盐酸克伦特罗快速检测胶体金试纸的研制

为建立快速检测猪尿等样品中盐酸克伦特罗（CL）的胶体金免疫层析方法,用柠檬酸三钠还原氯金酸制备了胶体金,将其标记抗CL单克隆抗体,制备了金标抗体;以CL-人血清白蛋白（HSA）为包被抗原、羊抗鼠IgG为质控线二抗,制成胶体金试纸。优化了胶体金颗粒粒径、标记抗体用量和pH值等各项参数,最终确定胶体金粒径为15 nm、每毫升胶体金溶液中添加20 ?g抗体、胶体金溶液pH值为7.4、金标抗体稀释液为添加0.1 %牛血清白蛋白（BSA）的0.05 mol/L磷酸盐缓冲液（pH 7.4）、金标抗体喷涂量为50 ?L/cm2、CL-HSA和羊抗鼠IgG的包被浓度分别0.5 mg/mL和2 mg/mL。研制的CL胶体金试纸检测限为3 ng/mL,与莱克多巴胺、沙丁胺醇等六种?-兴奋剂类药物无交叉反应。对42份猪尿样品的检测结果与市售酶联免疫（ELISA）试剂盒的符合率为100 %。试纸无需仪器辅助,操作简便,可在5 min内完成,适用于对CL残留进行现场检测。     

四氢大麻酚酸检测试纸条的研制

目的 利用胶体金免疫层析技术对因药物滥用致使尿液中产生的四氢大麻酚酸检测试纸条进行研制。方法 采用柠檬酸三钠法还原氯金酸制备胶体金。结果 确立了制备四氢大麻酚酸检测试纸条的最佳条件: 标记10 ?g/mL的抗四氢大麻酚酸单克隆抗体, 将金标抗体按喷量2.0 ?L/cm喷涂在已处理的聚酯膜上, 最后将四氢大麻酚酸-牛血清白蛋白结合物和羊抗鼠按0.5 mg/mL、1.0 mg/mL包被在硝酸纤维素膜(NC膜)上, 经过37 ℃烘箱干燥16 h, 组装制备成四氢大麻酚酸检测试纸条。结论 这种方法能在3~5 min内快速检测出尿液中残留的最小浓度为50 ng/mL的四氢大麻酚酸。     

四环素胶体金免疫检测技术的研究

为研制四环素(tetracycline,TC)胶体金免疫层析试纸条,对胶体金的制备及与四环素多克隆抗体的标记进行研究。采用柠檬酸钠还原法制备胶体金,向加热沸腾的100 mL0.01%氯金酸中加入1.8 mL1%柠檬酸钠,加热15 min后冷却定容;已制备好的胶体金溶液标记四环素抗体,将装有1 mL胶体金的离心管中加入一定量K_2CO_3调节p H值,加入一定量抗体蛋白后4℃条件下反应30 min,加入100μLNa Cl后4℃条件下保存备用,标记成功后优化条件。结果表明,胶体金颜色为紫红色、清亮透明、无沉淀及漂浮物,可见光光谱峰宽较小,证明胶体金大小分布均匀,制备成功;硝酸纤维素膜(NC膜)上有明显红色斑点,可见光光谱中最大吸收峰出现偏移,证明金标抗体标记成功;胶体金标记四环素抗体的最佳p H值为7.5,最佳标记蛋白量为稀释抗体6 000倍。胶体金的制备及与四环素多克隆抗体标记的成功,为装配四环素胶体金试纸条奠定了基础,为四环素在食品样品中快速检测方法的建立提供理论参考。     

