基于树状分子提高AMOZ半抗原免疫原性的研究

3-氨基-5-吗啉甲基-2-恶唑烷酮(AMOZ)是抗生素呋喃它酮的代谢产物,具有潜在致畸、致癌性。由于分子量太小,其特异性抗体制备尚未突破,无法建立直接检测的免疫分析方法。为了制备针对AMOZ的特异性抗体,本研究首次尝试采用赖氨酸树状分子(G5)替代传统载体蛋白,将AMOZ的乙醛酸衍生半抗原AMOZA直接偶联到G5分子上制备免疫原(AMOZA-G5),免疫Balb/c小鼠,收集抗血清并进行间接竞争酶联免疫分析(ci ELISA)测定。结果发现:传统免疫原AMOZA-BSA对应的抗血清无法特异性识别游离AMOZ,而AMOZA-G5对应的抗血清则可以特异性识别游离AMOZ,在ci ELISA实验中,1μg/m L AMOZ对抗体活性的抑制率为35%,说明以赖氨酸树状分子为载体可以有效提高小分子半抗原的免疫原性。本研究对于制备其他小分子半抗原的特异性抗体提供了方法借鉴。     

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.     

雷洛昔芬抗体的制备及ELISA方法的初步建立

本文主要研究了雷洛昔芬抗体的制备和酶联免疫吸附测定(enzyme-linked immuno sorbent assay,ELISA)方法的初步建立。实验中采用丁二酸酐对雷洛昔芬进行衍生,合成了雷洛昔芬半抗原。采用碳二亚胺法,将雷洛昔芬半抗原与牛血清白蛋白(BSA)和卵清蛋白(OVA)偶联合成免疫原和包被抗原,并通过紫外光谱进行鉴定,结果显示雷洛昔芬与载体蛋白偶联成功。免疫大白兔制备了雷洛昔芬抗体,抗体效价达1.28×10~5,半数抑制浓度(half inhibit concentration,IC50)15.4μg/L,与其他类似抗雌激素药物没有交叉反应,说明所制备的抗体特异性好。通过优化抗原抗体反应浓度初步建立了雷洛昔芬ELISA方法,结果显示最佳抗原浓度为300μg/L,最佳抗体工作浓度为1:1.0×10~5,标准曲线在0.4~102.4μg/L范围内线性关系好,R~2=0.9853,最低检测能力0.4μg/L。本研究为进一步开发雷洛昔芬快速检测试剂盒提供了技术参考。     

鸡肉中金刚烷胺间接竞争ELISA检测方法的建立

建立检测鸡肉中金刚烷胺的间接竞争酶联免疫吸附分析(indirect competitive enzyme linked immunosorbent assay,ic-ELISA)法。利用N-(1-金刚烷胺基)肼甲酰胺与乙醛酸合成新式金刚烷胺半抗原,采用活泼酯法将金刚烷胺半抗原分别与血蓝蛋白、牛血清白蛋白偶联合成免疫原和包被原,将所制备的人工抗原免疫BALB/c小鼠,并制备特异性识别金刚烷胺的单克隆抗体。ic-ELISA法经系统优化后,最佳包被原稀释倍数为80 000,抗体工作质量浓度为122.50μg/L,对金刚烷胺的IC50为0.69μg/L,检出限为0.21μg/L,在0.07～6.15μg/L之间线性良好,鸡肉样品中添加回收率为101.69%～108.71%,变异系数均低于15%,且实际样品检测结果与高效液相色谱-质谱联用测定结果相关性良好(R2=0.97),表明建立的ic-ELISA具有良好的准确度和可靠性。利用该特异性抗体建立的方法适用于实际鸡肉样品中金刚烷胺的快速检测。     

酶联免疫吸附法测定水产品中甲基睾酮残留

建立了测定水产品中甲基睾酮(MT)残留的间接竞争酶联免疫吸附法(ic ELISA)。采用琥珀酸酐法衍生化制备半抗原MT17,进一步偶联钥孔血蓝蛋白(KLH)制备免疫原MT17-KLH,经动物免疫成功获取特异性识别MT的多克隆抗体(与其它结构类似物交叉反应小于1%)。优化确立了ic ELISA最佳检测条件:包被原浓度100μg/L,MT多克隆抗体稀释度1/1.2×105,抗体反应时间40 min,药物稀释液为PBS,水产样品经乙腈提取,N-丙基乙二胺吸附剂(PSA)分散固相萃取(DSPE)净化后用于ic ELISA测定。本方法的抑制中浓度IC50为3.48μg/L,检测线性范围为0.77~13.06μg/L。水产样品加标回收率为81.02~103.19%,相对标准偏差为4.46%~13.14%,测定结果与液相色谱-质谱联用法具有良好的相关性(R=0.9971)。本方法可用于水产品中甲基睾酮残留的快速测定。     

