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。     

重金属铅多克隆抗体的制备及鉴定

目的：合成铅离子完全抗原,并对其进行鉴定;用合成的完全抗原免疫Balb/c 小鼠制备多克隆抗体,鉴定效价和特异性。方法：用双功能螯合剂p-SCN-Bn-DTPA 将Pb2+ 与载体蛋白BSA 和OVA 偶联在一起,合成免疫抗原(Pb-DTPA-BSA)和检测抗原(Pb-DTPA-OVA),并通过SDS-PAGE、紫外扫描、电感耦合等离子体(ICP) 检测抗原中Pb2+ 含量,以及通过免疫Balb/c 小鼠,采集血清进行间接ELISA 和竞争ELISA 检测。结果：两种合成的抗原相对于各自的载体蛋白均出现了蛋白条带滞后,紫外吸收峰偏移等现象;免疫的4 号和5 号Balb/c 小鼠的抗血清效价达1:400000;与OVA 无交叉反应,ELISA 检测IC50 值为1.5ng/mL,与Fe3+ 有近5% 的交叉反应,与其他重金属离子的交叉反应均小于1%。结论：铅离子多克隆抗体制备成功。     

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。     

1-芘丁酸人工抗原的制备及鉴定

为制备及鉴定1-芘丁酸（1-pyrenebutyric acid）人工抗原。采用碳化二亚胺（EDC）法将1-芘丁酸与牛血清白蛋白（BSA）和鸡卵清白蛋白（OVA）进行偶联,合成人工免疫原PBA-BSA和人工检测抗原PBA-OVA;紫外扫描及SDS-聚丙烯凝胶电泳（SDS-PAGE）结果显示抗原制备成功;鼠源多抗血清的效价均已超过1 000,IC₅₀=14.31 ng/mL;与多环芳烃1-芘甲醇、1-芘甲醛、芘的交叉反应率小于14.40%,与菲、萘、苯并芘、BSA以及OVA交叉反应率均小于0.05%。作者成功制备出了PBA-BSA抗原,并且得到了敏感性良好的鼠源多抗血清,为后期单克隆抗体的制备及免疫学快速检测方法的建立奠定基础。     

酶联免疫吸附法快速检测畜禽产品中西马特罗药物残留

为建立高效的西马特罗(Cimaterol, CIM)检测方法,试验用以重氮化法合成的西马特罗完全抗原免疫新西兰大白兔,提取兔脾细胞总RNA,反转录合成cDNA第一链,设计兼并引物,扩增兔源抗体重链可变区(VH)和轻链可变区(VL),通过45 bp的连接肽(Linker)连接成VH-Linker-VL并大量扩增;利用噬菌体表面展示技术将单链抗体(ScFv)片段与噬菌体展示载体pCANTAB-5e连接,电转化至大肠杆菌TG1感受态细胞,得到兔源噬菌体ScFv抗体库。通过聚丙烯酰胺凝胶电泳(SDS-PAGE)判断是否偶联成功,用紫外扫描(UV)及基质辅助激光解析串联飞行时间质谱(MALDI-TOF-MS)测定人工抗原的偶联比。将富集的抗体库侵染对数期大肠杆菌进行抗体库滴度测定合成抗体库的质量进行鉴定,对抗体库进行三轮淘选,取最优的CIM-ScFv进行氨基酸序列分析。结果表明：CIM-BSA及CIM-OVA偶联比分别为8:1及10:1,CIM-BSA免疫原免疫新西兰大白兔,间接ELISA测得免疫血清校价为1:32000,免疫血清半数抑制浓度为9.77 ng/mL, 曲线的拟合度为0.997。抗西马特罗兔源噬菌体ScFv免疫库的插入率为92%,库容为1×10_¹⁰ pfu,多样性为83.3%,经过4轮淘选,获得一株与CIM有结合活性的噬菌体ScFv菌。以上结果表明西马特罗完全抗原的合成效果良好,可用于建立西马特罗检测方法,兔源噬菌体抗体库为快速获得CIM单链抗体奠定基础,为西马特罗快速检测提供新思路。     

