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.     

基于单克隆抗体的胶体金免疫层析法快速检测丁香酚

目的 采用免疫层析技术对丁香酚残留的胶体金免疫层析快速检测试纸条的制备开展研究。方法 用柠檬酸三钠还原法制备胶体金纳米颗粒, 标记丁香酚单克隆抗体得到胶体金-丁香酚单克隆抗体复合物。以硝化纤维素膜为固相载体, 包被丁香酚-BSA偶联物为检测带(T带), 羊抗鼠IgG为质控带(C带), 建立了丁香酚的胶体金免疫层析快速检测试纸条。结果 胶体金免疫层析试纸条具有较高的灵敏度和特异性, 检出限为2.0 mg/L。结论 本研究所开发的胶体金免疫层析试纸条可作为快速测定丁香酚的可靠、低成本的方法。     

单增李斯特菌胶体金免疫层析试纸条的研制

以单增李斯特菌(LM)内化素A蛋白(InlA)单克隆抗体为基础,研制其胶体金免疫层析检测试纸条。方法 采用DNAStar软件对LM inlA全长基因编码蛋白进行抗原表位分析,截取部分inlA基因片段构建原核表达质粒,诱导表达和纯化获得重组蛋白。以该蛋白免疫BALB/c小鼠,筛选高效分泌抗InlA单克隆抗体的杂交瘤细胞株,制备单克隆抗体;以双抗体夹心的原理研制胶体金免疫层析检测试纸条,并对其特异性、敏感性、稳定性进行评价。结果 筛选到2株高效分泌抗InlA单克隆抗体的杂交瘤细胞株,抗体属于IgG1亚类,小鼠腹水抗体效价为1∶64000;研制的试纸条可与LM发生阳性反应,而与非LM李斯特菌、链球菌、鼠伤寒沙门菌、大肠杆菌O157∶H7等食源性致病菌均不发生阳性反应;LM纯培养物敏感性为2.4×10^5cfu/ml,模拟猪肉样品敏感性为4.0×10⁶ cfu/ml;4℃保存期可达16周以上。结论 研制的胶体金免疫层析试纸条具有快速、特异、敏感等优点,可以用于样品中LM的快速检测。     

胶体金免疫层析法检测食用肉中的氨基脲

制备特异性胶体金免疫层析试纸条,检测肉类食品中氨基脲的残留。用活性酯法将氨基脲(SEM)衍生物CPSEM交联到牛血清白蛋白(BSA)上制备完全抗原CPSEM-BSA,将硫酸铵沉淀法纯化的抗CPSEM单克隆抗体标记到柠檬酸三钠还原法制备的胶体金,通过优化C/T线及金标抗体工作浓度,制备检测氨基脲的胶体金免疫层析试纸条,并对试纸条的灵敏度、特异性、准确性和稳定性进行测定。制备的试纸条检测5min后即可用肉眼观察到结果;对SEM的最低检测限达0.72ng/ml;除与呋喃西林有弱交叉反应外,与其他同类物均无交叉反应;该试纸条对猪肉中添加的SEM检测结果与酶联免疫吸附测定法(ELISA)检测结果呈现了很好的相关性;试纸条在室温下保存7周后不会失效。通过制备针对SEM的试纸条所建立的胶体金免疫层析法(ICA),快速简便、灵敏度高、特异性强、准确性和稳定性好,基本能达到商用检测要求。     

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。     

基于胶体金免疫层析技术的赤霉素快筛试纸条的研制

研制快速检测豆芽中赤霉素的快筛试纸条。采用免疫层析技术,以胶体金为标记物制备赤霉素单克隆抗体-胶体金偶联物,以竞争抑制模式制备赤霉素胶体金免疫层析试纸条。该试纸条对豆芽中赤霉素的检测限为100 μg/kg,灵敏度为98%,特异性为97%,假阴性率为2%,假阳性率为3%。该方法操作简便,具有较高的灵敏度和特异性,可广泛应用于豆芽中赤霉素残留的现场筛查和检测。     