西马特罗单克隆抗体制备以及酶联免疫试剂盒的研究

通过制备西马特罗半抗原,载体蛋白与之偶联合成免疫原,免疫原用于免疫动物,获得抗西马特罗单克隆抗体,制备能够检测猪尿中西马特罗残留量的酶联免疫试剂盒。结果表明,该试剂盒对猪尿中西马特罗的检测限为0.295 μg/L,半抑制浓度（IC50）值为0.870 μg/L,回收率范围为81.5%～103.5%,标准曲线线性范围为0.1～8.1 μg/L,精密度试验结果批内、批间的相对标准偏差（RSD）均＜15%,表明该检测方法准确度和精密度高。该试剂盒特异性较好,于4 ℃条件下能够保存12个月,稳定性较好,可以用于猪尿中西马特罗德快速检测。     

花生致敏蛋白Ara h 3单克隆抗体的制备及其免疫学特性鉴定

以Ara h 3为免疫原免疫小鼠。选取血清效价高的小鼠再次免疫，制备出脾细胞后与骨髓瘤细胞一起进行细胞融合，得到杂交瘤细胞株，筛选阳性株制备大量单克隆抗体。通过酶联免疫吸附试验(ELISA)对制备的单克隆抗体进行效价测定、敏感性测定和特异性测定。通过蛋白质免疫印迹试验进一步验证其特异性。结果表明：免疫性较好的4B2单克隆抗体经纯化后的效价为1∶5.12×10⁵。由敏感性测定得知4B2单克隆抗体的半抑制浓度(IC₅₀)为389 ng/mL,证明其具有较好的敏感性，交叉反应率小于0.5%,成功制备出纯度高、效价高、敏感性好、特异性强的Ara h 3鼠源单克隆抗体，为建立免疫学快速检测方法奠定了基础。     

孔雀石绿多克隆抗体的制备与筛选

设计并成功合成了三种孔雀石绿半抗原,所有半抗原均采用活化酯法分别与血匙兰蛋白(KLH)偶联制备成免疫抗原,与卵清蛋白(OVA)偶联制备成包被抗原。利用所制备的三种免疫原免疫新西兰大耳白兔都获得了高效价的抗孔雀石绿抗体,并将每一种抗体都与三种包被抗原进行组合配对,通过间接竞争酶联免疫吸附检测(ELISA)方法筛选出最佳的抗体-包被抗原组合,筛选出的抗体采用Sepharose FF-Protein A亲和层析柱纯化,采用间接ELISA法测定效价及鉴定特异性。经测定筛选出的抗体效价达到1:12000,IC50值为0.65 ng/mL,交叉反应表明该抗体有较好的特异性,与结构类似物结晶紫的交叉反应率为18.73%,与隐性孔雀石绿及隐性结晶紫的交叉反应率低于10%。本研究为建立快速检测食品中孔雀石绿残留的免疫分析方法奠定了基础。     

呋喃唑酮代谢物单克隆抗体和胶体金免疫层析试纸条的研制

本研究旨在建立一种快速检测呋喃唑酮代谢物残留的方法。试验用呋喃唑酮代谢物的衍生物（CPAOZ）与牛血清白蛋白（BSA）的偶联物免疫小鼠,利用单克隆抗体技术制备杂交瘤细胞,用间接ELISA和间接竞争ELISA法对阳性克隆进行筛选。单克隆细胞株诱生腹水后,经纯化即为单克隆抗体,用于胶体金标记,制备呋喃唑酮代谢物胶体金免疫层析试纸条。融合后得到2株稳定分泌抗体的杂交瘤细胞株,其中4G3纯化后的抗体效价达到1:100万,对CPAOZ的50%抑制质量浓度（IC50）为1.7 μg/L,亲和常数Ka=1.6×109 L/mol。该抗体制备的胶体金试纸条的检测限为4 μg/L,与其他3种硝基呋喃代谢物的衍生物CPAHD、CPSEM和CPAMOZ均不存在交叉反应,对样品的检测与高效液相色谱结果一致。本研究制备了抗呋喃唑酮代谢物特异性单克隆抗体,并研制了以单抗为基础的胶体金免疫层析试纸条,能够实现呋喃唑酮代谢物残留的快速、灵敏的检测。     

有机磷农药三唑磷单克隆抗体制备及鉴定

采用活泼酯法和混合酸酐法将三唑磷半抗原(TZPM-Hap)与牛血清蛋白(BSA)和卵血清蛋白(OVA)偶联,分别制备出一种免疫抗原(TZPM-A-BSA)和两种包被抗原(TZPM-A-OVA和TZPM-M-OVA)。通过免疫小鼠及细胞融合,并对杂交瘤细胞进行经多次筛选和亚克隆得到1株产三唑磷单克隆抗体阳性细胞株(FC3),其抗体亚类为IgM。辛酸-硫酸铵沉淀法纯化后的抗体经间接ELISA检测,该方法IC50=9.7μg/L,最低检测限(LOD)为1.0μg/L,定量检测线性范围(IC20～IC80)为2.5～100.0μg/L,与其他有机磷农药结构类似物无明显交叉反应,显示出高度的特异性。该抗体可进一步用于免疫分析试剂盒开发。     

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