超高效液相色谱-串联质谱法测定茶叶中6种农药残留

目的建立超高效液相色谱-串联质谱法测定茶叶中吡虫啉、多菌灵、啶虫脒、水胺硫磷、三唑磷和甲基异柳磷6种农药残留的方法。方法样品经乙腈提取,NH_2固相萃取小柱富集、净化,以二氯甲烷-甲醇(9:1,V:V)为洗脱溶液;样品经浓缩定容后,采用Thermo C_(18)(2.1 mm×50 mm,1.7μm)色谱柱分离,流速为0.3 mL/min,以水-甲醇-乙腈为流动相进行梯度洗脱,采用超高效液相色谱-串联质谱法多反应监测模式进行测定,采用基质标准溶液外标法定量。结果 6种农药在0.005~0.25μg/mL浓度范围内呈良好的线性关系,相关系数为0.9973~0.9998。当添加水平为0.005、0.025、0.25 mg/kg时,6种农药在茶叶中的加标回收率为72.4%~106.6%,相对标准偏差为1.6%~10.0%。方法定量限为0.5~5μg/kg。结论该方法操作简单、快速,可适用于茶叶中吡虫啉、啶虫脒、多菌灵、水胺硫磷、三唑磷和甲基异柳磷6种农药残留的测定。     

气相色谱-三重四极杆串联质谱法对甜瓜中11种农药残留的测定

目的建立用气相色谱-串联质谱联用法检测甜瓜中甲胺磷等11种农药残留的分析方法。方法样品用QuEChERS法提取,经MgSO_4、PSA净化,气相色谱-串联质谱法测定,外标法定量。结果 11种农药在添加浓度为0.05、0.10、0.20 mg/kg水平时具有良好的线性关系,相关系数均大于0.991,回收率为80.10%~111.30%,相对标准偏差(relative standard deviation,RSD)范围为1.32%~11.00%,检出限在0.0003~0.01 mg/kg。结论该方法简便、快捷,准确性、精确性和灵敏度均满足农药残留分析的要求。     

SPE-GC-MS/MS法测定茶叶中49种农药残留

建立固相萃取-气相色谱-三重四极杆串联质谱法测定茶叶中49种农药残留的分析方法。样品经乙腈均质提取,经ENVI-Carb+Florisil固相萃取小柱进行净化后,采用气相色谱-三重四极杆串联质谱法在多反应监测(MRM)模式下测定,外标法定量。49种农药成分在10μg/L~100μg/L范围内有良好的线性关系,相关系数在0.995 2~0.999 9范围内;49种农药成分在3个添加水平下(10、50、100μg/L),加标回收率范围为71.43%~115.21%,RSD(n=6)为1.13%~11.05%;各农药成分的检出限均小于1.06μg/kg。该方法样品处理简单快速,灵敏度和选择性高,适用于日常检测工作。     

液相色谱串联质谱法同时检测茶叶中23种农药残留

建立了Qu ECh ERS样品前处理-液相色谱串联质谱法同时检测茶叶中23种农药残留的分析方法。样品经Qu ECh ERS方法进行前处理,采用液相色谱分离、多反应监测(MRM)模式进行检测,基质曲线外标法定量。23种农药的定量限(LOQ)为0.09μg/kg~10μg/kg,多菌灵和杀螟硫磷线性范围为5.0 ng/m L~80 ng/m L,其他农药线性范围为2.0 ng/m L~40 ng/m L,线性相关系数均大于0.992 5。多菌灵和杀螟硫磷在20、40、80μg/kg 3个添加水平、其他21种农药在10、20、40μg/kg 3个添加水平范围内的回收率为67%~115%,相对标准偏差(RSD)为1.3%~14.8%。该方法操作简便、灵敏度高,适合于茶叶中23种农药残留的定量及确证分析。     

PRiME HLB固相萃取柱结合气相色谱-串联质谱法快速测定茶叶中200种农药残留

目的 建立PRiME HLB固相萃取柱结合气相色谱-串联质谱法(gas chromatography-tandem mass spectrometry,GC-MS/MS)快速测定茶叶中200种农药残留量的分析方法.方法 样品用乙腈提取,经PRiME HLB通过式固相萃取柱净化,残留量采用气相色谱-串联质谱法进行检测.结...     

