液相色谱-串联质谱法测定水产品中硝基呋喃类代谢物残留量前处理方法的改进

研究旨在缩短水产品中硝基呋喃类代谢物残留量检测时间，提高检测效率。方法：样品经过水浴衍生，乙酸乙酯提取，正己烷脱脂后，采用ThermoHypersilGOLDC18色谱柱，以甲酸乙腈-乙酸铵为流动相洗脱分离后，经过质谱分析，内标法定量。结果显示：四种硝基呋喃类药物(AOZ,AHD,AMOZ,SEM)能有效分离，本实验室所优化的液相色谱-串联质谱法测定水产品中硝基呋喃类代谢物残留量的前处理方法，对比国标方法大大缩短了分析时间，并符合较好的线性、回收率等质量控制参数。     

动物源食品中硝基呋喃类物质及其代谢物残留的检测技术研究

呋喃类物质由于它的强毒性和致癌的副作用,已引起世界各国的高度重视。由于呋喃类物质在动物体内稳定性较差,而其代谢物与组织蛋白结合可以形成稳定的化合物,故对于呋喃类物质代谢物的研究和检测的意义就显得更为重要。本文介绍了硝基呋喃类物质的基本种类,分为呋喃唑酮(furazolidone),呋喃西林(nitrofurazone),呋喃妥因(furantoin)和呋喃它酮(furaltadone),及相应的理化特性和目前国内外的应用情况。着重介绍了硝基呋喃类物质代谢物的种类,分为呋喃唑酮(AOZ)、呋喃它酮(AMOZ)、呋喃西林(SEM)和呋喃妥因(AHD),及其毒性和危害;目前各国常用的检测方法有液相色谱-紫外法(HPLC-UV)、液相色谱-质谱法(LC-MS)、液相色谱-串联质谱法(LC-MS/MS)和酶联免疫法(ELISA)。比较了各种方法的工作原理、适用范围以及各自的特点。重点介绍了酶联免疫法(ELISA)的基理、分析方法和注意事项。并就目前国内硝基呋喃类物质代谢物相关检测标准的不足,提出了建议。     

动物源性食品中硝基呋喃及其代谢物产物检测 方法研究进展

2006年十大食品安全事件中"大闸蟹致癌"事件引起人们关注,虽然后来证实为夸大其词,但是此次事件中涉及的致癌物质硝基呋喃代谢物的检测方法仍然引起检测行业的重视。本文介绍了硝基呋喃类药物及其代谢物的相关性质、硝基呋喃类代谢物的限量要求、检测标准、检测方法及各方法的检出限。呋喃类药物在动物食用组织中能快速代谢,不易被检测到,而硝基呋喃类药物的代谢产物可在动物可食组织中长时间稳定保留,所以检测的目标物一般为硝基呋喃类药物的代谢物。目前各国常用的检测方法有高效液相色谱-紫外法(HPLC-UV)、液相色谱-质谱法(LC-MS)、液相色谱-串联质谱法(LC-MS/MS)及酶联免疫法(ELISA),除此之外,还有分光光度法和原子吸收法,本文比较了各种方法在实际应用中的优缺点,探讨了在检测过程中的注意事项,其中包括影响衍生的条件、环境等。     

2013年陕西省动物源性食品中硝基呋喃的污染状况调查

目的建立动物源性食品中硝基呋喃代谢物的检测方法,对2013年陕西省动物源性食品中硝基呋喃的污染现状进行调查分析。方法按照代表性、适时性和随机性原则在全省范围内采集样品737份,样品经2-硝基苯甲醛衍生化,固相萃取柱净化后采用超高效液相色谱-串联质谱法定量分析。结果动物源性食品中硝基呋喃代谢物的总检出率为3.93%(29/737),鸡肉中的硝基呋喃代谢物的检出率最高(8.05%,14/174),4种硝基呋喃代谢物中呋喃它酮代谢物5-吗啉甲基-3-氨基-2-噁唑烷基酮(AMOZ)的检出率最高(2.04%,15/737)。结论陕西省动物源性食品在一定程度上受到了硝基呋喃的污染,应引起监管部门的注意,加强食品监督管理,保障食品安全。     

超高压液相色谱-串联质谱法同时测定鸡蛋中4种硝基呋喃代谢物残留

建立超高压液相色谱-串联质谱法(UPLC-MS/MS)同时测定鸡蛋中4种硝基呋喃代谢物的方法。方法 鸡蛋中与蛋白质结合的硝基呋喃代谢物经盐酸水解后,与邻硝基苯甲醛(2-NBA)反应,产生稳定的衍生物,用乙酸乙酯提取,4 ℃冷冻离心后取下层澄清液测定。待测物采用电喷雾电离正离子、多反应监测模式检测,基质内标法定量。结果 4种待测物浓度在0.1～50.0 μg/L范围内与其峰面积比值呈良好的线性关系,相关系数均不低于0.995,回收率范围为74.1%～97.6%,RSD＜13.4%。氨基脲(SEM)与1-氨基-乙内酰脲(AHD)最低检出限均为0.1 μg/kg,5-吗啉甲基-3-氨基-2-恶唑烷基酮(AMOZ)与3-氨基-2-恶唑烷基酮(AOZ)最低检出限均为0.05 μg/kg。结论 该方法具有样品前处理简单、灵敏度高、重现性好等优点,满足鸡蛋中4种硝基呋喃代谢物残留定量检测的要求。     

