首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
构建了一种快速检测单核细胞增生李斯特氏菌的适配体试纸条。以单核细胞增生李斯特氏菌核酸适配体为识别分子,纳米金为显色信号,基于双适配体夹心原理,制备了用于检测食品中单核细胞增生李斯特氏菌的适配体试纸条,并对制备条件如适配体浓度、胶体金溶液pH值、纳米金-适配体复合物和链霉亲和素-纳米金复合物的包被量等进行了优化。结果显示,在优化条件下,该试纸条对单核细胞增生李斯特氏菌的裸眼可视检测限为10~3cfu/mL,且具有很高特异性。可实现样品中单核细胞增生李斯特氏菌的快速定性检测。  相似文献   

2.
本文以建立志贺氏菌荧光纳米颗粒免疫层析法为目的。首先,制成志贺氏菌单抗-荧光纳米颗粒偶联物,以双抗体夹心模式制备志贺氏菌免疫层析试纸条。利用微型手持荧光检测仪读出质控线和检测线上的荧光信号,并利用荧光强度来半定量检测志贺氏菌。结果显示:用本研究建立的荧光纳米颗粒试纸条检测30株菌,对宋内志贺氏菌和福氏志贺氏菌呈阳性结果,其余菌株的呈阴性结果,试纸条灵敏度为9.0×104 CFU/m L。用志贺氏菌免疫层析试纸条和标准法检测60份样品,两种方法的总符合率为88.3%。结论:本研究成功建立了志贺氏菌的荧光纳米免疫层析检测方法,能够快速检测志贺氏菌,具有良好的特异性和灵敏性,便于开展现场快速检测。  相似文献   

3.
本研究以金黄色葡萄球菌为检测靶标,以核酸适配体为识别分子,基于双适配体夹心和侧流层析原理,构建了定性检测金黄色葡萄球菌的适配体试纸条,并对NaCl浓度、适配体浓度、纳米金-适配体包被量及捕获探针包被量等实验条件进行优化,获得适配体试纸条最佳制备条件。在优化条件下对试纸条的灵敏度、特异性进行分析测试,最后将试纸条对116份食品进行金黄色葡萄球菌检测,并与国标法(GB 4789.10-2016)对比验证。结果显示,适配体试纸条最佳制备条件为NaCl浓度为80 mmol/L、适配体偶联浓度为1 μmol/L、结合垫上纳米金-适配体的稀释体积比为1:2、捕获探针浓度为25 μmol/L。在最佳条件下,适配体试纸条对金黄色葡萄球菌的可视化检测限为2×103 CFU/mL,检测时间为5 min,且与其他食源性致病菌如鼠伤寒沙门氏菌、单增李斯特菌、大肠杆菌、阪崎肠杆菌、痢疾志贺氏菌等无交叉反应,具有较高的特异性。将本方法应用于食品中金黄色葡萄球菌的定性检测,检测结果与国标法完全一致。该方法简便快速、准确可靠、成本低,适用于食品样品中金黄色葡萄球菌的定性检测。  相似文献   

4.
目的 基于氧化铈修饰的金纳米棒(CeO2 modified Au nanorod, AuNR@CeO2)纳米酶构建纳米酶侧流免疫层析法(lateral flow immunoassay, LFIA), 并用以检测食品中肠炎沙门氏菌。方法 采用模板法制备AuNR@CeO2纳米酶, 对纳米酶的酶促活性进行考察。将AuNR@CeO2标记抗体作为信号探针进一步构建试纸条, 优化其关键参数, 并利用AuNR@CeO2纳米酶的酶促活性, 催化放大试纸条的比色信号, 最后将其用于奶粉中肠炎沙门氏菌的检测。结果 成功制备了AuNR@CeO2纳米酶, 在最优条件 下(即:2% BSA+0.05% Tween-20的样品垫缓冲体系、0.8 mg/mL的T线抗体质量浓度和4 μL的探针使用量), 该试纸条可以实现目标菌的特异性检测, 检出测限 低至103 CFU/mL, 信号放大后灵敏度提高了10倍, 在人工污染奶粉样品中也表现出良好的检测效果 检出限低至103 CFU/mL。结论 本研究所制备的试纸条无需复杂仪器和专业人员即可实现目标物的检测, 且具有易操作、便携、快速的特点, 通过更换抗体类型便可用于各类食品有害物质的检测。  相似文献   

