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 212 毫秒
1.
目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定河粉和米粉中米酵菌酸(bongkrekic acid, BA)的含量。方法试样经提取、净化、浓缩及过滤后,以0.1%甲酸水和乙腈作为流动相进行梯度洗脱,采用电喷雾离子源负模式检测,外标法定量。基于米酵菌酸色谱和质谱行为的研究,对其仪器测定条件进行优化,并对优化后的方法进行方法学验证。结果米酵菌酸在1~100μg/L浓度范围内线性良好,相关系数大于0.999。在2种基质不同加标浓度下,回收率80.6%~104.8%,相对标准偏差小于5%。米酵菌酸在2种基质中的检出限为0.1μg/kg,定量限为0.2μg/kg。结论方法灵敏度高、专属性好、准确可靠,适用于米粉和河粉基质中米酵菌酸的测定。  相似文献   

2.
建立了快速测定银耳中米酵菌酸的超高效液相色谱串联质谱分析方法。样品采用甲醇提取,混合强阴离子交换固相萃取柱(PAX)净化,UPLC BEH C18(2.1×100 mm,1.7μm)色谱柱分析,以10 mmol/L乙酸铵-乙腈为流动相,梯度洗脱,串联四级杆质谱多反应监测负离子模式检测,基质匹配外标法定量。结果表明,米酵菌酸在1.6μg/L~80μg/L线性范围内,相关系数(r)0.999 9,检出限0.5μg/kg,加标回收率82%~102%,相对标准偏差RSD≤8.5%。本方法快捷准确、灵敏度高,可用于银耳中米酵菌酸的确证方法。  相似文献   

3.
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BEHAmide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 建立的测定方法对各氨基酸分离效果及峰型良好,在0.5~10.0μg/mL线性范围内,相关系数(r)均大于0.998, 16种氨基酸在各自质量浓度范围内均呈现良好线性关系,方法检出限0.23~4.59 mg/kg。样品在3个添加水平(25、50、100 mg/kg)的平均加标回收率为78.1%~114.4%,相对标准偏差0.7%~6.6%。测定部分预包装柳州螺蛳粉生产厂采样的酸笋原料,各氨基酸含量为0~625.8 mg/kg。结论 该方法简便快捷、测定高效,可用于酸笋的多种氨基酸含量分析测定。  相似文献   

4.
目的 建立超声辅助-液液萃取-超高效液相色谱-串联质谱法快速测定米粉、河粉中毒样品中米酵菌酸的方法。方法 在称取适量已匀浆好的样品中,加入乙腈超声提取、离心后取上清液,过0.22 μm的微孔滤膜, 待测物经0.2%甲酸-乙腈流动相, 经Thermo Hypersil GOLD C18柱(2.1 mm×100 mm ×1.9 μm)分离,以0.2%甲酸-乙腈为流动相,用超高效液相色谱-串联质谱仪 ESI源、采用ESI离子源负离子多反应监测模式检测,外标法定量。结果 在优化的条件下,该方法该方法的线性范围为0.5~100 μg/L,相关系数r为大于0.99550.999,线性关系良好,血浆中米酵菌酸的检出限(LOD, S/N=3)为0.05 μg/L,定量限(LOQ, S/N=10)0.15 μg/L,河粉中米酵菌酸的检出限米粉和河粉中米酵菌酸的检出限均为(LOD, S/N=3)为0.01μg/kg,定量限(LOQ, S/N=10)均为0.03 μg/kg,样品加标回收率在71.081.0%~81.890.4%之间,相对标准偏差(RSD)≤8.65.5%。 结论 该方法一步提取净化,不需要更换溶剂和固相萃取,方法快速、灵敏、准确,可应用于米粉、河粉中的米酵菌酸的测定突发应急事件中包括生物样品和食品在内的中毒样品的检测,为临床诊断和救治提供可靠的依据。  相似文献   

5.
目的建立高效液相色谱-串联质谱法(highperformanceliquidchromatography-tandemmass spectrometry,HPLC-MS/MS)快速检测银耳中的米酵菌酸的方法。方法样品以甲醇提取后,超声振荡,离心分层,上清液用甲醇定容。使用空白基质液配置标准曲线对结果进行校正。在优化后的色谱及质谱条件下,采用(electronsprayionization,ESI)负离子模式进行电离,并通过多反应监测(multi-selectedreactionmonitoring,MRM)模式对目标化合物的定量离子和定性离子进行测定。结果米酵菌酸在0.50~50.00μg/L范围内线性良好,相关系数r为0.9996,3个浓度添加水平的平均回收率范围在80.6%~95.6%之间,相对标准偏差为4.98%~7.21%。方法检出限(limit of detection, LOD)为5.0μg/kg,定量限(limit of quantification, LOQ)为15.0μg/kg。结论该方法操作简便快速,回收率高、灵敏度高、精密度好,适合测定银耳基质中的米酵菌酸。  相似文献   