基于免疫磁珠的胶体金免疫层析法同时检测猪肉中3-甲基-喹噁啉-2-羧酸和喹噁啉-2-羧酸

该研究建立一种基于免疫磁珠分离、净化和富集的快速、灵敏的胶体金免疫层析同时检测猪肉中的3-甲基-喹噁啉-2-羧酸(3-methylquinoxaline-2-carboxylic acid,MQCA)和喹噁啉-2-羧酸(quinoxaline-2-carboxylic acid,QCA)残留的方法。利用免疫磁珠快速提取猪肉中的MQCA和QCA,磁场快速分离,加热洗脱并富集,然后用胶体金免疫层析法检测,可在5 min内完成,MQCA定性和定量检测限均为0. 1μg/kg(QCA定性和定量检测限均为0. 25μg/kg)。结果表明,经过优化后试纸条最佳工艺为抗体标记浓度2. 5 mg/mL,抗原(T线)划膜浓度1. 2mg/mL,羊抗鼠二抗(C线)划膜浓度1. 0 mg/mL,制备免疫磁珠时亲和素磁珠与抗体最佳偶联量为40μg/mg,MQCA和QCA样本添加浓度分别为0. 1、0. 5、2和0. 25、1. 25、5μg/kg,回收率为89. 9%～115. 2%,变异系数为6. 8%～11. 5%。用基于免疫磁珠的胶体金免疫层析法和液相色谱-质谱/质谱技术(liquid chromatography-tandem mass spectrometry,LC-MS/MS)同时对20个市售猪肉样本检测,一致性较好,证明胶体金免疫检测方法可以用于实际猪肉样本中MQCA和QCA的快速定性和定量检测。     

呋喃它酮代谢物5-甲基吗啉-3-氨基-2-恶唑烷酮单克隆抗体的制备、鉴定与胶体金免疫层析试纸条的研制

目的:制备5-甲基吗啉-3-氨基-2-恶唑烷酮(AMOZ)单克隆抗体,并建立AMOZ胶体金试纸条检测方法.方法:AMOZ与对醛基苯甲酸反应生成半抗原CP-AMOZ,将CP-AMOZ与BSA、OVA偶联制备完全抗原.免疫小鼠后制备腹水型抗体,ELISA检测抗体效价与其对CP-AMOZ半抑制浓度(IC50)和最低检测限(LOD),并检测抗体的特异性.胶体金与单抗偶联,同时在NC膜上包被完全抗原、兔抗鼠多抗分别作为检测线和质控线,制备免疫层析试纸条,测定试纸条的灵敏度与特异性.结果:成功制备CP-AMOZ-BSA、CP-AMOZ-OVA完全抗原及抗CP-AMOZ的单抗,抗体效价为1∶1.6×105,对CP-AMOZ IC50为0.86μg/L,LOD 0.07 μg/L,与其他硝基呋喃类药物代谢物及其衍生物均无交叉反应.制备的胶体金试纸条灵敏度5 μg/L.结论:成功合成了CP-AMOZ的完全抗原,免疫小鼠后制备了特异性强的单抗,并以此为基础研制出敏感、特异的胶体金快速检测试纸条.     

伏马菌素B_1胶体金免疫层析快速检测试纸条的研制

目的:为制备一种快速检测玉米中伏马菌素B_1(FB_1)胶体金免疫层析试纸条。方法:采用碳化二亚胺法合成检测抗原FB_1-BSA,柠檬酸三钠还原法制备胶体金溶液,辛酸-饱和硫酸铵法对抗FB_1单克隆抗体腹水进行纯化,将金标抗体喷于金标垫,检测抗原FB_1-BSA(T线)和羊抗鼠二抗(C线)喷涂于硝酸纤维素膜(NC膜)。结果:得到的单克隆抗体效价为1.28×105。该试纸条的NC膜喷涂的检测抗原浓度为200μg/m L,羊抗鼠二抗浓度为1.0 mg/mL,喷涂量分别为0.74μL/cm,试纸条灵敏度为20 ng/mL,检测时间只需5 min,试纸条于4℃至少可保存12个月。结论:采用制备的试纸条对玉米实际样品进行检测,检测结果与高效液相和酶联免疫吸附法检测结果相一致,说明该试纸条适合现场快速检测伏马菌素B_1。     

