格列本脲人工抗原的合成与鉴定

目的：合成格列本脲人工抗原。方法：采用对氨基苯甲酸法制备半抗原,将半抗原分别与牛血清白蛋白(BSA)和卵清蛋白(OVA)通过碳二亚胺法偶联制备免疫原(Gli-BSA)和包被原(Gli-OVA),利用紫外扫描进行抗原的化学鉴定,通过免疫原免疫Balb/c小鼠,间接酶联免疫吸附法测定抗血清进行生物鉴定。结果：制备了Gli-BSA、Gli-OVA的人工抗原,经紫外光谱扫描,偶联比分别为4:1和17.7:1。免疫小鼠后获得抗血清的效价均达到32000以上,半抑制质量浓度为10μg/mL。结论：成功合成了格列本脲人工抗原,并获得了格列本脲抗体,为格列本脲的免疫学检测方法进一步研究提供了实验基础。     

米酵菌酸单克隆抗体的制备与鉴定

目的 建立鲜湿米粉中米酵菌酸(bongkrekicacid,BA)的免疫学快速检测方法,制备特异性识别BA的单克隆抗体并进行评价。方法 利用碳二亚胺[1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride,EDC]法将BA半抗原与牛血清白蛋白(bovineserumalbumin, BSA)和卵清蛋白(ovalbumin, OVA)载体偶联,分别合成BA免疫原(BA-BSA)和包被原(BA-OVA),用BA-BSA免疫Balb/C小鼠,取免疫效果好的小鼠脾脏与小鼠NS-1骨髓瘤细胞进行融合。采用间接竞争酶联免疫吸附法(indirect competitive enzyme-linked immunosorbent assay, icELISA)进行筛选,筛选出能分泌所需特异性抗体的杂交瘤细胞,利用有限稀释法进行亚克隆得到单株能稳定分泌所需抗体的细胞;采用体内诱生法制备腹水型单克隆抗体。利用正辛酸-饱和硫酸铵法纯化腹水型抗体,通过酶联免疫吸附法测定纯化后的抗体效价。结果 成功合成了BA免疫原BA-BSA和BA包被原BA-OV...     

环丙氨嗪完全抗原的合成及免疫原性鉴定

目的合成并鉴定环丙氨嗪(cyromazine,CA)人工抗原。方法采用碳二亚胺法(1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride,EDC)将环丙氨嗪与牛血清蛋白(bovine serum albumin,BSA)和鸡卵清蛋白(ovalbumin,OVA)分别偶联;采用紫外分光光度法(ultraviolet spectrophotometry,UV)、聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate polyacrylamide gel electrophoresis,SDS-PAGE)和动物免疫对人工抗原进行鉴定。经过4次免疫,间接ELISA测定小鼠血清抗体效价,间接竞争ELISA测定血清灵敏性。结果 UV法和SDS-PAGE法结果初步显示半抗原环丙氨嗪和载体蛋白偶联成功;小鼠血清效价均在1:6400以上,2号小鼠多抗血清半数抑制浓度IC_(50)为27.5 ng/mL。结论本研究成功合成了环丙氨嗪的人工抗原,为环丙氨嗪单克隆抗体制备奠定基础。     

膝沟藻毒素GTX 2,3完全抗原的合成与鉴定

膝沟藻毒素GTX 2,3是一类小分子物质,不具备免疫原性,欲制备其免疫血清及抗体,则必须与偶联剂及载体蛋白偶联形成完全抗原。运用乙二醛作为偶联剂,分别与牛血清白蛋白(BSA)、血蓝蛋白(KLH)合成免疫抗原GTX 2,3-glyoxal-BSA和检测抗原GTX 2,3-glyoxal-KLH,并对经超滤纯化浓缩后的偶联产物进行BCA蛋白浓度测定、全波段紫外扫描、变形SDS-PAGE凝胶电泳和抗原免疫原性的鉴定。结果表明,免疫抗原和检测抗原的蛋白质量浓度分别为8.52 mg/m L和5.72 mg/m L;经全波段紫外扫描和变形SDS-PAGE凝胶电泳鉴定,半抗原GTX 2,3-乙二醛与载体蛋白BSA、KLH偶联成功,偶联比约为1︰16和1︰20,并制备出纯度较高的免疫抗原;用制备的人工抗原GTX 2,3-glyoxal-BSA对Balb/C小鼠进行免疫,通过间接ELISA检测6免后小鼠血清效价达到1︰20 000。成功制备了具有较强免疫原性的膝沟藻毒素GTX 2,3人工抗原。     