LC-MS/MS测定饲料中氯霉素残留量两种不同前处理方法的比较

GB/T 21108—2007《饲料中氯霉素的测定高效液相色谱串联质谱法》(方法Ⅱ)里关于饲料中氯霉素检测的操作方法较为复杂,容易造成实验误差。方法Ⅰ对其中的前处理做了改进,简化了步骤,方法简单、误差小,大大缩短检测时间。样品经方法Ⅰ与方法Ⅱ两种不同的前处理方法处理,LC-MS/MS的同步检测,比较标准工作曲线、精密度和回收率。从实验结果数据中可以判断这两种方法均切实可行,但方法Ⅰ比方法Ⅱ的精密度和回收率更高,且更方便和快捷。     

超高效液相色谱-串联质谱法测定酸笋中多种游离氨基酸含量

目的 建立超高效液相色谱-串联质谱法测定柳州螺蛳粉原料酸笋中苯丙氨酸、亮氨酸、异亮氨酸等16种游离氨基酸含量的方法.方法 匀浆后的样品用水作为溶剂超声提取、离心过滤后,采用BEH Amide色谱柱分离,经甲酸铵水溶液-乙腈体系梯度洗脱,超高效液相色谱-串联质谱仪以正离子扫描,多反应监测模式进行检测.结果 建立的测定方法...     

液相色谱串联质谱法测定氨糖软骨素片中硝基呋喃类代谢物残留

目的采用液相色谱串联质谱法测定氨糖软骨素片中的硝基呋喃类代谢物残留量。方法样品在酸性条件下(pH2)衍生16 h,经乙酸乙酯提取浓缩。经甲醇水溶液溶解过滤后,用液相色谱-串联质谱测定。试验过程中采用添加同位素内标法来补偿前处理过程中产生的损失。结果在0.5、1.0和2.0μg/kg 3个浓度水平上进行添加回收试验,4种代谢物的回收率范围为82.7～106.7%,相对标准偏差不大于12.3%,检出限均为0.5μg/kg。结论该方法具有良好的准确度、灵敏度和稳定性,可用于氨糖软骨素片中硝基呋喃类代谢物残留量的测定。     

超高效液相色谱-串联质谱法测定淡水鱼中硝基呋喃类代谢物残留

目的建立超高效液相色谱-串联质谱测法测定淡水鱼中呋喃它酮、呋喃妥因、呋喃唑酮和呋喃西林等硝基呋喃代谢物的研究方法。方法样品中加入同位素内标,经盐酸水解,用2-硝基苯甲醛衍生,乙酸乙酯液-液萃取净化后,超高效液相色谱-串联质谱仪测定,内标法定量。结果 4种硝基呋喃代谢物的检出限为0.07~0.25μg/kg;在0.1~10 ng/m L范围内线性相关系数r0.996;4种硝基呋喃代谢衍生物的加标回收率分别为94.0%~98.2%、84.0%~89.6%、94.0%~99.0%和75.4%~85.5%;相对标准偏差为2.5%~9.2%。应用建立的方法对48份淡水鱼进行测定,其中1份检出呋喃唑酮代谢物3-氨基-2-噁唑烷基酮(3-amino-2-oxazolidinone,AOZ),含量为0.45μg/kg。结论建立的方法选择性高、灵敏性强、准确度高,能满足淡水鱼中硝基呋喃类代谢物残留的高灵敏分析。     

超声波辅助衍生-液相色谱串联质谱法快速测定克氏原鳌虾中的硝基呋喃类代谢物残留

建立了克氏原鳌虾样品中4种硝基呋喃类代谢物残留检测的超声波辅助衍生-液相色谱串联质谱法。试验对比了超声波辅助衍生和恒温振荡衍生的效果,优化了色谱质谱条件以及定性定量离子对,确定了最佳试验条件。在优化的实验条件下,4种硝基呋喃类代谢物在0.5～50.0 ng/mL范围内线性良好,相关系数0.99,方法检出限为0.5μg/kg,在3个不同质量浓度的添加水平下,4种代谢物的平均回收率在93.3%～104.9%之间,相对标准偏差10%。采用实际样品对本文所建立的方法和国家标准检验方法对比,结果表明两种方法所测得的样品含量偏差较小,小于4.78%,本方法相较于国标方法更为简便快速,能显著缩短样品前处理时间,提高检测效率,在日常检测方面存在一定的优势,可为后续开展进一步的基础研究奠定基础。     

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.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.