高灵敏度磁荧光免疫层析试纸模式构建及在呕吐毒素检测中的应用

构建基于磁荧光纳米材料的免疫层析试纸模式,弥补现在免疫层析技术的不足,为更灵敏的免疫学快速检测提供技术支撑。以呕吐毒素（deoxynivalenol,DON）为靶标,采用溶剂热法制备羧基修饰的超顺磁颗粒,碳二亚胺法将磁颗粒、绿色荧光蛋白及DON单克隆抗体进行偶联,一步法制备磁荧光抗体探针,以DON人工抗原（DON-BSA）为检测线建立磁荧光免疫层析试纸。同时用胶体金标记DON单克隆抗体,以DON-BSA为检测线建立胶体金免疫层析试纸;制备的磁荧光抗体探针具有很好的磁性、荧光特性及抗体反应性,基于该探针成功制备了DON磁荧光免疫层析试纸,该试纸回归方程为y=－0.562x＋0.921,R2=0.990,IC50为5.611 ng/mL,检出限为1.089 ng/mL;制备了DON胶体金免疫层析试纸,该试纸裸眼检测灵敏度为500 ng/mL;定量检测回归方程为y=－0.543x＋1.485,R2=0.991,IC50为65.16 ng/mL,检出限为11.94 ng/mL。DON磁荧光免疫层析试纸的灵敏度是胶体金免疫层析试纸的10.96 倍。本实验建立的磁荧光免疫层析试纸模式可以同时实现样品的富集及荧光信号检测,提高检测灵敏度,并成功用于DON的检测,为磁荧光纳米颗粒广泛应用于免疫层析领域提供参考。     

呋喃西林代谢物单克隆抗体及荧光免疫层析试纸条的制备

为建立一种基于荧光免疫层析技术的呋喃西林代谢物的快速检测方法,采用活性酯法合成呋喃西林代谢物（氨基脲盐酸盐）（semicarbazide hydrochloride,SEM）人工抗原,并获得SEM的单克隆抗体,通过将量子点微球（quantumdot submicrobeads,QBs）与SEM偶联,得到QBs探针,制备荧光免疫层析试纸条。结果表明：SEM免疫荧光层析试纸条检测鱼肉组织的检测限为0.247 μg/L,不同添加质量浓度的回收率均在70%～120%之间,批内、批间变异系数均在15%以下,符合我国动物源食品中兽药残留检测方法相关指导文件的规定,且在2～8 ℃条件下可以保存6 个月以上,稳定性良好。     

双酚A快速检测胶体金试纸的研制

为建立一种快速检测双酚A(BPA)的方法,本论文建立以胶体金为基础的免疫层析法(GICA)。首先通过BPA人工抗原免疫Balb/c小鼠,然后利用正常的杂交瘤技术制备BPA的单克隆抗体,所制备的抗体经过辛酸-硫酸铵(CA-AS)沉淀法纯化后并鉴定为IgG2b亚型。胶体金是由柠檬酸三钠还原氯金酸而制得,通过紫外扫描光谱和透射电镜检测,结果表明胶体金在530 nm有单一吸收峰、粒径约为30 nm。用其标记BPA单克隆抗体,制备金标抗体。本研究所制备的胶体金免疫层析试纸条的检测限为100 ng/mL,检测时间为10 min,交叉反应表明,试纸条和BPA的结构类似物双酚酸、任基酚和辛基酚无交叉反应,有良好的再现性。该方法能够方便、快捷、有效的检测环境中的BPA,免疫层析试纸的研制为BPA进行现场快速的检测奠定了基础。     

克诺罗杆菌检测用单克隆抗体的制备及功效评价

目的:选择克诺罗杆菌标准菌株中的多株代表菌株作为抗原,采用多抗原组合免疫的方法,筛选制备抗克诺罗杆菌属(Cronobacter spp.)检测用单克隆抗体(monoclonal antibody,mAb),并对获得的抗体进行各项指标评价,为进一步建立克诺罗杆菌免疫学快速检测方法创造条件。方法:采用冻融裂解、超声破碎、全颗粒三种方法制备抗原,以克诺罗杆菌标准菌株及分离菌株20株,9株非克诺罗杆菌进行筛选。筛选获得的抗体鉴定特异性,进行Ig亚类分型,测定效价及相对亲和力常数。结果:获得6株针对克诺罗杆菌的杂交瘤细胞株,腹水效价均在1∶107以上;相对亲和常数均大于1.0×1010L/mol。采用"鸡尾酒法"将多种抗体应用到胶体金试纸条制备上,可获得检测灵敏度为105CFU/mL,特异性较好的试纸条。结论:成功制备了针对克诺罗杆菌的多株单克隆抗体,抗体特异性检测表明,所制备的6株单克隆抗体针对克诺罗杆菌不同的亚种或亚型。利用单克隆抗体建立了抗原包被间接ELISA(ACP-ELISA)和胶体金试纸条检测阪崎肠杆菌的方法。为进一步开发阪崎肠杆菌的免疫检测试纸条,建立快速的检测方法创造条件。     

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