QuEChERS-高效液相色谱-质谱/质谱法同时测定水产品中磺胺类和氯霉素类药物

目的 建立QuEChERS-高效液相色谱-质谱/质谱法同时测定水产品中磺胺类药物和氯霉素类药物含量的分析方法。方法 样品用乙腈提取, 经QuEChERS方法去脂净化后, 用甲醇和0.02%的甲酸水溶液作为流动相进行梯度洗脱, Waters Atlantis T3色谱柱进行色谱分离, 高效液相色谱-质谱/质谱电喷雾电离多反应监测正负离子模式测定, 内标法定量。结果 23种药物标准曲线的相关系数均大于0.99, 加标平均回收率为61.4%~116.2%。结论 本方法操作简单、方便高效, 可同时测定水产品中磺胺类和氯霉素类药物, 适合于实验室多项目的快速检测。     

超高效液相色谱-串联质谱法快速筛查水产品中氯霉素类药物残留

建立了高效液相色谱-串联质谱法快速筛查水产品中三种氯霉素类残留的定性定量分析方法。样品经正己烷除脂后用正己烷饱和的乙腈提取,氮气下浓缩至干用流动相复溶,采用电喷雾负离子模式下多反应监测(MRM)模式进行检测,基质匹配标准溶液定量分析。结果表明,在0.5-20 ng/mL的浓度范围内,三种氯霉素具有良好的线性关系,相关系数均大于0.999 8,方法检出限为0.001-0.006μg/kg。在鱼、虾、蟹三种水产品基质中的加标回收率为61.8-103.6%,相对标准偏差(RSD)为2.7-10.9%。该方法简便快速、准确可靠,适用于对大批量水产品样品中氯霉素类残留的快速筛查。     

水产品中四环素类药物残留的超高效液相色谱-串联质谱测定

建立同时测定水产品中6 种四环素类药物残留的超高效液相色谱- 串联质谱(UPLC-MS/MS)分析方法。用0.01mol/L Na2EDTA-Mcllvaine 磷酸盐缓冲溶液提取,样液过滤后正己烷除脂,经Oasis HLB 固相萃取柱净化,甲醇洗脱,氮气吹干缓冲液定容后,用反相液相色谱分离,电喷雾正离子模式离子化,用多反应监测模式(MRM)监测,三重四级杆质谱测定,外标法定量。该法对四环素类药物在5.0～50.0μg/kg 范围内呈线性关系,相关系数r 在0.9969～0.9999 之间,在5.0、10.0、25.0、50.0μg/kg 添加水平,回收率为61%～97%,相对标准偏差(RSD)为1.3%～5.7%,其检出限达2.5μg/kg,方法操作简便,稳定性好,选择性好,灵敏度高。     

超高效液相色谱-电喷雾串联质谱法同时测定生菜中四环素类抗生素及其代谢产物

目的建立超高效液相色谱-电喷雾串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)测定生菜中9种四环素类抗生素及其代谢产物的残留分析方法。方法生菜样品采用EDTA-Mcllvaine缓冲液与乙腈混合溶液提取,HLB固相萃取小柱净化,色谱分离选择ACQUITY UPLC BEH C18色谱柱,以乙腈和0.2%甲酸水溶液为流动相进行梯度洗脱,得到的分离效果较好。质谱采用电喷雾正离子电离、多反应监测模式检测。结果在0.01~0.5 mg/L范围内线性相关系数r2均大于0.99。仪器检出限为1.085~15.780μg/kg,方法的定量限为3.617~42.526μg/kg。在4个添加水平0.01、0.05、0.1和0.5 mg/kg下,除脱水四环素和差向脱水四环素(其回收率40%)外,其余四环素类抗生素及代谢产物在蔬菜中的添加回收率在为63.4%~101.3%,相对标准偏差为2.52%~12.56%。结论该方法灵敏度高,净化效果好,可以用于蔬菜中四环素类抗生素及其代谢产物的残留分析。     

多壁碳纳米管小柱-液质联用法测定鸡肉中兽药残留方法的研究

本实验建立了鸡肉中喹诺酮类、磺胺类、氯霉素类、四环素类兽药残留的液相色谱-串联质谱快速测定方法.研究了鸡肉中4类兽药残留的提取、净化前处理条件,试样用2.5％甲酸乙腈溶液提取,滤过型多壁碳纳米管小柱净化,Accucore VDX色谱柱梯度分离,三重四极杆质谱测定,基质标准曲线法定量.同时以电喷雾离子源正模式和负模式扫描...     

