微流控芯片联用高效液相色谱-荧光检测器同时测定肉类食品中4种磺胺类药物残留

目的 建立一种使用微流控芯片进行肉类食品前处理,并结合高效液相色谱-荧光检测器(high performance liquid chromatography-fluorescence detector, HPLC-FLD)同时测定肉类食品中4种磺胺残留的方法。方法 样品先用乙酸乙酯提取后,在微流控芯片中用2 mol/L盐酸溶液反萃取和正己烷脱脂,收集盐酸流出液100μL,与0.5 g/mL醋酸钠溶液按照1:1(V:V)混合,加入0.2 g/L荧光胺50μL进行衍生化反应,采用岛津ODS-3色谱柱进行分离,流动相为乙腈-2%乙酸水溶液。结果 4种磺胺完全分离且在0.01～1.00mg/L呈良好的线性关系,在50、100、200μg/kg3个添加水平下,平均回收率为72.1%～91.6%,相对标准偏差为4.7%～13.6%,方法检出限为1～5μg/kg。结论 该方法具有快速、方便、经济、除脂效果好、环保等优点,适合肉类食品中4种磺胺类药物残留分析,并且提供了一个新的样品前处理思路。     

微流控芯片液液萃取结合超高效液相色谱-串联质谱法检测玉米油中黄曲霉毒素B1

目的 建立基于双Y型层流和三相层流微流控芯片的液液萃取技术,结合超高效液相色谱-串联质谱法检测玉米油中黄曲霉毒素B1的方法。方法 设计了双通道和三通道入口的的两种芯片,对芯片通道表面经过前处理,用注射泵引入含有黄曲霉毒素B1的样品溶液及萃取剂甲醇溶液于芯片中进行液液萃取,将所得的萃取液进行超高效液相色谱-串联质谱检测。对样品溶液与萃取剂的流速、芯片萃取通道的宽度等因素进行考察。结果 经纯水处理风干后的芯片,样品溶液流速为200 μL/h、甲醇流速为300μL/h,萃取通道宽度为 200μm的三相层流微流控芯片的萃取效果更好。在最优流速下平行实验6次,RSD为5.6%,芯片对黄曲霉毒素B1的萃取率为96.8%。结论 三相层流微流控芯片比双Y型层流微流控芯片对黄曲霉毒素B1的萃取率更高、萃取时间更短,并为检测其他食品污染物提供参考。     

微流控芯片电泳在食品安全分析检测中的应用研究

正微流控芯片技术是一种微量分析技术。文章介绍了微流控芯片技术的制备材料、分类,综述了该技术在食品安全检测方面的研究进展。食品安全分析检测是控制食品安全的重要手段,传统的食品安全检测技术往往依靠昂贵的仪器,专业的操作人员,且试剂和样品用量大,难以满足食品检测的微量化、集成化、便携化的检测需要。微流控芯片制备材料微流控芯片是指在一块几平方厘米的芯片上构建化学或生物实验室。它把化学和生物学等领域涉及的样品     

基于光度法快速检测余氯的微流控系统

基于微流控技术和分光光度法的原理,研制1种用于余氯快速检测的微流控芯片。设计制作的一次性微流控芯片内部预存储二乙基对苯二胺试剂,在搭建的实验平台上可以完成自动进样、反应和显色的过程。余氯的快速检测在2 min内即可完成。余氯检测的线性范围为(0.02～6)mg/L,加标回收率为92.1%～107.0%,可以满足余氯快速检测的需要。采用余氯快速检测的微流控芯片系统,有利于实现余氯检测流程的全自动化和检测设备的微型化,特别适合非专业人员进行余氯的快检。     

用于水产品中甲醛、双氧水和二氧化硫同时快速检测的微流控芯片系统研制

基于微流控技术与分光光度法,研制了一套用于水产品中甲醛、双氧水和SO_2快速检测的微流控芯片系统。该系统在一次性扇形微流控芯片上集成了进样、显色反应及检测单元,每张芯片可同时检测甲醛、双氧水和SO_2三种指标。结果显示,微流控芯片系统能够在5 min内实现对水产品中甲醛、双氧水、SO_2三种指标的准确检测,检出限分别可达到0.3、0.4、0.2 mg/L,回收率在92.38%～107.98%,相对标准偏差均低于4%。微流控芯片系统能够实现对水产品中甲醛、双氧水和SO_2进行现场、快速、全自动、高通量检测,适合基层非专业人员开展筛选需求,体现了微流控芯片在食品快速检测应用中的巨大潜力。     

