超高效液相色谱-串联质谱法测定茶叶中草甘膦和草铵膦的残留量

建立茶叶中草甘膦和草铵膦的残留超高效液相色谱法-串联质谱法快速检测方法。样品采用NaOH溶液提取后,HCl溶液调节酸度,经N-丙基乙二胺净化,氯甲酸（9-芴甲基）酯衍生化,正离子多反应监测测定,外标法定量。草甘膦和草铵膦在0.005～0.50 μg/mL质量浓度范围内线性关系良好,相关系数（r）均大于0.995,草甘膦和草铵膦的检出限均为0.05 mg/kg,定量限均为0.08 mg/kg,在添加量为0.08、0.10、1.0、2.0、4.0 mg/kg时,草甘膦的回收率为75.6%～95.5%,相对标准偏差为3.24%～8.38%（n=10）,草铵膦的回收率为76.0%～96.6%,相对标准偏差为3.05%～7.85%（n=10）。该方法样品前处理简单、分析时间短,回收率和精密度等均符合农药多残留检测技术的要求,适用于茶叶中草甘膦和草铵膦残留的同时检测。     

超高效液相色谱串联质谱法测定咖啡豆中草甘膦、氨甲基膦酸和草铵膦残留量

目的建立超高效液相色谱串联质谱法(ultraperformanceliquidchromat-ography/tandemmass spectrometry, UPLC-MS/MS)定量测定咖啡豆中草甘膦、氨甲基膦酸和草铵膦残留量。方法通过水提取样品,C18固相萃取小柱进行净化, FMOC-Cl溶液衍生,后采用超高效液相色谱串联质谱测定。结果草甘膦、氨甲基膦酸和草铵膦在2～100ng/mL范围内线性良好(r2≥0.999),方法的定量限为0.05mg/kg。在添加水平为0.05 mg/kg和0.5 mg/kg时,回收率为99.6%～107.6%,相对标准偏差低于4.52%。结论该方法准确、稳定、灵敏,能够满足咖啡豆中草甘膦、氨甲基膦酸和草铵膦检测与确证的需要。     

超高效液相色谱串联质谱法快速测定生活饮用水中草铵膦、草甘膦及其代谢物氨甲基膦酸残留

目的建立了一种非衍生-超高效液相色谱-串联质谱快速检测生活饮用水中的草铵膦、草甘膦及其代谢物氨甲基膦酸残留的方法。方法以5 mmol/L的乙酸铵-氨水溶液(pH 12.0)和乙腈为流动相,梯度洗脱,Dikma Polyamino氨基柱(2.0 mm×150 mm,5μm)色谱分离,采用电喷雾离子源负离子模式多反应监测(MRM)进行质谱测定,采用外标法定量。结果草铵膦、草甘膦、氨甲基膦酸分别在2.5～100,5～200,5～200μg/L的浓度范围内线性关系良好,相关系数(r~2)均大于0.999。方法的检出限分别为1.0、2.0、2.0μg/L,定量限为2.5、5.0、5.0μg/L。草铵膦、草甘膦、氨甲基膦酸在3档加标水平下的回收率为93.6%～102%,相对标准偏差(relative standard deviation,RSD)为4.47%～7.15%。结论本方法的样品无需衍生,简便、准确可靠,可用于生活饮用水中草铵膦、草甘膦及其代谢物氨甲基膦酸残留的快速检测。     

超高效液相色谱-四极杆/静电场轨道阱高分辨质谱法快速检测茶叶中草甘膦、草铵膦及其代谢物残留

摘 要：目的 建立一种非衍生化处理, 直接测定茶叶中草甘膦、草铵膦及代谢物的的快速分析方法。方法 茶叶样品经酸化的同体积甲醇-水进行提取, 经Oasis PRiME HLB 固相萃取柱通过式净化, 并通过超高效液相色谱-四极杆/静电场轨道阱高分辨质谱法对样品进行测定。结果 茶叶中草甘膦、草铵膦及代谢物在1.0~50 ng/mL的范围内, 线性关系良好(r2＞0.999), 平均回收率在83.7%~92.2%之间, 相对标准偏差低于10%, 检出限为0.01 mg/kg, 定量限为0.05 mg/kg。结论 此方法前处理简便快速, 且准确性好、灵敏度高, 可实现茶叶中草甘膦、草铵膦及其代谢物的快速筛查。     

分散固相萃取/衍生化-高效液相色谱-串联质谱法同时测定水和食品中草甘膦、草铵膦和氨甲基膦酸残留

目的建立高效液相色谱-串联质谱法测定水和食品中草甘膦、草铵膦和氨甲基膦酸的残留量。方法样品经纯水涡旋超声提取,二氯甲烷去除脂肪,C_(18)分散固相萃取净化,(水样)净化液在硼酸盐缓冲液中加入9-芴基甲基三氯甲烷(FMOC-Cl)丙酮溶液进行衍生化2 h以上,经0.22μm微孔滤膜过滤,经CAPCELLCORE C_(18)柱分离,用5 mmol/L乙酸铵溶液和乙腈为流动相梯度洗脱,采用电喷雾负离子多反应监测模式检测,外标法定量。结果草甘膦、草铵膦和氨甲基膦酸在0.5~40μg/L浓度范围内呈良好的线性关系(r0.999),方法定量限为0.5μg/kg。在0.5、5.0和20μg/kg添加水平时,平均回收率为70.1%~104.1%,相对标准偏差为0.6%~8.9%(n=6)。结论该方法分析速度快,净化效果好,杂质干扰小,回收率高,重复性好,适用于水和食品中草甘膦、草铵膦和氨甲基氨酸留量的测定。     