改进的石墨烯分散固相萃取-液相色谱-串联质谱法测定茶叶中15种氨基甲酸酯类农药的残留量

目的以石墨烯为吸附剂,建立分散固相萃取-液相色谱-串联质谱法测定茶叶中多种氨基甲酸酯类农药残留量。方法样品采用水浸泡、乙腈提取,石墨烯作为吸附剂祛除杂质后,液相色谱-串联质谱仪测定,外标法定量。结果 15种氨基甲酸酯类农药在0.001~0.02μg/mL范围内线性良好,相关系数均大于0.990,且定量限均可达到0.01 mg/kg。空白样品在0.01、0.02和0.10 mg/kg 3个添加水平下,回收率范围为61%~106%,相对标准偏差为4.6%~13%。结论本方法操作简便、快速、成本较低,适用于茶叶中氨基甲酸酯类农药的检测。     

GC-MS/MS法测定铁皮石斛中19种农药残留

建立固相萃取-气相色谱-三重四极杆串联质谱法测定铁皮石斛中19种农药残留的分析方法。石斛样品经乙腈提取,经ENVI-Carb/Florisil固相萃取小柱进行净化后,采用气相色谱-三重四极杆串联质谱法在多反应监测(MRM)模式下测定,外标法定量。19种农药成分在10μg/L~200μg/L范围内有良好的线性关系,相关系数在0.993 1~0.999 8范围内;19种农药成分在3个添加水平下(10、100、200μg/L),加标回收率范围为82.83%~109.29%,RSD%(n=5)为1.43%~5.74%;各农药成分的检出限均小于0.58μg/L。该方法可应用于石斛中多种农药残留的同时检测。     

QuEChERS结合高效液相色谱-串联质谱法测定大白菜中10种喹诺酮类药物残留

摘 要: 目的 建立QuEChERS结合高效液相色谱-串联质谱法测定大白菜中10种喹诺酮类药物残留的检测方法。方法 大白菜样品经提取,采用QuEChERS净化方法,以诺氟沙星-D5为内标,用高效液相色谱-串联质谱法测定,采用正离子电喷雾,多反应监测模式（multiple reactions monitoring, MRM),内标法定量分析10种喹诺酮类药物残留的含量。结果 10种喹诺酮类在5~100 ng/mL的浓度范围内线性良好,检出限为0.1~0.3 μg/kg,定量限为0.3~1.0 μg/kg,平均回收率为76.0%~107%,相对标准偏差为1.5%~8.1%。 结论 本研究建立的QuEChERS结合高效液相色谱-串联质谱法测定大白菜中10种喹诺酮类药物残留的检测方法准确、可靠, 适用于大白菜中喹诺酮类药物残留的检测。     

超高效液相色谱-串联质谱法快速筛查茶叶中的多种农药残留

目的采用超高效液相色谱-串联质谱技术(UPLC-MS/MS)和改进的Qu ECh ERS样品前处理技术,建立茶叶中多种农药残留的快速筛查检测方法。方法样品采用乙腈提取,提取液经N-丙基乙二胺(PSA)、石墨化炭黑(GCB)及茶叶农残检测专用吸附剂(TPT)混合进行分散固相萃取净化(d-SPE)。以BEH C18色谱柱(2.1 mm×100 mm,1.7μm)进行色谱分离,以电喷雾电离串联质谱多反应监测模式(MRM)进行监测。结果以欧盟农药残留参比实验室组织的茶叶中175种农药残留的国际比对考核的茶叶样品进行定性筛查和定量测定,以液相色谱质谱技术从考核茶叶样品中共定性筛查出多菌灵、吡虫清、噻嗪酮等10种农药残留。针对这10种农药进行了定量检测方法的建立和方法验证,10种农药在0.1~20μg/L的浓度范围内呈良好线性,相关系数r0.999,各农药的定量限为0.5~2.0μg/kg,茶叶样品基质的加标回收率在75.7%~105.8%之间,相对标准偏差在2.3%~18.4%之间。定量测得考核的茶叶样品中10种农药的含量在0.021~0.373 mg/kg之间。结论本方法简单、准确、灵敏度高,适用于农产品中农药多残留的快速筛查。     

QuEChERS-超高效液相色谱-串联质谱法测定茶叶中47种农药残留

建立一种QuEChERS-超高效液相色谱-串联质谱法同时测定茶叶中47种农药残留的分析方法。样品经1%乙酸乙腈提取,QuEChERS方法净化,配有电喷雾离子源（ESI±）的超高效液相色谱-串联质谱（UPLCMS/MS）,在正负离子多反应监测（MRM）模式下同时测定,基质匹配外标法定量。结果表明：47种目标化合物在一定范围内线性关系良好,相关系数（r）为0.9971～0.9996,检出限为0.001～0.006 mg/kg,定量限为0.002～0.020 mg/kg,平均回收率为73.4%～114.3%,相对标准偏差（n=6）为0.3%～19.9%。该方法灵敏、准确、稳定,可满足茶叶中47种农药残留的检测要求。     

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