液相色谱-串联质谱法测定鸡蛋中的喹诺酮类和四环素类抗生素

应用液相色谱-串联质谱法技术,建立鸡肉中喹诺酮类和四环素类抗生素的检测方法,并对宁夏地区市售鸡蛋进行分析。鸡蛋样品经EDTA-Mcllvaine缓冲溶液超声提取,玻璃纤维滤膜过滤,HLB固相萃取柱净化,乙腈-0.1%甲酸水溶液为流动相,用Waters Atlantis T₃色谱柱分离,以电喷雾正离子模式进行质谱测定。三个加标水平下喹诺酮类抗生素回收率为80.0%~114.0%,相对标准偏差小于12.0%,检出限(S/N=3)为0.2 μg/kg,定量限(S/N=10)为0.8 μg/kg;四环素类抗生素的平均回收率为84.5%~110.0%,相对标准偏差小于12.0%,检出限(S/N=3)为0.2 μg/kg,定量限(S/N=10)为0.8 μg/kg。该方法操作快速简单、重现性好,可用于鸡蛋中喹诺酮类和四环素类抗生素的检测。     

超高效液相色谱-串联质谱法同时测定食品中的氯酸盐和高氯酸盐残留量

目的 建立了超高效液相色谱-串联质谱法测定食品中氯酸盐和高氯酸盐残留量的方法。方法 食品样品经纯水溶解,乙腈提取,固相萃取柱净化,超高效液相色谱-串联质谱测定。采用多反应监测模式,电喷雾电离源负离子模式,内标法定量。结果 氯酸盐在0~200 ng/mL、高氯酸盐在0~100 ng/mL范围内线性关系良好,相关系数(r)均大于0.99,检出限(S/N=3)为氯酸盐6.0μg/kg和高氯酸盐1.0 μg/kg,定量限(S/N≥10)为氯酸盐18.0μg/kg和高氯酸盐3.0 μg/kg。以不含氯酸盐和高氯酸盐的样品作为空白样品进行添加回收试验,氯酸盐的回收率为83.7%~106.9%,相对标准偏差(RSD)为2.9%~6.2%,高氯酸盐的回收率为87.8%~112.8%,相对标准偏差(RSD)为2.9%~7.5%。结论 该方法不但可以有效排除复杂基体的干扰,而且简单、灵敏、稳定。     

超高效液相色谱串联质谱法测定全蛋粉中的双酚A和双酚S

建立超高效液相色谱-串联质谱测定全蛋粉中双酚A和双酚S的检测方法。全蛋粉经水复溶后经乙腈提取,提取液使用分散系固相萃取-基质增强脂质去除产品进行除脂,使用Oasis PRiME HLB小柱进一步净化,使用超高效液相串联质谱测定,负离子多反应监测(MRM)模式测定,内标法定量。结果显示:双酚A在1~50 μg/kg范围内呈线性,相关系数为0.9991,加标回收率为98.8%~105.0%,日内和日间相对标准偏差分别为3.84%~8.58%和5.65%~8.74%,检出限为0.3 μg/kg,定量限为1.0 μg/kg;双酚S在0.4~20 μg/kg范围内呈线性,相关系数为0.9995,加标回收率为98.5%~102.5%,日内和日间相对标准偏差分别为3.01%~7.86%和3.18%~7.03%,检出限为0.1 μg/kg,定量限为0.3 μg/kg。实际样品测定结果分别为:双酚A 2.4~3.8 μg/kg;双酚S 0.48~0.82 μg/kg。本方法前处理简单、高灵敏度适用于全蛋粉中双酚A和双酚S的日常测定。     

液相色谱-三重四极杆质谱法测定花茶中5种吡咯里西啶类生物碱

目的 建立液相色谱-三重四极杆质谱法(liquid chromatography-tandem mass spectrometry, LC-MS/MS) 同时测定花茶中5种吡咯里西啶类生物碱含量的分析方法。方法 将花茶样品均质粉碎后, 经0.1%甲酸水溶液浸泡, 涡旋, 超声提取, 高速离心后取上清液过固相萃取柱, 洗脱液氮吹吹干后用流动相复溶, 经ZORBAX Eclipse PLUS C18色谱柱(2.1 mm×100 mm, 1.8 μm)分离, 以0.1%甲酸溶液和乙腈为流动相进行梯度洗脱, 流速为0.30 mL/min, 柱温为30 ℃, 多反应监测模式测定, 外标法定量。结果 该方法线性关系良好, 相关系数为0.997~0.998; 方法的检出限(S/N=3)为3~5 μg/kg、定量限(S/N=10)为10~15 μg/kg; 在15、30、150 μg/kg添加水平下的平均回收率为89.69%~102.12%, 相对标准偏差为0.3%~5.4%。结论 该方法样品前处理简单快速、萃取效果好、灵敏度和选择性高, 适用于常规检测。     

QuEChERS结合液相色谱-串联质谱法测定食用菌中13种农药残留

目的:建立并应用QuEChERS结合液相色谱-串联质谱法测定食用菌中13种农药残留。方法:样品5.0 g用乙腈-水(4:1)15 mL超声提取,经N-丙基乙二胺(PSA)30.0 mg和无水硫酸镁15.0 mg分散固相萃取吸附剂净化。使用HSS T3色谱柱,0.1%甲酸和乙腈为流动相梯度洗脱。质谱采用电喷雾正离子源和多反应监测模式。结果:13种农药的质量浓度在0.5~200 μg/L范围内与峰面积呈良好的线性关系,检出限(S/N=3)0.03~0.3 μg/kg。加标回收率84.3%~102%,相对标准偏差(n=6)2.8%~6.3%。结论:该方法可用于食用菌中13种农药残留的检测。     

