酶联免疫检测法测定水产品中残留氯霉素的研究

研究了水产品中残留氯霉素的检测方法。采用酶联免疫检测法(ELISA)测定鱼、虾类水产品中残留氯霉素含量,结果表明:检出限为0.009ng/mL,变异系数为3.0%,样品测定的相对偏差为3.4%～7.1%,回收率为92.5%～102.0%。在0.025～2.00ng/mL测定范围内呈良好的线性关系,相关系数R=0.9993。用ELISA测定水产品中氯霉素残留量,实验结果令人满意。     

液液萃取-液相色谱-串联质谱法测定蜂蜜中氯霉素

目的建立液相色谱-串联质谱法检测蜂蜜中氯霉素残留量的方法。方法试样前处理采用液液萃取,以甲醇 水(71 29体积分数)为流动相,用Zorbax Eclipse XDB C18柱进行分离,以氘代氯霉素作为内标,采用负离子方式,液相色谱-电喷雾串联质谱法进行测定。结果平均回收率为93.0%-98.2%,相对标准偏差小于8%。采用空白蜂蜜基质制作校正曲线,蜂蜜中氯霉素检测的线性范围为0.01-1.00μg/kg,定量检测下限为0.01μg/kg。结论方法灵敏、准确、快速,能满足蜂蜜中氯霉素的监督检测。     

肠衣中氯霉素残留量检测的研究

研究了应用酶联免疫反应方法(ELISA)，检测进出境肠衣中氯霉素残留置的制样和运用德国R-Biopharm公司的氯霉素残留测定试剂盒测定氯霉素残留量的具体操作方法及注意事项，可将氯霉素检测下限达到0.1μg/kg。     

免疫亲和柱-高效液相色谱法检测乳制品中氯霉素

建立免疫亲和柱富集净化、高效液相色谱-紫外法快速测定牛奶和奶粉中氯霉素残留物。样品用乙酸乙酯提取,经免疫亲和色谱柱纯化,应用液相色谱-紫外法检测。结果表明,牛奶和奶粉添加氯霉素,回收率为79.6%~108.6%,变异系数小于10%;方法检测灵敏度0.1μg/L。该方法能够特异性的纯化牛奶和奶粉样品中的氯霉素,免疫亲和柱(IAC)净化是一种简单,快速,准确的方法。     

养殖对虾中氯霉素残留的放射免疫分析

采用放射免疫分析法测定了湛江市水产市场3份新鲜养殖对虾及2份出口养殖对虾氯霉素残留量。结果表明,本方法的检测限量为0.15ppb,3份新鲜养殖对虾体内氯霉素残留量均大于0.15ppb,2份出口养殖对虾氯霉素残留量均小于0.15ppb。提示放射免疫分析法可作为水产品中氯霉素残留量的有效检测手段。     

应用酶联免疫法检测鱼肉、蜂蜜中氯霉素的残留量

检测鱼、蜂蜜中氯霉素残留,以评价试剂盒性能为目的。用间接竞争酶联免疫分析法(ELISA法)对鱼肉、蜂蜜中的氯霉素残留量进行了测定。结果表明,标准曲线的R2为0.9943,线性方程y=-0.3668x+0.4353,IC50为0.71μg/L,线性范围为0.05～4.05 ng/mL。鱼肉和蜂蜜中的检测限分别为0.126μg/kg和0.081μg/kg。鱼肉和蜂蜜的添加回收率分别大于88.1%和85.5%,批内变异系数分别小于15.8%、13.6%,批间变异系数小于15.5%、12.3%。与氯霉素琥珀酸钠的交叉反应率为152.63%,与其他药物的交叉反应率均小于0.01%。该法测定氯霉素灵敏准确,重复性好,特异性高,适合用于检测鱼肉、蜂蜜中的氯霉素残留。     

奶糖中氯霉素残留的分析

为了探查以乳作为辅料的食品是否存在抗生素残留现象,对市场中15种奶糖样品进行氯霉素检测。在检测方法上,分别采用了微生物测定法、免疫测定法及液质联用测定法,并对检测结果进行分析。结果显示:经微生物测定法检测,15种样品均为氯霉素阴性。而采用免疫测定法检测,氯霉素含量大于0.025μg/kg的样品数为12种,占样品总数的80%。根据免疫测定法的测定结果,选取其中3种氯霉素含量较高的样品,进一步采用液质联用测定法进行验证,测定结果与免疫测定法相比基本符合。结果表明:通过对氯霉素的检测,证实了一些奶糖中存在抗生素残留现象,揭示了其可能的健康安全隐患,检测结果还可以为相关食品检测标准的完善提供参考依据。     

虾肉中氯霉素的UPLC/MS-MS检测方法研究

建立虾肉中氯霉素残留的超高压液相色谱/质谱/质谱测定方法.用乙酸乙酯提取,蒸干后用蒸馏水溶解残渣,直接过Oasis HLB小柱净化,洗脱液收集吹干后用流动相定容,用UPLC/MS/MS测定.在0.5 ng/mL～10ng/mL浓度范围内,该方法的回收率为71.2%～110%.批内变异系数为6.3%～16.8%.批间变异系数为14.3%～19.7%.该方法测定虾肉中氯霉素的最低检测限为0.1 ng/L.     

养殖对虾中氯霉素残留的放射免疫分析

采用放射免疫分析法测定了湛江市水产市场3份新鲜养殖对虾及2份出口养殖对虾氯霉素残留量。结果表明,本方法的检测限量为0.15×10-12,3份新鲜养殖对虾体内氯霉素残留量均大于0.15×10-12,2份出口养殖对虾氯霉素残留量均小于0.15×10-12。提示放射免疫分析法可作为水产品中氯霉素残留量的有效检测手段。     

液质联用内标法测定饲料中氯霉素残留量的不确定度评估

利用液相色谱质谱联用仪,以氯霉素-D5为内标物,测定饲料中氯霉素的残留量,并进行不确定度的评估.结果表明,量化各不确定度分量得出饲料中氯霉素残留量为:X=(5.01±0.98)μg/kg(k=2);同时得出影响氯霉素检测结果不确定度的主要来源是标准系列溶液操作、样品前处理、样品重复测定和标准曲线拟合.     

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