河豚毒素人工抗原的制备及其免疫原性鉴定

目的:选择血蓝蛋白(KLH)和牛血清白蛋白(BSA)分别作为载体蛋白与河豚毒素(TTX)进行偶联制备人工抗原,并对合成结果进行鉴定。方法:通过甲醛法将TTX分别与大分子载体蛋白,即血蓝蛋白(KLH)和牛血清白蛋白(BSA)进行偶联。利用紫外扫描法、电泳法对偶联产物进行鉴定,并对6周龄Balb/c雌性小鼠免疫注射检测其免疫原性。结果:紫外扫描显示偶联抗原较载体蛋白有轻微的红移现象出现,且经过琼脂糖凝胶及SDS-PAGE 2种方法电泳检测后发现,载体蛋白较人工抗原之间迁移率均不相同;对免疫小鼠进行间接酶联免疫吸附试验(iELISA)及间接竞争酶联免疫吸附试验(icELISA)联用检测其多抗血清效价及特异性,经过共计6次免疫后的效价能达到1:40w,且能有效抑制TTX。结论:河豚毒素人工抗原制备成功且具备良好的免疫原性。     

莱克多巴胺和土霉素人工抗原的合成及鉴定

研究莱克多巴胺和土霉素免疫抗原的制备。实验中用碳二亚胺法将莱克多巴胺(ractopamine,RAC)与载体蛋白牛血清白蛋白(bovine serum albumin,BSA)偶联,制备完全抗原;采用混合酸酐法将土霉素(oxytetracycline,OTC)与载体蛋白BSA偶联,制备完全抗原,并对合成产物进行表征。紫外扫描对合成产物RAC-BSA、OTC-BSA进行鉴定结果显示偶联成功,经重氮化后利用混合酸酐法制备完全抗原的偶联比为5:1;经衍生后利用碳二亚胺法制备RAC完全抗原偶联比为7:1。利用制备的免疫原免疫兔子可以获得相应的抗体。     

甲基苯丙胺与蛋白偶联物的合成

研究合成甲基苯丙胺抗原.在甲基苯丙胺分子上引入偶联官能团,以牛血清白蛋白(BSA)为载体蛋白,用戊二醛法偶联合成了甲基苯丙胺抗原,并用红外光谱、紫外扫描、蛋白电泳以及胶体金免疫层析等方法进行检测.结果表明,每分子BSA连接甲基苯丙胺分子数为25;胶体金免疫层析检测结果显示合成抗原与抗体有特异性反应,具有活性.可在免疫检测中用作抗原的甲基苯丙胺与蛋白偶联物.     

对氯甲基苯甲酸链接的莱克多巴胺人工抗原的合成与鉴定

采用对氯甲基苯甲酸(CBA)为链接臂,用混合酸酐法将莱克多巴胺(RAC)与牛血清白蛋白(BSA)偶联制备人工抗原(RAC-CBA-BSA),通过紫外、红外、电泳鉴定抗原合成成功;再以卵清蛋白(OVA)为载体蛋白合成包被抗原(RAC-CBA-OVA),测定其与抗体的亲和力和抑制率。间接竞争ELISA结果以对CBA为链接臂合成的包被抗原对应的抗体滴度为7047.3、IC50为17.05ng/mL,结果表明,CBA可以用于RAC人工抗原的合成,使用RAC-CBA-OVA作为包被抗原可以提高ELISA检测灵敏度。     

罗丹明123人工抗原的合成及抗体的酶联免疫检测

为建立罗丹明B(rhodamine B)的免疫分析方法,采用戊二醛法,将半抗原罗丹明123与载体牛血清白蛋白(BSA)及卵清蛋白(OVA)偶联制备免疫抗原R123-B S A和包被抗原R123-OVA。经动物免疫实验证实人工抗原合成,并制备抗罗丹明123的多克隆抗体,此抗体同时能够检测食品中的罗丹明B,且最低检测限为0.001ng/mL。     

2,4-二氯苯氧乙酸人工抗原合成及鼠源多克隆抗血清的制备

采用碳化二亚胺法(EDC法)将2,4-D与牛血清白蛋白(BSA)及卵清蛋白(OVA)偶联,合成免疫原2,4-D-BSA和包被原2,4-D-OVA,采用紫外扫描(UV)和聚丙烯酰胺凝胶电泳(SDS-PAGE)法进行鉴定;用2,4-D人工免疫抗原(2,4-D-BSA)免疫BALB/c纯系小鼠,采用间接ELISA测定多抗血清效价、阻断ELISA鉴定其抑制。结果表明:BSA与2,4-D偶联后,波峰出现右移,表明偶联成功;SDS-PAGE电泳中BSA的泳动速度大于2,4-D-BSA,表明2,4-D已与BSA成功偶联;6只小鼠血清效价均达到了1:1.28×104,且1号小鼠多抗血清敏感性最好,半数抑制IC50为72.48ng/mL,表明成功获得了高效价、特异性好、亲和力较高的鼠源抗2,4-D多克隆抗体血清,为2,4-D残留免疫学检测方法的建立奠定了良好的基础。     

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