离子色谱法测定饮用水中9种阴离子的含量

建立一种离子色谱检测方法,用于同时测定饮用水中9种阴离子。用离子色谱法,采用As19分离柱和AG19保护柱,柱温30℃,流速1.0 m L/min。9种阴离子都能达到基线分离,在0.005~10 mg/L的浓度范围内,各组分呈良好线性关系。平均回收率在91.5%~105.3%。本方法快速、简便、准确、灵敏,可满足生活饮用水和包装饮用水卫生标准检测要求。     

分析离子色谱法测定饮用水中痕量亚硝酸盐和溴酸盐

应用离子色谱法测定饮用水中痕量亚硝酸盐和溴酸盐。水样随着淋洗液进入到离子交换柱系统,分离出水样中的离子(亚硝酸盐、溴酸盐),并应用相关检测其分析其在水样中的含量。检出限约在0.09 μg/L,相对偏差均小于4.30%,回收率在97.20%以上。该方法有较高的准确度,实际应用价值高。离子色谱法作为一项液相色谱技术,充分利用了离子交换的原理,对样品中共存的多种离子进行分离、定性和定量~([1])。不同用途的水中阴离子的含量各异,本次研究就饮用水中亚硝酸盐、溴酸盐两种离子的含量进行测定。人类长期饮用亚硝酸盐含量为5.00 μg/L的饮用水时,患癌概率会大大提高;亚硝酸盐则是判断水体有无受到污染的关键指标。本文就离子色谱法检测水样的实际效果进行探讨,过程如下。     

毛细管区带电泳-间接紫外检测法测定饮用水中5种阴离子

目的建立毛细管区带电泳-间接紫外检测法测定饮用水中5种阴离子的新方法。方法样品无需滤膜过滤可直接进样。用未涂覆熔融石英毛细管(75μm×80 cm,有效长度为70 cm)作为分离柱。以20 mmol/L邻苯二甲酸、100 mmol/L二乙醇胺和0.5 mmol/L十六烷基三甲基溴化铵为分离缓冲体系。结果 Cl~-、NO_3~-、SO_4~(2-)、F~-和H_2PO_4~-这5种阴离子的校正峰面积与质量浓度分别在0.5～100.0、0.2～20.0、0.5～100.0、0.2～4.0和0.2～5.0 mg/L范围内呈线性相关,相关系数分别为0.998 8、0.999 9、0.999 7、0.999 7、0.999 8。检出限均为0.05 mg/L,定量限均为0.15 mg/L,方法精密度均小于5%(n=6)。低、中和高质量浓度加标回收率在81.6%～108.6%之间,相对标准偏差在0.6%～3.7%之间(n=6)。用本法分析了7份饮用水样品,并与离子色谱法的结果相比较,除矿泉水中Cl~-结果偏低外,其余基本吻合。结论本方法简单,所用试剂环保,为饮用水中5种阴离子的常规检测提供了一种新方法,但不适合测定水样中低浓度的Cl~-。     

离子色谱法测定包装饮用水中的溴酸盐

对包装饮用水中的溴酸盐含量的测定方法进行研究,在现行国标的基础上,优化了色谱测定条件,并进行了方法学考察。该方法在5.00~100μg/L范围内线性关系良好(r=0.999 8),方法检出限为0.031 8μg/L,回收率为99.9%~102.5%(加标浓度25.25,50.50和75.75μg/L),重复性(n=6)为0.35%。并对乐山地区超市包装饮用水进行随机抽样调查,试样测定值在1.55~6.91μg/L之间,按GB 19298—2014限量要求(0.01 mg/L),均无过量添加。离子色谱法测定包装饮用水中的溴酸盐具有操作简便,灵敏度、准确度高,分离效果好,重现性佳等特点,可有效满足检验检测部门对包装饮用水中溴酸盐的测定。     

离子色谱法测定饮用天然山泉水中9种阴离子

建立能同时直接进样测定饮用天然山泉水中9种阴离子(F-、ClO2-、BrO3-、Cl-、NO2-、ClO3-、Br-、NO3-、SO42-)的离子色谱法。选择美国戴安公司DIONEX ICS-900型离子色谱仪,以IonPac AS9-HC阴离子色谱柱为分析柱,IonPac AG9-HC阴离子保护柱,淋洗液为碳酸盐系统9.0 mmol/L Na2CO3,流速为1.0 mL/min,进样体积为500μL,电导检测器温度为30℃,以氮气作为保护气,抑制器抑制模式为自循环再生模式,抑制器电流为100 mA。该方法的标准曲线平均相关系数为r=0.999 6,平均回收率为91.1%~105.6%,RSD为0.38%~1.97%;对4个饮用天然山泉水样品进行检测,样品中9种阴离子的含量都在线性范围内。该法操作简单、快速、准确,灵敏度高、重现性好,适用于饮用天然山泉水中9种阴离子的直接测定。     