超声/紫外强化Fenton法深度处理造纸废水研究

本研究采用超声/紫外强化Fenton法深度处理造纸废水,以COD、BOD去除率为评价指标,研究反应时间、超声功率和频率、紫外强度、H₂O₂和FeSO₄·7H₂O投加量、pH值对处理效果的影响。结果表明,超声/紫外强化Fenton法深度处理造纸废水的最佳处理条件为：反应时间90 min、超声功率160 W,超声频率50 kHz、紫外光强度12 mW/cm²、H₂O₂投加量12 mL/L、FeSO₄·7H₂O投加量500 mg/L、溶液pH值=5,最佳反应条件下造纸废水的COD_Cr和BOD₅去除率分别为74.8%和75.5%。超声/紫外强化Fenton法深度处理造纸废水具有协同效应,其处理效果优于超声+紫外+Fenton法。超声/紫外强化Fenton法深度处理后,造纸废水满足《城镇污水处理厂污染物排放标准》GB 18918—2002一级A排放标准。     

电感耦合等离子体质谱法测定芦荟、人参、五味子、龙胆草中5种重金属含量

目的：建立用电感耦合等离子体质谱(ICP-MS)法测定辽宁地区芦荟、人参、五味子、龙胆草中铜、镉、铅、砷、汞5种重金属含量的方法。方法：微波消解法处理样品,采用ICP-MS法测定,射频功率1 500 W,采用碰撞模式,碰撞气为氦气,载气为氩气,载气流速0.7 L.min_^-1,等离子体气体流速15.0 L.min_^-1,泵速0.3r.s_^-1。结果：5种重金属线性关系良好(r>0.999 0)；加样回收率为89.8%～96.9%(n=6)；检测限为0.0002～0.006mg.kg_^-1。结论：本方法准确可靠、灵敏简便,可用于芦荟、人参、五味子、龙胆草中多种重金属的质量研究,同时为测定同类中药材中此5种重金属提供参考。S     

Cd2+-PVA/PA6金属配合纳米纤维的制备及反应动力学分析

 利用静电纺丝技术得到PVA/PA6复合纳米纤维,并将其与镉离子（Cd2+）溶液反应,制备Cd2+-PVA/PA6金属配合纳米纤维。采用原子吸收光谱（AAS）测定金属离子浓度,用傅里叶红外光谱(FTIR)对PVA/PA6复合纳米纤维和Cd2+-PVA/PA6金属配合纳米纤维的相应吸收峰进行分析,用扫描电子显微镜（SEM）对其形貌进行表征。结果表明,PVA/PA6纳米纤维具有优异的金属离子配合性能和良好的形态稳定性。同时研究了金属离子吸附过程及动力学参数,得出吸附常数K_l=0.0257 L/mmol、饱和离子配合量Q_m=4.4643 mmol/g,相关系数R²=0.997,该反应过程符合兰格缪尔吸附模型。     

碱木质素碳点的制备及对Fe3+检测性能研究

以碱木质素（Alkali lignin,AL）为碳源、乙二胺（Ethanediamine,EDA）为钝化剂、双氧水（H₂O₂）为氧化剂,利用简单、绿色、高效的水热法制备碱木质素碳点（ALE-CDs）。以荧光性能为指标,通过单因素实验优选出ALE-CDs的最佳制备工艺。结果表明,ALE-CDs表面存在大量的羟基（—OH）、羧基（—COOH）和氨基（—NH₂）等官能团,在水中具有优良的分散性和稳定性,荧光量子产率及寿命分别为19.20%和6.03 ns。利用ALE-CDs为荧光探针检测不同金属离子,发现ALE-CDs对Fe³⁺表现出较好的选择性,荧光强度与Fe³⁺浓度（0~50 μmol/L）呈良好的线性关系,Fe³⁺检出限约为1.66 μmol/L。     

磺胺二甲嘧啶间接竞争化学发光酶免疫分析法的建立及应用

建立一种更加灵敏的磺胺二甲嘧啶(SM₂)免疫学检测方法。方法 本研究制备抗SM₂单克隆抗体(SM₂-mAb),用于建立SM₂间接竞争化学发光酶免疫分析法(SM₂-CLEIA),并检测主要动物食品中SM₂残留。结果 本研究制备的SM₂-mAb为IgG_2b亚类,亲和常数为0.12×10⁷ L/mol;SM₂-CLEIA曲线在0.1～1 000 μg/L之间呈现良好的线性关系,相关系数r²=0.990 4,半数抑制浓度(IC₅₀)为4.006 μg/L,检测限为0.174 μg/L,添加回收率为94.41%～104.40%,批内和批间变异系数分别为3.07%和8.22%,与磺胺脒等药物无交叉反应,与SM₂-ELISA试剂盒的阴阳性符合率为100%。结论 建立了灵敏、特异、准确、检测范围宽的SM₂-CLEIA检测方法。     

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