基于广谱性单克隆抗体免疫分析有机磷农药残留

目的制备和筛选出一种能识别一类或几类具有结构相似的有机磷杀虫剂的广谱性鼠单克隆抗体(m Ab)以对多农药残留同时进行检测。方法制备抗有机磷组特异性单克隆抗体,利用间接竞争性ELISA法对几种有机磷农药的标准品进行检测。结果对乙基毒死蜱检测灵敏度较高,最低检测限(LOD)为4 ng/m L,对甲基对硫磷的LOD为63 ng/m L;辛硫磷和三唑磷的检测敏感度低、一致性差。结论根据农药化学结构的不同,检测灵敏度有一定的差别,对乙基毒死蜱和甲基对硫磷检测效果较好。     

胶体金试纸与气相色谱法检测毒死蜱结果相符率比较

目的通过研究胶体金法与气相色谱法在检测毒死蜱中的应用,证实胶体金试纸条在检测蔬菜中毒死蜱残留的可靠性。方法对比胶体金试纸半定量法和气相色谱定量法检测毒死蜱的结果。结果胶体金试纸条检测阴性样品得出的结果与气相色谱的结果符合率为100%,添加的阳性样品符合率也达到100%。添加的界限值样品的回收率达到96%。结论与气相色谱法相比较,胶体金试纸检测毒死蜱操作简便、观察直观、快速、省时,其特异性、敏感性较高,可作为蔬菜采摘前毒死蜱农药残留自我检测的手段。并可以此为基础建立一个不同于以前的毒死蜱监管模式。     

腈菌唑单克隆抗体制备与胶体金检测方法的建立

目的 制备高灵敏度腈菌唑单克隆抗体,建立芹菜样本中腈菌唑胶体金快速检测方法。方法 对腈菌唑化学结构进行改造,合成两种半抗原,与载体蛋白偶联,免疫小鼠,制备单克隆抗体。结合胶体金技术,优化抗体标记参数等,建立胶体金的检测方法,并对检测性能进行评价。结果 由所制备的单克隆抗体开发的胶体金试纸条半数抑制浓度为2.10μg/L,线性范围为0.62～7.25μg/L,与其他三唑类杀菌剂和芹菜中常见杀虫剂的交叉反应率均小于5%;可定性检测芹菜样本中腈菌唑是否超过GB2763—2021《食品安全国家标准食品中农药最大残留限量》限量,检出限为50μg/kg;通过实际阳性样本测试与气相色谱-串联质谱法比较,符合性较好,结果可靠。结论 基于两种半抗原免疫制备的抗体,可建立腈菌唑胶体金检测方法,检出限满足国家标准限量要求,可应用于现场的快速筛查。     

胶体金粒径对氯霉素胶体金试纸条性能的影响

采用柠檬酸三钠法分别制备出粒径为20、30、40nm的3种胶体金溶液,并标记抗氯霉素(CAP)单克隆抗体,另分别制备出竞争法氯霉素胶体金试纸条,并且对各种粒径胶体金制备试纸条的工艺进行优化,比较各种试纸条的性能。结果发现,利用30nm的胶体金制得的试纸条检测限(消线)为3ng/mL,检测快速、稳定,而20、40nm的胶体金制得的试纸条检测限(消线)分别为7、9ng/mL,稳定性较差。30nm的胶体金制备的胶体金试纸条在稳定性、灵敏度方面都明显优于20nm和40nm。     

毒死蜱单克隆抗体制备及icELISA检测方法优化

目的制备毒死蜱单克隆抗体,建立icELISA(间接竞争酶联免疫吸附方法)检测方法并对其进行优化。方法以毒死蜱为基础物质,制备半抗原CPF-H1和CPF-H2,偶联蛋白制备人工抗原,进而通过免疫、细胞融合、筛选得到特异性的单克隆抗体,建立毒死蜱的icELISA检测方法,并对其分析条件进行优化。结果质谱鉴定结果表明毒死蜱半抗原制备成功;半抗原偶联蛋白,紫外全波长扫描鉴定人工抗原制备成功;免疫动物、细胞融合并制备单克隆抗体;建立了icELISA检测方法,优化得到最佳反应条件:PBST为标准品稀释液,包被抗原最佳稀释倍数为1:1000,抗体最佳稀释倍数为1:1000,一抗反应最佳时间为40 min,二抗反应最佳时间为30 min,制得毒死蜱标准曲线,毒死蜱对抗体的IC_(50)为73-25 ng/mL,线性范围IC_(20)~IC_(80)为32.52~260ng/mL,LOD为19.34 ng/mL。结论本研究为毒死蜱快速检测技术奠定了理论基础,对保障人们的身体健康具有重要的意义。     

