液相色谱串联四极杆质谱法测定猪浓缩饲料中25-羟基维生素D3含量

目的建立液相色谱-串联四极杆质谱法(liquidchromatography-tandemmassspectrometry,LC-MS/MS)测定猪浓缩饲料中25-羟基维生素D_3的分析方法。方法取适量猪浓缩饲料样品于离心管中,加水后置于振荡器上振荡破除环糊精包囊,再加入叔丁基甲醚振荡对目标物进行提取,在9000r/min条件下离心5min,氮气吹干后用2.00mL流动相溶解,过滤膜后上机测定。实验使用反相色谱柱进行分离,流动相为甲醇(0.1%甲酸)和0.1%甲酸,采用梯度程序洗脱,三重四极杆质谱进行定量定性分析,采用内标法进行计算。结果该方法的检测限为5μg/kg,定量限为10μg/kg,在2～500μg/L范围内线性良好(r≥0.999),加标回收率在77.85%～90.22%之间,相对标准偏差(relativestandarddeviation,RSD)≤8.8%。结论本方法具有良好的准确度与精密度,具有较好的实用性和专属性。     

液相色谱-质谱联用技术测定食品中罂粟碱残留

建立食品中罂粟碱残留的高效液相色谱-串联四极杆质谱联用测定方法.该方法用50%乙腈水溶液(含0.1%甲酸)提取样品,以ZORBAX Aq-C18柱(2.1×150mm,5μm)分离,流动相为乙腈和0.1%甲酸水溶液(梯度洗脱),电喷雾正离子MRM模式检测.该方法的检出限0.01 ng/mL,方法定量下限0.1μg/kg,线性范围0.01ng/mL～20.0ng/mL,加标回收率93.9%～101.2%,相对标准偏差为2.44%.     

高效液相色谱-串联四极杆质谱联用测定饼干中丙烯酰胺残留量

建立饼干中丙烯酰胺残留的高效液相色谱-串联四极杆质谱联用测定方法.该方法经纯水提取样品,以ZORBAX SB-Aq柱(4.6×150mm,5μm)分离,流动相为0.1%甲酸水溶液和乙腈(体积比为97:3),电喷雾正离子MRM模式检测.该方法的检出限0.3μg/L,方法定量下限3.0μg/kg,线性范围0.3μg/L～100.0μg/L,加标回收率91.5%～99.5%,相对标准偏差为4.44%.     

液质联用技术测定茶叶中多菌灵残留

建立茶叶中多菌灵残留的高效液相色谱-串联四极杆质谱联用测定方法。该方法中样品经0.2 mol/L盐酸甲醇溶液(1∶1,υ/υ)超声提取,MCX固相萃取柱净化,以ZORBAX Eclipse XDB-C18色谱柱(3.0 mm×50 mm,1.8μm)分离,流动相为0.1%甲酸水和乙腈(梯度洗脱),电喷雾正离子MRM模式检测。该方法的检出限为1.0μg/kg,线性范围0.5μg/L～3 000μg/L,加标回收率为85.0%～96.0%,相对标准偏差为3.71%。     

液相色谱-质谱联用技术测定豆制品中碱性嫩黄残留

本文建立了豆制品中碱性嫩黄残留的高效液相色谱-串联四极杆质谱联用测定方法。该方法用50%乙腈水溶液（含0.1%甲酸）提取样品,以MGⅢ-C18柱（2.1×150mm,5μm）分离,流动相为乙腈和0.1%甲酸水溶液（35∶65,V/V）,电喷雾正离子MRM模式检测。该方法的检出限0.5μg/kg,线性范围0.04～20.0 ng/mL,加标回收率86.2%～102.7%,相对标准偏差为5.52%。     

液相色谱-质谱联用技术测定蜂蜜中的11种磺胺类残留

建立了蜂蜜中11种磺胺类药物残留的高效液相色谱-串联四极杆质谱联用测定方法.该方法经乙腈提取样品,以ZORBAX Aq-C18柱(2.1x150mm,5μm)分离,流动相为乙腈和0.1%甲酸水溶液(梯度洗脱),电喷雾正离子MRM模式检测.该方法的检出限2.0ng/mL,方法定量下限2.0μg/kg,线性范围2.0ng/mL～100.0ng/mL,加标回收率88.6%～98.7%.相对标准偏差为2.84%～5.81%.     

基于UPLC-MS-MS技术快速测定花生中4种黄曲霉毒素

建立了花生中4种黄曲霉毒素的超高液相色谱-三重四极杆串联质谱(UPLC-MS-MS)检测的方法。样品经80%乙腈-水溶液振荡超声提取后,采用多功能净化柱净化。待测物经Kinetex SB-C18色谱柱分离,甲醇-0.1%甲酸溶液为流动相,梯度洗脱,三重四级杆串联质谱多反应离子监测(MRM)方式检测,外标法定量。结果表明:4种黄曲霉毒素在各自的线性响应范围内线性关系良好,相关系数均大于0.999,方法的检出限为0.014~0.025μg/kg,空白样品中加标回收率为72.25%~89.46%,RSD在4.01%~9.56%之间。该方法前处理简单快速、净化效果好、检出限低,适合花生中多种黄曲霉毒素的同时快速测定。     

分散固相萃取结合液相色谱串联质谱法检测牛可食性组织中吡喹酮残留量

目的建立分散固相萃取结合液相色谱串联质谱法检测牛肉、牛脂肪、牛肝和牛肾等可食性组织中的吡喹酮残留量的分析方法。方法取牛组织样品经50%(V:V)乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,正己烷脱脂,高速离心分层后,取适量乙腈层溶液经0.1%(V:V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为0.1%甲酸和乙腈溶液,采用梯度程序进行洗脱,三重四极杆质谱进行定性定量分析。结果吡喹酮在2.5～500μg/kg范围内线性关系良好(r0.995),方法的最低检出限为1μg/kg,最低定量限为2.5μg/kg,添加回收率在60%～110%,相对标准偏差(relative standard deviation, RSD)10%。结论该方法具有较好的准确度与精密度,适用于牛可食性组织中吡喹酮残留量的测定。     

HPLC-MS/MS法测定安神类代用茶中19种镇静安神类非法添加物质

建立奶粉中地塞米松的高效液相色谱-质谱/质谱测定方法。样品经甲酸乙腈溶液超声提取,经Oasis PRiME HLB固相萃取柱净化后上样。色谱条件采用Waters XBridge C18柱(2.1 mm×150 mm,5μm),流动相为0.1%甲酸水溶液-乙腈梯度洗脱,流速为0.3 mL/min,柱温40℃,采用电喷雾正离子扫描模式。结果表明:该物质检出限为1.0μg/kg,定量限为3.0μg/kg,线性范围:0～20 ng/mL。加标回收率为90.7%～98.9%。该方法操作简单高效,重现性较好,适用于奶粉中地塞米松含量的测定。     

液相色谱-质谱联用技术测定葡萄酒中的赭曲霉毒素A残留

建立葡萄酒中赭曲霉毒素A的高效液相色谱-串联四极杆质谱联用测定方法,该方法经HLB固相萃取柱净化样品,以ZORBAX Eclipse XDB-C18柱(3.0×50 mm,1.8μm)分离,流动相为0.1%甲酸水溶液和甲醇(梯度洗脱),电喷雾正离子MRM模式检测.该方法的检出限0.20 μg/L,方法定量下限0.20 μg/L,线性范围0.20 μg/L～100 μg/L,加标回收率86.6%～91.0%,相对标准偏差为1.67%.     

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