玉米赤霉烯酮时间分辨荧光试纸条的制备及特性研究

研究制备一种基于时间分辨荧光免疫层析法的玉米赤霉烯酮(ZEN)快速定量检测试纸条.采用铕纳米微球作为荧光探针,标记抗ZEN的单克隆抗体,应用竞争抑制原理建立免疫层析定量方法并对其进行方法学考核.结果表明:ZEN荧光试纸条的灵敏度为0.1 ng/mL,线性范围为0.1～5.0 ng/mL,玉米、小麦阴性样品的加标回收率在...     

胶体金免疫层析法快速检测牛奶中环丙沙星残留

针对牛奶中恩诺沙星的代谢物环丙沙星残留的问题,该研究开发一种胶体金试纸条快速检测牛奶中的环丙沙星残留。研究制备环丙沙星包被抗原,对环丙沙星抗体进行表征,优化胶体金标记条件,选用最佳标记pH和最佳蛋白添加量,以硝酸纤维素膜为固相载体,环丙沙星包被抗原为检测带(T带),羊抗兔二抗为质控带(T带)。依据免疫竞争法原理,建立胶体金免疫层析试纸条快速检测牛奶中环丙沙星的方法,方法检出限为6.25 ng/mL,对牛奶样品的检出限为12.50 ng/mL。样品前处理方法简单,在10 min内即可目测判断结果。     

玉米赤霉烯酮时间分辨荧光试纸条的制备及特性研究（网络首发、推荐阅读）

研究制备一种基于时间分辨荧光免疫层析法的玉米赤霉烯酮（ZEN）快速定量检测试纸条。采用铕纳米微球作为荧光探针,标记抗ZEN的单克隆抗体,应用竞争抑制原理建立免疫层析定量方法并对其进行方法学考核。结果表明：ZEN荧光试纸条的灵敏度为0.1 ng/mL,线性范围为0.1~5.0 ng/mL,玉米、小麦阴性样品的加标回收率在93.45%~112.20%之间,对于同一个样品5次重复测定的变异系数小于15%。ZEN快速定量检测试纸条具有灵敏度高、反应时间短、准确定量、稳定性好等技术特点,适用于谷物及制品中玉米赤霉烯酮的快速定量检测。     

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。     

荧光免疫定量法即时检测谷物中黄曲霉毒素B1

目的 基于时间分辨荧光免疫层析技术,研制快速定量检测试纸条,用于粮谷物中黄曲霉毒素B1的检测。方法 以荧光微球为标记物,采用DNP独立质控体系和竞争法检测原理,构建了粮谷物中黄曲霉毒素B1荧光免疫定量即时检测（point-of-care testing ,POCT）方法。评价其准确度、重复性、特异性、与仪器确证方法符合度。结果 该方法最适条件为：pH7.8硼酸盐（BB）活化,pH7.5磷酸盐（PB）偶联,微球抗体质量比为5:4,抗原抗体质量比为50:1。检测限在0.299 ng/g -0.997 ng/g之间,定量限在0.544 ng/g -2.663 ng/g。代表性样本准确度为92.2%-111%,重复性为3.2%-7.5%。除与黄曲霉毒素B2有交叉反应（6.1%）,与其他类似物无（<0.1%）。该法检测结果与仪器确证法一致性好,在-12.5%—15.9%之间。结论 提供了一种准确、快速、定量、灵敏、便捷、适合现场检测粮谷物中黄曲霉毒素B1的时间分辨荧光免疫检测试纸条。     

荧光微球免疫层析法定量检测牛乳中酪蛋白

目的研究用荧光微球免疫层析法定量检测牛乳中的酪蛋白。方法本文以酪蛋白为抗原,免疫新西兰大白兔制备抗酪蛋白的多克隆抗体,将纯化后的多克隆抗体通过EDC介导法与荧光微球进行偶联,将滤纸、样品垫、结合垫、NC膜和吸水纸组装成试纸条,用此荧光微球免疫层析法定量检测牛乳中的酪蛋白。结果试纸条在25 min内就能判定结果,最低检测限为100 ng/mL,该方法与BSA、OVA均无交叉反应,具有很好的特异性。检测酪蛋白浓度为100.0、500.0、1000.0 ng/mL的样品,试纸条的批内回收率分别为(89.03±5.2)%、(93.47±6.9)%和(91.2±7.8)%,批间回收率分别为(87.69±6.2)%、(92.73±8.3)%、(89.82±8.5)%。结论初步建立了一种快速、方便、高灵敏度的荧光微球免疫层析方法用以检测牛乳制品中的过敏原——酪蛋白。     

