反应监测模式(MRM)下进行测定,基质配标准曲线定量。结果分析物在0.005~0.50 mg/kg范围内成线性,相关系数r0.99,空白样品中分析物在0.01、0.02、0.10 mg/kg三个不同添加水平时,平均回收率在93.3%~101.7%之间,相对标准偏差为5.2%~7.4%,定量限为0.005 mg/kg。结论本方法灵敏度高、准确度好,能满足定量分析的要求。     

高效液相色谱法同时测定保健食品中11种功效成分

建立高效液相色谱同时测定保健食品中11种功效成分的高通量分析方法。样品前处理采用甲醇-水-磷酸溶液提取,对油脂样品则采用甲醇-水-磷酸溶液与正己烷液液萃取除脂。采用Agilent TC-C18色谱柱(250 mm×4.6 mm,5μm),乙腈-2 g/L辛烷磺酸钠溶液(加入1 m L磷酸)作为流动相,流速1.0 m L/min,梯度洗脱,用二极管阵列检测器串联荧光检测器检测,外标法峰面积定量。VB2在0.25~25 mg/L、VB6在0.5~20 mg/L、烟酸、烟酰胺在1~100 mg/L、其余5种功效成分在0.5~50 mg/L质量浓度范围内线性良好,相关系数r为0.999 1~1.000 0。在样品中待测成分含量约0.5、1倍和2倍3个水平的添加回收率为86.4%~110%之间,相对标准偏差为0.21%~11.7%。方法的定量限:烟酸、烟酰胺为20 mg/kg,其余9种功效成分方法的定量限为10 mg/kg。     

超高效液相色谱-串联质谱法测定茶叶中的百草枯

文章建立了一种利用超高效液相色谱-串联质谱法测定茶叶中百苹枯含量的方法.茶叶样品使用甲醇-0.1 mol/L盐酸溶液(3:7,V/V)提取,经Poly-sery MCX柱净化后用超高效液相液相色谱-串联质谱进行测定.在5～100μg/L浓度范围内,百草枯的线性良好(R2=0.9991),方法定量限为0.01 mg/kg...     

超高效液相色谱-串联质谱法测定干辣椒中2种新型杀虫剂残留量

目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定干辣椒中氰氟虫腙和氯虫苯甲酰胺残留量的分析方法。方法 干辣椒样品经乙腈匀浆提取, 氨基固相萃取小柱净化, 甲醇/水(50:50, V:V)定容, 以反相C18色谱柱(100 mm×2.1 mm, 1.7 μm)分离, 0.1%甲酸-水和甲醇作为流动相进行梯度洗脱, 多反应监测模式下进行超高效液相色谱-串联质谱测定、基质匹配标准溶液外标法定量。结果 2种新型杀虫剂在5~500 μg /L范围内线性关系良好, 相关系数均大于0.999, 定量限为0.008~0.01 mg /kg; 在高、中、低3个加标水平下的回收率为80.4%~94.9%, 相对标准偏差在0.9%~8.7%之间。结论 方法简单、快速、灵敏高、准确可靠, 可操作性强, 适合测定干辣椒中氰氟虫腙和氯虫苯甲酰胺残留量。     

高效液相色谱-串联质谱法测定油条中羧甲基赖氨酸

建立了利用高效液相色谱-串联质谱法(HILIC-HPLC-MS/MS)测定油条中羧甲基赖氨酸(CML)含量的检测方法。样品经硼氢化钠还原、盐酸水解,过混合型阳离子交换小柱萃取净化,样品溶液在HILIC色谱柱中以甲醇-水(均含2mmol/L乙酸铵和0.1%甲酸)为流动相进行梯度洗脱,CML被保留并与样品基质分离。选用电喷雾正离子(ESI+)模式电离,多反应监测模式(MRM)进行串联质谱分析。以内标法定量,D4-CML为内标物,分析时间为12min。本方法添加回收率范围89.5%~99.1%,相对标准偏差范围2.1%~2.6%,仪器检出限为1μg/L,定量限为3μg/L。应用该方法测得15种不同来源的油条中CML含量为69.3±8.2~182.2±3.1mg/(kg蛋白质),5.3±0.5~15.4±0.3mg/(kg样品)。本方法操作简便、快速、灵敏度高、精密度好,为进一步研究食品中CML的产生机理提供了有效的检测方法。     

UPLC-MS/MS法测定凉茶饮料中的有机酸和黄酮类化合物

建立一种超高效液相色谱-三重四级杆串联质谱法同时测定凉茶饮料中5种有机酸和黄酮类化合物的方法。样品经高速离心,甲醇稀释后,经BEH C18(100 mm×2.1 mm,1.7μm)色谱柱分离,乙腈-0.1%甲酸水(体积分数)梯度洗脱,串联质谱电喷雾负离子扫描,多反应监测(MRM)模式检测。5种目标物的方法检出限在0.2 mg/L~0.5 mg/L,在0.02 mg/L~0.5 mg/L浓度范围内,线性相关系数均大于0.999 0。添加水平为1.0 mg/L~40 mg/L时,平均回收率为86.3%~102%;相对标准偏差(RSD,n=6)为2.4%~8.7%。     

分散固相萃取-高效液相色谱串联质谱测定甘蓝及土壤中的啶虫脒

建立了甘蓝和土壤中啶虫脒的分散固相萃取-高效液相色谱串联质谱检测方法,该方法以1%乙酸乙腈为提取溶剂(1∶99,v/v),以无水硫酸镁(Mg SO4)、十八烷基键合硅胶(C18)和N-丙基乙二胺(PSA)富集净化,0.1%甲酸-水和甲醇梯度洗脱,C18柱分离,HPLC-MS/MS测定。方法线性范围0.01~2mg/L,相关系数为0.9994,定量限(LOQ)为0.01mg/kg。在0.05、0.5、1.0mg/kg加标浓度下,啶虫脒在甘蓝中的回收率为84.8%~107%,在土壤中的回收率为96.5%~115%,相对标准偏差小于10.92%。该方法能够满足甘蓝及土壤中啶虫脒残留限量检测要求。     

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