6.
建立WAX混合型弱阴离子固相萃取富集净化,高效液相色谱-二极管阵列检测器快速测定食品中米酵菌酸残留的方法。采用C18色谱柱(4.6 mm×250 mm,5 μm),以乙腈-甲醇-1%乙酸溶液(10∶62∶28,V/V)为流动相,以269 nm为分析波长,米酵菌酸在0.1~40 mg/L质量浓度范围内线性良好,相关系数r值大于0.999。本实验考察样品的提取条件及不同固相萃取小柱净化效果,结果表明,选择体积分数80%乙腈溶液为提取溶剂,超声提取30 min,WAX小柱富集、净化,效果最佳。方法检出限为0.03 mg/kg。通过不同样品加标验证,平均回收率为83.3%~95.6%,相对标准偏差不大于5%(n=6)。与GB/T 5009.189-2003《银耳中米酵菌酸的测定》方法相比,该方法精确灵敏、回收率高、前处理简单快速,适用于各种食品中米酵菌酸残留快速测定。  相似文献   

7.
建立了固相萃取-高效液相色谱测定食品中米酵菌酸残留的方法,并评估了米酵菌酸的膳食风险水平。以米粉、银耳、玉米粉、椰子发酵饮料为研究对象,样品经过1%乙酸-乙腈(V/V)提取后,采用Poly-Sery MAX强阴离子交换柱进行净化,Athena C18-WP(4.6×250 mm, 5 μm)分离,以甲醇:1%乙酸-水(80:20,V/V)为流动相,269 nm为定量波长,二级管阵列检测器分析。结果表明,在优化色谱条件下,米酵菌酸在0.01~2.0 μg/mL的质量浓度范围内线性良好,相关系数为0.9999;在4种基质中进行低、中、高3个水平加标,加标回收率在90.0%~104.0%,相对标准偏差<5%(n=6),检出限和定量限分别为2.0、6.7 μg/kg,该方法前处理简便快速,精确灵敏,回收率高,适用于各类食品中米酵菌酸含量的准确定量分析;膳食风险评估结果表明,米酵菌酸的膳食危害商值为0.0747,远低于临界值1,对消费者的膳食安全构成威胁的概率较低。  相似文献   

8.
建立漂浮有机液滴凝固液相微萃取法联合高效液相色谱测定食品中米酵菌酸。方法经过系统的优化后,确定了最佳萃取条件:以30 μL十二醇作为萃取溶剂、300 μL丙酮作为分散剂,供相溶液pH值为2,在室温下萃取时间为15 min。在最佳萃取条件下,米酵菌酸在0.5~10 ng/mL的浓度范围内线性良好,相关系数R2大于0.999,最低检测限为1.00 μg/kg,样品加标回收率为83.5%~98.6%,富集倍数约达200倍。该方法快速准确、绿色环保,适用于食品中米酵菌酸的检测。  相似文献   

9.
建立茶叶中多菌灵残留的高效液相色谱-串联四极杆质谱联用测定方法。该方法中样品经0.2 mol/L盐酸甲醇溶液(1∶1,υ/υ)超声提取,MCX固相萃取柱净化,以ZORBAX Eclipse XDB-C18色谱柱(3.0 mm×50 mm,1.8μm)分离,流动相为0.1%甲酸水和乙腈(梯度洗脱),电喷雾正离子MRM模式检测。该方法的检出限为1.0μg/kg,线性范围0.5μg/L~3 000μg/L,加标回收率为85.0%~96.0%,相对标准偏差为3.71%。  相似文献   

10.
目的建立全自动固相萃取-液相色谱-串联质谱法测定蜂蛹粉中链霉素及双氢链霉素含量的分析方法。方法样品经磷酸缓冲溶液提取,高氯酸沉淀蛋白后,采用watersHLB固相萃取小柱净化,以Protemix WCX色谱柱进行色谱分离,多反应监测模式测定,外标法定量。结果结果表明2种化合物在10~200μg/kg的浓度范围内线性关系良好,检出限为5μg/kg,定量限为10μg/kg。空白蜂蛹粉样品的3水平加标回收率为80.6%~93.5%,相对标准偏差为4.7%~8.8%。结论该方法适用于蜂蛹粉中链霉素和双氢链霉素残留的检测。  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.
16.
17.
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   

18.
<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   

19.
《印刷工业》2014,(11):95-95
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%.  相似文献   

20.
《印刷工业》2014,(8):103-103
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  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