谷物中玉米赤霉烯酮高灵敏时间分辨荧光免疫层析定量法的建立

建立了一种快速检测谷物中玉米赤霉烯酮的时间分辨免疫层析定量检测方法。对荧光微球与抗体制备过程、抗原抗体反应比例、样本前处理过程等实验条件进行优化，在最佳实验条件下，评价试纸条的检测限、准确度、重复性、特异性及稳定性。试纸条最佳研制条件：活化缓冲液为pH5.0 MES,标记缓冲液为pH7.2 HEPES,EDC用量为100μg,抗体标记量为100μg,膜T线0.6 mg/ml, C线0.25 mg/ml包被，微球偶联物稀释6倍。确定60%甲醇水和样本按质量体积比1∶5混匀提取时间5 min。通过Logistic曲线四参数拟合，R²均为0.99,在5～200 ng/g范围内具有较好的线性关系，玉米、小麦、小米、大米样本的检出限分别为4.24、1.28、1.63、1.49 ng/g。回收率在82.00%～113%,变异系数均小于15%。与其他真菌毒素的交叉反应率均小于1%,37℃放置21 d基本稳定。选择20份样本与仪器确证方法比较，结果一致性好。所制备的试纸条具有较好准确性、重复性、特异性及热稳定性，该方法操作简单、快速，结果准确、可视化，适合于大批量样本的快速筛查。     

荧光免疫层析法结合免疫磁珠分离技术快速检测单增李斯特菌

为建立单增李斯特菌简单快速、灵敏度高和特异性强的检测方法,本研究以抗单增李斯特菌单克隆抗体偶联磁珠制备免疫磁珠;以羧基荧光微球标记的抗单增李斯特菌多克隆抗体及鼠IgG为标记抗体,抗单增李斯特菌多克隆抗体和羊抗鼠二抗分别作为检测线和质控线制备荧光免疫层析试纸条。将免疫磁珠分离与荧光免疫层析法相结合应用于单增李斯特菌的现场快速检测中。结果表明:荧光免疫层析试纸条对纯培养单增李斯特菌的检测限为4×105CFU/mL,联合检测方法10倍、100倍浓缩时,检测限分别为4×104CFU/mL和1×104CFU/mL。联合检测体系特异性较好,与实验室保存的10株细菌无交叉反应。人工污染样本检测限为1×104CFU/mL,同纯培养物相比检测灵敏度并没有降低。本方法的建立对于食品中单增李斯特菌的现场快速检测具有重要意义。     

量子点微球荧光免疫层析定量检测水产、畜禽肉组织中恩诺沙星

目的 建立一种快速定量检测水产、畜禽肉组织中恩诺沙星的新方法学。方法 以量子点荧光微球为新型标记探针,通过参数优化,制备获得量子点荧光微球免疫层析试纸条;进一步以T/C比值法建立定量检测恩诺沙星的新方法。结果 在最优条件下,该试纸条检测缓冲液中恩诺沙星半数抑制浓度为1.035 ng/mL,最低检测限为0.125 ng/mL;检测水产、畜禽肉组织中恩诺沙星的定量检测范围为8.75~560 μg/kg,半数抑制浓度为72.45 μg/kg,加标回收实验显示该方法定量检测组织样本中恩诺沙星的回收率在83.03~124%之间,变异系数小于15%,检测15个实际含有恩诺沙星的水产以及畜禽肉组织样本,其结果与LC/MS/MS方法检测结果高度一致;此外,加速保存实验结果显示该试纸条在室温下可保存一年。结论 本研究以量子点荧光微球为新型标记探针,构建了高灵敏定量检测恩诺沙星的新方法,实现了水产、畜禽肉组织中恩诺沙星的简单、快速、定量分析。     

时间分辨荧光免疫层析法定量检测稻谷中的镉

本研究制备了一种用于稻谷中镉检测的时间分辨荧光免疫层析定量检测卡。采用铕纳米微球作为荧光探针,标记抗Cd-EDTA的单克隆抗体,基于竞争抑制原理建立免疫层析定量方法并对其进行方法学研究。结果表明：定量检测卡的灵敏度为0.088 ng/mL,标准曲线线性范围为0.1ng/mL～5.0 ng/mL,检出限和定量限分别为0.026 mg/kg和0.064 mg/kg,对有证标准物质的正确度在81.0%~91.7%之间,对实际样本的检测与ICP-MS检测结果一致性较高。该法重复性较好,变异系数在10%以内。结果显示,该法灵敏度高、操作简便、成本低廉,因此,非常适合基层单位大量样本的快速初步筛查。     

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