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1.
目的为研究不同消解方法对水产品中重金属元素测定的影响,找到最佳的前处理方法。分别采用高压消解罐消解、微波消解和湿法消解3种方法对紫菜(GBW10023)、扇贝(GBW10024)、大虾(GBW10050)等成分分析标准物质进行前处理。方法在电感耦合等离子体质谱(ICP-MS)优化条件下,测定3种标准物质3种消解方法的9种元素(Pb、Cd、Cr、As、Sn、Ni、Cu、Mn、Sr)含量,与标准参考值做对比,并测定各元素的回收率。结果 3种消解方法的测定结果基本在参考范围内,消解效果均较为理想,而微波消解法消解最彻底且消解液澄清,所受环境干扰最小,测定值更接近参考值,回收率也基本在90%~105%之间,较为理想;紫菜标物的湿法消解和高压消解罐消解法中均有剩余残渣;且湿法消解的回收率结果较不理想;9种元素标准曲线的线性关系较好,相关系数均大于0.999,仪器灵敏度、精准度较高。结论综合比较认为,微波消解法更适合扇贝、大虾、紫菜等水产品中无机元素测定的前处理要求。  相似文献   

2.
微波消解ICP-AES法测定婴幼儿配方乳粉中9种微量元素   总被引:3,自引:3,他引:0  
本文采用微波消解-电感耦合等离子体原子发射光谱法(ICP-AES)同时测定了婴幼儿配方乳粉中K、Na、Ca、Mg、Fe、Mn、Cu、Zn、P的微量元素含量。对使用仪器的工作参数进行了最佳的优化,测定婴幼儿配方乳粉的精密度和回收率,方法的精密度RSD为1.9%~5.3%之间,回收率为94%~110%之间。方法用于分析国家一级标准参考物质GBW10018(鸡肉)、GBW10017(奶粉),被测元素测定值与标准值或参考值吻合。  相似文献   

3.
建立电感耦合等离子体质谱(inductively coupled plasma-mass spectrometry,ICP-MS)的同时测定母乳中K、Ca、Na、Mg、P、Cu、Mn、Zn、Fe、Se共10 种矿物元素的分析方法。以浓硝酸和双氧水为混合试剂,采用密闭高压消解技术对母乳样品消解后,用ICP-MS检测,利用动态反应池技术有效地消除了分析过程中质谱的干扰,选取Rh作为内标元素校正基体效应和信号漂移。标准曲线用外标法定量,以相对标准偏差考察方法的重复性,以标准物质考察方法的准确性。实验测定的10 种元素线性回归方程的相关系数均大于0.999 0,回收率范围为80.00%~118.19%,对照分析的奶粉成分分析标准物质(GBW10017)和脱脂奶粉成分分析标准物质(GBW08509)的K、Ca、Na、Mg、P、Cu、Mn、Zn、Fe、Se测定值均在标示值范围内,相对标准偏差均小于10.0%。结果表明,实验方法具有较好的准确度和精密度,适用于测定批量母乳的矿物元素。  相似文献   

4.
采用微波消解前处理,电感耦合等离子体质谱法(ICP-MS)测定食用菌中铅、砷、汞、镉、铬、铜、锰、锌和镍的含量。试验表明,铅、砷、镉、铬等元素在0~500 ng/mL浓度范围内线性良好,Hg在0~2ng/mL浓度范围内线性良好,各元素的线性方程相关系数均大于0.999,检出限在0.012~0.95 ng/mL之间,测定所有元素相对标准偏差均小于5%,加标回收率在89.5%~110.0%之间。同时,四种标准物质GBW08521,GBW(E)080684,GBW07605(GSV-4)和GBW10017中各元素测定值均在标准值范围之内,由此说明该方法能够简单、快速、灵敏、准确测定食用菌中重金属元素的含量。  相似文献   

5.
《食品与发酵工业》2019,(16):281-285
建立快速石墨消解-电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP-MS)测定海菜中13种元素含量的方法。通过单因素试验优选海菜快速石墨消解最佳条件,以~(45)Sc、~(72)Ge、~(115)In、~(209)Bi为内标,用ICP-MS同时测定海菜中13种元素。海菜快速石墨消解最佳条件为,HNO_32.0 mL,H_2O_21.0 mL,温度120℃,时间20 min。Na、Mg、K、Ca在0~10 mg/L,Mn、Ni、Cu、Zn、As、Sr、Cd、Ba、Pb在0~0.3 mg/L线性良好,相关系数均≥0.999 5。13种元素的检出限为0.000 6~0.670 1 mg/kg,定量限为0.002 0~2.233 8 mg/kg,相对标准偏差为0.34%~5.31%,回收率为87.6%~108.5%。采用该法处理国家标准物质螺旋藻(GBW10025),测定结果在参考值范围内。该法简单、快速、准确、可靠,可用于植物样品中多元素分析的样品前处理和测定。  相似文献   