液相色谱-串联三重四极杆质谱测定牛奶中的氯霉素残留量

建立牛奶中氯霉素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MGⅢ-C18柱(2.1×150 mm,1.8μm)分离,流动相为水溶液和乙腈(体积比为65∶35),电喷雾负离子MRM模式检测。该方法的检出限0.07μg/L,线性范围0.05μg/L~20.0μg/L,加标回收率98.5%～110.8%,相对标准偏差为3.57%。     

超高效液相色谱-串联质谱法测定鸡肉和鸡蛋中氯霉素和甲硝唑

目的建立超高效液相色谱-串联质谱法检测鸡肉和鸡蛋中的氯霉素和甲硝唑。方法鸡肉和鸡蛋样品经乙腈沉淀蛋白,乙酸乙酯和乙腈同时提取,Oasis MCX柱净化,以乙腈-水为流动相,采用ACQUITY BEH C18(2.1 mm×100 mm,1.7μm)色谱柱分离,分别以电喷雾负离子和正离子模式进行质谱测定,内标法定量。结果分别以鸡肉和鸡蛋为加标基质,三个加标水平下氯霉素和甲硝唑的平均回收率为96.3%~110.5%,相对标准偏差小于7.0%,氯霉素和甲硝唑的检出限(S/N=3)为0.1μg/kg,定量限(S/N=10)为0.3μg/kg。结论该方法操作快速简单、重现性好,可用于鸡肉和鸡蛋中氯霉素和甲硝唑的含量测定。     

超高效液相色谱质谱联用仪测定水产品中敌百虫的含量

建立敌百虫在水产品中残留量的超高效液相色谱-电喷雾质谱(UPLC-MS/MS)测定方法。用乙酸乙酯提取样品中的敌百虫,提取液经酸性氧化铝柱净化,经超高效液相色谱分离,用串联质谱测定,正离子多反应监测(MRM)模式检测,外标法定量。在0.02～0.8ng/mL范围内,敌百虫标准工作溶液的色谱峰面积与质量浓度成良好的线性关系,相关系数r=0.9992;水产品中敌百虫的添加回收率在89.0%～93.8%,相对标准偏差为2.1%～5.4%,检出限为1.0μg/kg。方法简便、快速、准确,保留时间为1.5min。     

LC-MS/MS测定人参蜂王浆口服液中15种药物残留

建立了同时测定人参蜂王浆口服液中15种抗生素药物(6种喹诺酮类、4种四环素类、3种大环内酯类、2种林可胺类)残留的高效液相色谱-串联质谱(LC-MS/MS)检测方法。该方法采用pH8.0磷酸盐缓冲液提取样品,提取液经HLB固相萃取柱净化。以甲醇-乙腈-0.1%甲酸作为流动相,C18色谱柱对15种药物进行分离,电喷雾正离子多反应监测模式进行检测。方法检测限为0.02ng/mL~0.9ng/mL,线性范围0.08ng/mL~20ng/mL,加标回收率为71.8%~87.8%,相对标准偏差为2.2%~7.9%(n=9)。该方法准确、灵敏、简便,适用于人参蜂王浆口服液中四环素等药物残留的测定。     

水产品中氯霉素检测条件的优化

目的建立液相色谱串联质谱法测定加工水产品中的氯霉素,并对提取溶剂、净化条件、流动相进行了优化。方法样品采用乙酸乙酯提取,HLB固相萃取柱净化,C_(18)色谱柱分离,ESI源负离子模式对氯霉素进行检测。结果氯霉素在0.1~10μg/kg范围内线性关系良好,相关系数为0.999,在基质样品中添加0.1、0.2和10.0μg/kg 3个水平药物,其回收率在95.0%~103.2%之间,相对标准偏差3.72%~6.85%,方法检测限为0.1μg/kg.结论该方法可靠、稳定,可满足加工水产品中氯霉素残留检测与确证需要。     

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