胶体金免疫层析法同时检测果蔬中四种农药残留

目的：研制一种胶体金免疫层析四线卡,可同时检测果蔬中毒死蜱、氟虫腈、克百威、多菌灵4种农药残留。方法：以硝酸纤维素膜为载体,农药竞争抗原为包被抗原,胶体金为标记材料,制备胶体金免疫层析四线卡,并对标记抗体浓度、检测线包被浓度、样品提取剂、提取时间等参数条件进行优化,评价四线卡的灵敏度、特异性、稳定性和准确性。结果：优化后四线卡制备工艺参数中毒死蜱、氟虫腈、克百威、多菌灵的最适标记抗体浓度为3.2、2.4、3.2、3.2μg/mL,T₁、T₂、T₃、T₄抗原包被浓度分别为0.65、0.80、0.65、0.5 mg/mL。毒死蜱检出限为0.1 mg/kg、氟虫腈为0.02 mg/kg、克百威为0.02 mg/kg、多菌灵为0.05 mg/kg,除了克百威与丁硫克百威的交叉反应率为20%,毒死蜱、氟虫腈和多菌灵与结构类似物的交叉反应率均小于5%,在室温条件下可保存至少12个月。经验证,对60份果蔬样品检测结果与仪器法检测结果一致。结论：本研究制备的四线卡操作简便、准确度高、快速、稳定,可以用于果蔬中毒死蜱...     

食品安全抽检环节芹菜中10种有机磷农药的残留降解规律研究

目的 研究食品安全抽检环节芹菜中10种有机磷农药的残留降解规律.方法 以芹菜为基质,选择10种有机磷农药(乐果、毒死蜱、甲基对硫磷、杀螟硫磷、甲基异柳磷、喹硫磷、水胺硫磷、杀扑磷、三唑磷、伏杀硫磷)作为研究对象,采用加标后均质的制样方法制备样品,将农药残留检测结果通过拟合一级动力学模型预测农药的降解半衰期,研究抽检样品...     

基于拉曼光谱技术检测菠菜毒死蜱残留的初步研究

目的 基于拉曼光谱技术初步探讨菠菜表面有机磷农药毒死蜱的快速、无损检测新方法。方法 利用本研究自行搭建的拉曼光谱检测系统获取残留不同浓度毒死蜱农药的菠菜光谱曲线, 通过SG-5点平滑减小曲线噪声, 基于最小二乘法的10次多项式拟合法剔除菠菜荧光背景, 并对含有不同浓度毒死蜱农药的菠菜样品拉曼图谱进行比较分析。结果 特征归属为P=S振动的632 cm-1处的拉曼信号可识别菠菜表面毒死蜱农药残留, 其检测限为400 mg/kg, 而且拉曼特征波峰的相对强度与菠菜表面农药残留浓度存在较好的线性关系, 其相关系数为R2=0.92。结论 拉曼光谱技术有望实现叶片类蔬菜的农药残留的快速、无损、定量检测。     

基于拉曼光谱技术检测菠菜的毒死蜱残留

目的基于拉曼光谱技术初步探讨菠菜表面有机磷农药毒死蜱的快速、无损检测新方法。方法利用本研究自行搭建的拉曼光谱检测系统获取残留不同浓度毒死蜱农药的菠菜光谱曲线,通过SG-5点平滑减小曲线噪声,基于最小二乘法的10次多项式拟合法剔除菠菜荧光背景,并对含有不同浓度毒死蜱农药的菠菜样品拉曼图谱进行比较分析。结果特征归属为P=S振动的632 cm-1处的拉曼信号可识别菠菜表面毒死蜱农药残留,其检测限为400 mg/kg,而且拉曼特征波峰的相对强度与菠菜表面农药残留浓度存在较好的线性关系,其相关系数为R2=0.92。结论拉曼光谱技术有望实现叶片类蔬菜的农药残留的快速、无损、定量检测。     

果蔬中残留有机磷农药降解菌的选育及鉴定

为减少果蔬中的农药残留量,利用96孔板从长期喷洒农药的耕地土壤中筛选出一株能高效降解有机磷农药的菌株,并对其进行形态学及生理生化鉴定,提取其基因组并与Gen Bank上已提交的26S r DNA进行BLAST比对,结果表明,其归属于红酵母菌属(Rhodotorula sp.)。由MEGA6.0软件构建的系统发育树结果表明,该菌株与Rhodotorula mucilaginosa 26S r DNA序列一致性可达99%,结果与生理生化实验相一致。因此,确定该菌株为胶红酵母菌(Rhodotorula mucilaginosa),编号为RM-DY21。利用紫外分光光度法测定该菌株32 h内对毒死蜱(50 mg/L)降解率为70.04%。该菌株在以有机磷农药(毒死蜱、氧乐果和敌百虫)为唯一碳源的培养基中生长效果好,说明其对这三种农药均有降解效果,可以广泛降解有机磷农药。     

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