6.
采用微波消解前处理,电感耦合等离子体质谱法(ICP-MS)测定部分香辛料中铅、砷、镉、铬、铜、锰、锌和镍的含量。测定结果显示各元素线性范围均为0~500ng/mL,线性方程相关系数均大于0.9995,各元素检出限在0.009~0.42ng/mL之间,相对标准偏差均小于5%,低、中、高质量浓度标准溶液加标回收率在88%~109%之间,选择的3种标准物质GBW08521、GBW(E)080684和GBW07605(GSV-4)的各元素测定值均在标准值范围之内,由此说明该方法能够简单、快速、灵敏、准确测定香辛料中重金属元素。  相似文献   

7.
本文建立了电感耦合等离子体质谱同时测定出口蔬菜中Mg、Ti、V、Cr、Mn、Fe、Ni、Cu、Zn、As、Se、Cd、Tb、Hg和Pb共15种无机元素的分析方法。样品在硝酸过氧化氢体系中经微波消解后直接上样分析,采用氦气碰撞模式消除了多原子离子质谱干扰,以Sc、Rh、In、Ir作为内标元素校正了质谱分析中基体效应并补偿了信号漂移。结果表明:测定质量浓度在0~50 mg·kg-1范围内,各元素呈现良好的线性关系,r≥0.9995;检出限为0.003~37.21μg·kg-1。选择国家标准物质豆角(GBW10021)、芹菜(GBW10048)和大葱(GBW10049)验证方法的可靠性,待测元素测定结果均在标准值允许范围内,日间相对标准偏差(n=6)在1.4%~19.4%之间。应用该方法测定了连云港蔬菜基地10种出口蔬菜,结果发现As、Cd、Pb、Cr、Hg含量均符合国内外相关标准中的限量要求。样品的测定结果为掌握连云港出口蔬菜中各种元素的含量水平,指导基地蔬菜的种植与出口提供了理论依据。  相似文献   

8.
研究了同时准确测定的水产品中铅、砷、镉、铬、镍元素方法。采用微波消解仪对样品进行前处理、电感耦合等离子体质谱测定5种元素含量。实验表明,所有元素标准曲线的线性范围均在0~200ng/mL之间,线性方程相关系数(r)均大于0.9995,检出限为0.012~0.091ng/mL,RSD<5%,加标回收率在86.1%~115.5%之间,并以标准物质GBW08571、GBW08521、GBW07605(GSV-4)对方法进行了评价,各元素测定值均在标准值范围之内。该方法具有简单、快速、灵敏、准确的优点,能够对水产品中的重金属元素进行测定。  相似文献   

9.
建立微波消解-电感耦合等离子体质谱法测定油茶籽油中的Pb、Cd、Cr、Cu、As五种重金属元素的方法。优化微波消解条件和仪器测定条件,选择同位素187Re、103Rh、45Sc作为内标元素来校正基体带来的干扰。方法的检出限在0.36~1.64μg/kg,加标回收率在84%~111%之间,精密度RSD在1.6%~7.6%(n=5)之间。采用该方法对茶叶标准样品(GBW10016)和苹果标准样品(GBW10019)进行验证,测定值均在保证值范围内。本方法具有快速、准确、可靠、灵敏度高。  相似文献   

10.
目的 建立电感耦合等离子体质谱法快速测定玫瑰茄茶汤中14种元素的分析方法。方法 采用密闭高压消解法消解玫瑰茄样品, 沸水溶出法浸泡玫瑰茄, 利用电感耦合等离子体质谱法准确测定其中的14种元素(Pb、Cd、As、Cr、Mn、Cu、Zn、K、Na、Ca、Mg、Fe、Se、Co)的含量并计算各元素的沸水溶出率。结果 14种元素在0.05~100 μg/L范围内线性关系良好, 方法用于标准物质绿茶(GBW 10052)的测定, 测定值均在标示值范围内。结论 该方法准确快速, 适用于玫瑰茄茶汤中14种元素的快速检测。  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.
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.  相似文献   

16.
Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH3CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH2PO4-20.6 mM Na2B4O7 buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.  相似文献   

17.
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   

18.
An investigation is described in which various polyfunctional compounds were applied to wool in attempts to stabilize the temporary improvements in wrinkle-recovery brought about by ‘annealing’. Several reactive systems involving formaldehyde were found to produce the desired permanently improved wrinkle-recovery.  相似文献   

19.
20.
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   

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