高灵敏黄曲霉毒素B1免疫层析定量检测法的建立

以胶体金为标记物,借助于胶体金读取仪,建立了高灵敏的定量检测黄曲霉毒素B_1的胶体金免疫层析方法。试纸条制备时,当标记溶液pH为6.0,检测线全抗原的使用浓度为1.5mg/mL,金标抗体浓度为4μg/mL、用量为1.2μL时,所建立方法的灵敏度为5.7ng/L。通过加速保存试验,结果显示该试纸条的保存期大于1年。该试纸条应用于实际谷物及酱油加标样本检测,证明该方法可满足食品快速检测的需要。     

雌二醇单克隆抗体制备及胶体金侧流层析免疫分析方法的建立

目的 建立一种牛奶中雌二醇(17β-estradiol, E2)胶体金(colloidal gold, CG)试纸条快速检测方法。方法 从E2的3号位羟基和17号位羟基引入活性基团制备半抗原H1和H2, 偶联载体蛋白制备完全抗原, 经过动物免疫和细胞融合筛选, 制备单克隆抗体, 采用间接竞争酶联免疫吸附实验(indirect competitive enzyme-linked immunosorbent assay, icELISA)对单克隆抗体性能进行评估, 筛选出灵敏度最高的单克隆抗体, 最后采用静电吸附法将胶体金标记抗体为探针, 构建牛奶中E2的胶体金试纸条检测方法。结果 制备了H1-7B7、H1-9C7、H2-4A10、H2-2E2 4种单克隆抗体, 经过评估, 选取H1-9C7和H2-OVA作为最优抗体及抗原, 建立的胶体金试纸条消线(cut-off)值为6.00 ng/mL, 半数抑制浓度(half maximal inhibitory concentration, IC50)为1.54 ng/mL, 与苯甲酸雌二醇和雌三醇的交叉反应率分别为101.31%和2.43%。结论 本研究建立的试纸条具有操作简单、灵敏度高等特点, 能够基本满足牛奶中E2快速检测要求。     

胶体金免疫层析法快速检测烟叶中三唑酮残留量

[目的] 应用胶体金免疫层析技术建立一种快速检测烟叶中三唑酮残留量的方法。 [方法] 采用柠檬酸三钠还原法制备胶体金颗粒,并将其与抗三唑酮抗体标记制备得金标抗体。三唑酮-OVA偶联物和残留量羊抗鼠IgG抗体分别结合于醋酸纤维膜上,依次将样品垫、醋酸纤维膜和吸水纸组装,切割成胶体金试纸条。 [结果] 测试结果表明,三唑酮胶体金试纸条检测烟叶中三唑酮、三唑醇残留量的灵敏度为1mg/kg,检测时间为5~10 min,特异性高,重复性好,与气相色谱-串联质谱检测法符合率为98%。      

邻苯二甲酸二甲酯免疫层析快速检测试纸的研制

邻苯二甲酸酯类塑化剂是一类具有生殖毒性的环境激素类物质,通过违规添加或迁移而造成食品污染问题颇为严峻,开发适合现场的塑化剂快速监测方法非常重要。本研究以邻苯二甲酸二甲酯(DMP)为对象,建立了DMP的胶体金标记免疫层析检测试纸方法。采用柠檬酸三钠还原氯金酸制备了胶体金,将其标记DMP多克隆抗体,制备了金标抗体;采用棋盘法和单因素试验确定最佳包被浓度和二抗浓度分别为3000μg/mL和1600μg/mL,抗体浓度为稀释1.4倍,基于此建立了DMP免疫层析快速检测方法,其检测限为0.4μg/mL,5 min内肉眼可观察到检测结果,与其它结构功能类似物无明显交叉反应,特异性良好,白酒样品添加检测结果与GC-MS法相符。本法快速简单,稳定可靠,适用于实际样品中DMP的现场快速检测。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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