自动微流控膜芯片法检测副溶血性弧菌

目的建立自动微流控膜芯片检测法副溶血性弧菌的方法。方法利用自动微流控膜芯片对副溶血性弧菌进行检测,并采用行业标准SN/T 2424-2010实时荧光PCR方法进行比对验证。结果该技术具备副溶血性弧菌的检测能力,验证实际样品的检测结果与行业标准荧光PCR法一致。结论该方法快速、准确、直观,适合测定副溶血性弧菌。     

差分脉冲伏安法检测茶叶籽油茶多酚含量

采用电化学差分脉冲伏安法建立测定茶多酚含量新方法。选择没食子酸为茶多酚标准品,研究没食子酸电化学行为;实验发现,没食子酸分子上羟基在特定电位下易被氧化,产生响应电流,且没食子酸浓度与响应电流值呈良好线性关系,绘制标准曲线,其线性范围为0.1~1.3μg/mL,线性相关系数为0.9908,且检测上线可根据测定需要继续扩大,检出限为0.04μg/mL(S/N=3)。该法可用于茶叶籽油茶多酚含量测定。     

普通PCR法、荧光定量PCR法及微流控芯片法检测大豆产品中外源基因灵敏度的比较

目的:为提高食品中转基因成分检测的灵敏度,将微流控芯片仪应用到转基因检测中.方法:将微流控芯片法与普通PCR法、荧光定量PCR法进行灵敏度比较;检测高温、高压处理过的转基因大豆粉.结果:荧光定量PCR法的灵敏度明显高于普通PCR法,但在较极端高温、高压处理(高压灭菌121℃/30min)及转基因成分含量较低(1%)的情况下,采用荧光定量PCR法未能检测到外源基因,而微流控芯片法能检测到相应的峰值,前提是在未添加内标(Marker)的情况下.若添加内标,在内标峰和目的峰区分开的条件下,有损检测灵敏度.结论:微流控芯片在转基因检测中具有高效率、高灵敏度的特点,但该方法有待完善.     

用于农药残留现场快速检测的微流控芯片研制

研制一种用于农药残留现场快速检测的微流控芯片。设计制作的一次性高聚物微流控芯片集成进样、酶抑制反应、显色反应及检测单元,结合自制的手持式光度分析检测装置,可以实现对有机磷、氨基甲酸酯类农药的现场、低成本、快速、准确的检测。结果表明：通过在芯片内部固定存储生化试剂,只需一次进样,7 min内即可实现对克百威和乐果的快速检测,最低检出限分别为0.02、0.6 mg/L,对克百威加标回收率为95.0%～103.3%,制作的芯片在1 个月内的稳定性较好。使用微流控农药残留快速检测芯片系统,有望实现全自动检测流程,特别适合于基层非专业人员开展现场、快速、高通量的农药残留筛查。     

基于改进G-四链体DNA酶的电化学适配体传感器构建及卡那霉素高灵敏检测

将阳离子多肽(peptide)与G-四链体DNA酶(G4 DNAzyme)共价组装得到高活性的G4 DNAzyme-peptide复合物,进一步构建新型电化学适配体传感器,研究该复合物对电化学适配体传感器响应性能的影响,并将该传感器用于牛奶中卡那霉素(KANA)的检测分析。结果表明：G4 DNAzyme-peptide可以显著放大电化学信号,明显提高传感器检测灵敏度;在捕获探针序列最优浓度(2.0μmol/L)下,电流信号强度变化与目标物浓度(0.06 pmol/L～20 nmol/L)对数值呈良好的线性关系,检测限为0.02 pmol/L,优于其他KANA检测方法;该传感器对KANA具有良好的选择性,在实际牛奶样品检测中,KANA的加标回收率为97.1%～105.5%,相对标准差为3.60%～5.74%,且检测结果与ELISA法一致,说明该传感器能够实现牛奶中KANA的高灵敏检测。     

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