多壁碳纳米管分散固相萃取-液质联用技术测定茶叶中草甘膦、草铵膦、氨甲基膦酸残留量

目的建立茶叶中草甘膦、草铵膦和氨甲基膦酸残留量的超高效液相色谱串联质谱分析方法。方法样品经水提取后采用分散固相萃取技术,以多壁碳纳米管(MWCNTS)和N-丙基乙二胺键合固相吸附剂(PSA)吸附提取液中的杂质,上清液用9-芴基氯甲酸酯(FMOC-Cl)衍生。衍生物用BEH C18进行分离,以乙腈-4 mmol乙酸铵水溶液为流动相,电喷雾正离子模式电离(ESI+),多反应监测模式检测(MRM),外标法定量。结果方法的线性范围是0.1～1μg/mL,相关系数大于0.999,定量限为10μg/kg,以绿茶为基质,三种物质添加水平分别为0.25、0.50、1.00 mg/kg,回收率范围分别为草甘膦95%~116%,草铵膦98%~118%,氨甲基膦酸74%~84%,精密度均小于6.79%(n=6)。结论该方法具有简便快速、灵敏度高、准确性强等特点,适合于测定茶叶中草甘膦、草铵膦和氨甲基膦酸的含量。     

固相萃取净化液质联用测定茶叶中的草铵膦

建立了超高液相色谱-串联质谱法测定茶叶中草铵膦的方法。样品用水提取,先通过二氯甲烷萃取除去一部分杂质,再用固相萃取小柱(HLB)净化,以5 mmol·L~(-1)的乙酸铵-氨水溶液(pH 12.0)和乙腈为流动相,梯度洗脱,氨基柱色谱分离,采用电喷雾负离子模式和多反应监测模式测定,外标法定量。结果表明,草铵膦的线性范围为5～100μg·L~(-1),相关系数(R~2)均大于0.995。方法的检出限为0.02 mg·kg~(-1),定量限为0.05 mg·kg~(-1)。草铵膦在3个加标水平(50, 100和500μg·kg~(-1))下的回收率为77.6%～89.2%,相对标准偏差(RSD, n=6)为6.08%～8.54%。方法操作简单、快捷、有效、稳定,可满足茶叶中草铵膦的检测需求。     

QuEChERS-气相色谱-三重四级杆串联质谱法测定茶叶中草甘膦和氨甲基膦酸残留

建立气相色谱-三重四极杆质谱测定茶叶中草甘膦和氨甲基膦酸的分析方法。茶样经超纯水、二氯甲烷提取后,与三氟乙酸酐-七氟丁醇进行衍生反应,衍生后产物经乙二胺-N-丙基硅烷(PSA)、石墨化碳(GCB)、C18混合净化剂净化,TG-1701MS(30 m×0.25 mm,0.25μm)分离,气相色谱-串联质谱进行测定。试验详细考察了PSA、GCB、C18用量对草甘膦和氨甲基膦酸添加回收率的影响,结果表明,2 m L衍生液中加入50 mg PSA、25 mg GCB和25 mg C18时净化效果最好。在5μg/L~500μg/L范围内,草甘膦和氨甲基膦酸均有良好的线性关系(r20.999),定量限(LQD)(S/N=10)分别为0.03 mg/kg和0.015 mg/kg,样品加标浓度为0.50、1.00 mg/kg和2.50 mg/kg时,草甘膦的平均回收率为86.1%~101.2%,相对标准偏差(RSD)(n=6)为3.2%~6.7%;氨甲基膦酸的平均回收率为83.6%~103.4%,相对标准偏差(RSD)(n=6)为3.6%~7.3%。该方法样品前处理简单,分析时间短,回收率和精密度等均符合草甘膦和氨甲基膦酸检测技术的要求,适用于茶叶中草甘膦和氨甲基膦酸残留的检测。     

非衍生化液相色谱-串联质谱法测定茶叶中草铵膦残留量

目的 建立非衍生化液相色谱-串联质谱法直接测定茶叶中草铵膦残留的分析方法。方法 茶叶样品经水均质提取,HR-X固相萃取小柱净化,采用非衍生化液相色谱-串联质谱直接测定,电喷雾离子源负离子模式(ESI^-)下采用多反应监测模式(MRM)检测,同位素内标法定量。结果 在优化的条件下,草铵膦在5~200 μg/L范围内呈良好的线性关系,相关系数为0.9998,方法定量限(LOQ)为0.1 mg/kg。方法平均回收率为84.2%~104.9%,相对标准偏差(RSDs)低于7.6%。结论 本方法前处理简单、准确性好、灵敏度高,可用于绿茶、红茶、乌龙茶、普洱茶等茶叶中草铵膦残留量的测定。     

SPE-UPLC-MS/MS直接测定食品中草甘膦及其代谢物氨甲基膦酸

建立了一种超高液相色谱-串联质谱法直接测定食品中草甘膦及其代谢物氨甲基膦酸的方法。样品用水提取,固相萃取小柱(HLB)净化,以5 mmol/L的乙酸铵溶液和乙腈为流动相,梯度洗脱,氨基柱色谱分离,采用电喷雾离子源、负离子扫描模式和多反应监测模式测定。草甘膦和氨甲基膦酸的线性范围分别是5.00～100μg/L和10.0～200μg/L,相关系数(R2)均大于0.995。方法的检出限分别为10.0和20.0μg/kg,定量限分别为25.0和50.0μg/kg。草甘膦和氨甲基膦酸在3个加标水平(25.0, 50.0和250μg/kg; 50.0, 100和500μg/kg)下的回收率为72.1%～90.7%,相对标准偏差(RSD, n=6)为5.49%～9.01%。该方法简便、快捷、有效,前处理简单,样品无需衍生,结果稳定性高,可满足各类食品的检测需求。     

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