5.
研制一种基于低噪声激发式荧光沙门氏菌免疫层析检测试纸条,用于沙门氏菌快速、高敏、兼顾定性及精准定量的检测。采用低噪声激发式荧光染料作为标记,采用免疫层析技术,制备靶向于沙门氏菌的免疫层析试纸条。检测时,采用专用便携式低噪声激发式荧光扫描仪分别扫描质控线和检测线,以检测线荧光强度检测值实现样本的定性及定量检测,并对免疫层析试纸条各项性能进行评价。低噪声激发式荧光沙门氏菌免疫层析检测试纸条制备成功,免疫层析试纸条性能检测结果显示,该试纸条特异性强、灵敏度高、检测限可达到0.5×10~3 CFU/mL,是一种新型快速高效稳定的检测方法。该免疫层析试纸条可适用于食品及病理样本中沙门氏菌初筛和即时检测。  相似文献   

6.
建立一种基于氧化石墨烯-金复合物的光热效应沙门氏菌渗滤试纸条的检测方法。制备了石墨烯-金纳米复合物,并将其与抗体偶联,在传统渗滤试纸条方法的基础上,优化了渗滤试纸条的各项试验条件以及激光照射时长。采用目测法及光热效应温差法检测沙门氏菌的最低检测限分别为2.4×10~4 CFU/m L及2.4×10~3 CFU/m L。绘制了石墨烯-金纳米复合物光热效应渗滤试纸条方法检测沙门氏菌的标准曲线,并得到线性回归方程:y=0.754x-2.09,R~2=0.971。  相似文献   

7.
本文研究了胶体金免疫层析试纸条快速定量检测猪肝中喹乙醇残留的方法。利用胶体金免疫层析技术,制备了喹乙醇胶体金试纸条,检测了其特异性,并建立了T/C比值法进行定量检测猪肝中喹乙醇的残留。制备的试纸条可以在15min内完成定性和定量检测,与卡巴氧、乙酰甲喹和3-甲基-喹噁啉-2-羟酸几乎无交叉反应。当肝中喹乙醇质量浓度在1200ng/mL范围内,试纸条有较好的线性关系,最低检测限为6.83ng/mL。阴性加标实验结果表明,喹乙醇浓度在25、50、100ng/mL时,试纸条的回收率在90.9%105.0%之间。   相似文献   

8.
本文研究了胶体金免疫层析试纸条快速定量检测猪肝中喹乙醇残留的方法。利用胶体金免疫层析技术,制备了喹乙醇胶体金试纸条,检测了其特异性,并建立了T/C比值法进行定量检测猪肝中喹乙醇的残留。制备的试纸条可以在15min内完成定性和定量检测,与卡巴氧、乙酰甲喹和3-甲基-喹噁啉-2-羟酸几乎无交叉反应。当肝中喹乙醇质量浓度在1~200ng/mL范围内,试纸条有较好的线性关系,最低检测限为6.83ng/mL。阴性加标实验结果表明,喹乙醇浓度在25、50、100ng/mL时,试纸条的回收率在90.9%~105.0%之间。  相似文献   

9.
闫灵芝 《食品工业科技》2021,42(11):397-404
免疫层析试纸条技术(Immunochromatographic Test Strip,ICTS)结合了色谱分析的分离能力和免疫分析的特异性,具有操作简单,检测快速以及价格低廉的特点,已成为食品安全快速检测领域研究的热点。传统的ICTS是以胶体金作为信号标记材料,但是胶体金试纸条检测灵敏度较低,只适用于定性和半定量检测。为了提升试纸条的检测性能,研究者做了大量的努力。本论文介绍了传统的胶体金试纸条的检测基本原理,并对近年来开发的试纸条检测新技术进行综述,同时也提出该项技术目前所存在的局限性并提出了未来的发展方向,以期为试纸条的进一步开发利用提供一定的文献支持。  相似文献   

10.
目的:为探索花状纳米金(Gold nanoflowers,AuNFs)在免疫层析方法中应用的可行性,并探究其在果蔬样品中的应用。方法:使用AuNFs、球状金(Gold nanospheres,AuNSs)分别和苯醚甲环唑单克隆抗体制备免疫探针。优化反应体系,构建苯醚甲环唑(Difenoconazole,DIFE)免疫层析试纸条(immunochromatographic strip,IGTS)。验证该试纸条的检出限、特异性、准确性和精密度,并对果蔬样本进行检测。结果:以AuNFs为探针制备的试纸条检出限为0.05 mg/kg,检测限比以AuNSs为探针制备的试纸条检测限提高10倍,检测时间为15 min,与其他三唑类农药无交叉反应,假阴性率为0,假阳性率为3.75 %,稳定性良好。结论:以AuNFs为探针制备的试纸条性能良好,可以有效提升检测限,可准确检测果蔬中苯醚甲环唑含量是否超标。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
17.
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.  相似文献   

18.
19.
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.  相似文献   

20.
<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  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号