离子色谱法同时测定蛋白胨中5种阴离子

目的建立离子色谱法同时测定微生物培养基蛋白胨中5种阴离子——氯离子Cl~-、硫酸根离子SO_4~(2-)、正磷酸根离子PO_4~(3-)、三偏磷酸根离子P_3O_9~(3-)和碘离子I-含量的方法。方法样品用10mmol/LNaOH溶液溶解浸提,经固相萃取柱OnGuard II RP柱和Na柱去除有机物及阳离子,净化后直接用于目标离子的测定。色谱分离选用强亲水性阴离子交换柱(IonPac AS11, 4.0 mm 250 mm),以KOH为流动相进行梯度洗脱,流速为1 mL/min,于抑制电流为174 mA下用电导检测器检测。结果在35 min内完成5种阴离子的分离分析。该方法测定5种阴离子相关性好(r0.999),线性范围宽,检测限均1μg/mL,蛋白胨样品中目标物的平均加标回收率为99.6%～108.4%(n=9)。结论该方法实现了5种阴离子的同时测定,简单高效,灵敏度高,用于实际样品测定结果满意。     

离子色谱法测定昌都市江水中5种阴离子

建立了离子色谱法-电导检测器同时测定扎曲、昂曲与澜沧江水中F~-,Cl~-,Br~-,NO_3~-及SO_4~(2-)等5种阴离子。采用Dionex Ion Pac AS19分离柱和Ion Pac AG19保护柱,在16 min内完成阴离子分离和检测。分析条件:淋洗液为20 mmol/L KOH,流速为1.0 mL/min,柱温为30℃。阴离子的定性限和定量限分别为0.5~3.8μg/L和1.7~12.7μg/L,线性相关系数在0.999 0以上,氟离子、氯离子、溴离子、硝酸根和硫酸根回收率范围分别为97.1%~107.5%,91.3%~103.9%,97.4%~103.2%,94.8%~100.6%和93.8%~103.3%,相对标准偏差均小于3%(n=7)。该方法准确度好、精密度高、快速,适用于检测扎曲、昂曲与澜沧江水中5种阴离子含量。     

离子色谱法测定饮用水中的溴酸盐、亚氯酸盐、氯酸盐及常规阴离子含量

研究大体积直接进样化学抑制电导-离子色谱法同时测定饮用水中溴酸盐、亚氯酸盐、氯酸盐以及其他7种常规无机阴离子的分析方法。采用IonPac AS9-HC分离柱和IonPac AG9-HC保护柱,以12mmol/L Na2CO3溶液为淋洗液,流速1.0mL/min,一次进样100μL。结果表明:该方法 18min内能检测出10种阴离子,各离子加标回收率为93.0%～103.1%;标准曲线的相关系数为0.9993～0.9999,相对标准偏差为1.07%～4.98%。该方法具有灵敏、准确、快速等优点,在优化条件下将该方法用于测定昆明市自来水和多种市售瓶装饮用水,结果较满意。     

离子色谱法测定饮用水中溴酸盐含量的不确定度评定

采用离子色谱法测定饮用水中溴酸盐含量,进行不确定度分析,计算各个不确定度分量,得到合成标准不确定度为2.16×10~(-4)mg/L。该评定方法对提高饮用水中溴酸盐的检测准确度具有指导意义。     

离子色谱法测定包装饮用水中的亚硝酸盐

对包装饮用水中亚硝酸盐含量的测定方法进行研究,优化色谱条件,建立了梯度淋洗-离子色谱法测定包装饮用水中亚硝酸盐的方法。选用ThermoAS11-HC色谱柱,以6～70mmol/LKOH淋洗液梯度淋洗,抑制型电导检测器检测。结果表明:亚硝酸盐在0.00～2.00mg/L有良好的线性关系,相关系数(r)为0.9999;方法检出限为0.75μg/L;3个不同水平(0.15、0.30、0.60mg/L)的加标平均回收率为95.94%～97.61%,RSD值为0.87%～1.01%。该方法具有操作简便、分析快速、灵敏度高、重现性佳等优点,适用于包装饮用水中亚硝酸盐含量的检测。     

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