液相色谱-串联质谱快速检测禽类组织中 黄霉素A残留量

目的 建立检测禽类组织(肌肉、脂肪、肝脏、肾脏)中黄霉素A残留的超快速液相色谱-四极杆/线性离子阱质谱方法。方法 混合均匀的试样经10%氨化甲醇提取, 乙腈沉降蛋白净化后, 以0.3%甲酸-5%乙腈-水溶液和0.3%甲酸?5%水-乙腈为流动相, 使用Agilent Poroshell 120 SB-C18(100 mm×2.1 mm, 2.7 μm)色谱柱超快速液相色谱分离, 优化多反应检测(selected multiple reaction monitorin g, sMRM)模式检测, 外标法定量。结果 黄霉素A在20~200 μg/L线性范围内线性关系良好(r≥0.995); 黄霉素A定量限(limit of quantity, LOQ, S/N≥10)为10 μg/kg; 3个添加水平(10、20 和100 μg/kg)下的回收率为66.5%~89.4%; 相对标准偏差(relative standard deviation, RSD)为4.7%~10.2%。结论 该方法快速、准确、灵敏, 可有效用于禽类组织中黄霉素A残留的测定。     

QuEChERS-超高效液相色谱-串联质谱法测定水果中高氯酸盐

目的 建立一种测定水果中高氯酸盐的超高效液相色谱-串联质谱的分析方法。方法 水果经乙腈-水(1:1, V:V)提取, C18和GCB净化后, Waters Torus DEA色谱柱(2.1×100 mm, 1.7 μm)色谱分离, 0.9%(v/v)甲酸乙腈- 50mmol/L甲酸铵(pH 2.9)溶液进行梯度洗脱, 电喷雾负离子模式下, 多反应监测(MRM)方式进行测定, 内标法定量。结果 实验表明, 高氯酸盐在0.5~20 μg/L浓度范围内呈良好的线性关系, 相关系数r=0.9987, 方法检出限为0.8 μg/kg, 定量限为2.5 μg/kg。在浓度分别为10、20、100 μg/kg加标水平下, 高氯酸盐的回收率范围为87.7%~102%, 相对标准偏差小于6.1%。结论 该方法简单快捷、准确可靠, 适用于水果中高氯酸盐的测定。     

动物肌肉、内脏和牛奶中咪唑脲苯残留量的高效液相色谱测定及液相色谱-串联质谱确证

目的建立固相萃取净化-高效液相色谱和液相色谱-串联质谱测定动物组织和牛奶中咪唑脲苯残留量的分析方法。方法残留的咪唑脲苯采用1%三氟乙酸-乙腈(1:4,v/v)提取,Oasis WCX固相萃取柱净化,高效液相色谱外标法定量,并经液相色谱-串联质谱确证。结果咪唑脲苯检出限为10μg/kg(S/N≥3),定量限为25μg/kg(S/N≥10);在LOQ、MRL和2MRL三个添加水平下重复分析6次,回收率为72.7%~101%,相对标准偏差为1.2%~6.9%。结论该方法稳定、可靠,适用于动物组织和牛奶中咪唑脲苯的测定。     

SPE-GC/MS外标法测定水产品中4种丁香酚类麻醉剂

建立了固相萃取/气相色谱-质谱法(GC-MS)测定水产品中4种丁香酚类(丁香酚、异丁香酚、甲基丁香酚和甲基异丁香酚)麻醉剂的分析方法。样品采用正己烷-丙酮混合液(3:1,v/v)提取,乙二胺-N-丙基硅烷(PSA)净化,浓缩后再经硅胶固相萃取柱净化,采用GC-MS测定,外标法定量。结果表明:4种丁香酚类麻醉剂在5.0~200 ng/mL范围内均呈现良好线性关系,相关系数均大于0.998,方法检出限(S/N=3)均为3.0 μg/kg,方法定量限(S/N=10)均为10.0 μg/kg。空白水产品样品在0.01、0.05、0.20 mg/kg等3个加标水平时,4种目标物的平均加标回收率为85.7%~102.5%,相对标准偏差(RSD)为3.3%~9.8%。此方法净化效果较好,灵敏度高,适合水产品中4种丁香酚类麻醉剂的定性和定量分析。     

固相萃取-高效液相色谱-串联质谱法同时测定鸡蛋中42种农药残留

目的 建立固相萃取-高效液相色谱-串联质谱法同时测定鸡蛋中42种农药残留的检测方法。方法 样品经加水分散后,用乙腈提取,PRiME HLB固相萃取柱进行净化处理,采用Shim-pack XR-ODSⅡ色谱柱(75 mm×2.0 mm, 2.2 μm)分离,5 mmol乙酸铵水溶液(A)-甲醇溶液(B)为流动相,进行梯度洗脱;质谱法选择电喷雾离子源ESI,正负离子分段扫描,多反应监测(MRM)模式检测,基质匹配标准溶液外标法定量。结果 42种农药的峰面积与质量浓度在0.1~2 ng/mL范围内呈现良好的线性关系,相关系数r均大于0.994;方法检出限(LOD, S/N=3)为0.04~0.3 μg/kg,定量限(LOQ, S/N=10)为0.1~1.0 μg/kg。在1.0、2.0、5.0、10 μg/kg四个添加水平下,42种农药平均加标回收率为61.0%~118.5%,相对标准偏差为0.8%~9.9%。结论 该方法具有操作简单、分析时间短、试剂用量少、灵敏度高且重复性好等特点,适用于鸡蛋中农药残留的高通量快速检测分析。     

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