超高效液相色谱-串联质谱法快速检测水产品中喹乙醇及其代谢物3-甲基-喹噁啉-2-羟酸的残留

建立了水产品中喹乙醇(OQX)及其代谢物3-甲基-喹噁啉-2-羟酸(MQCA)的超高效液相色谱串联质谱快速测定方法。试样经乙酸乙酯+乙腈(1+1,V/V)液液萃取提取和净化后,BEH C18UPLC进行分离,多反应选择离子检测。方法的回收率和变异系数分别在62.5%~91.4%和2.6%~11.8%之间。本方法对水产品中喹乙醇和3-甲基喹噁啉-2-羧酸的检测限均为1.0μg/kg。     

超高效液相色谱-串联质谱法测定纯牛奶中喹乙醇及其代谢物

目的建立可靠的前处理方法 ,采用超高效液相色谱-串联质谱法检测纯牛奶中喹乙醇及其代谢物3-甲基-喹噁啉-2-羧酸(MQCA)。方法样品经盐酸水解,乙腈-乙酸乙酯(1∶1,V/V)提取,分析了直接浓缩及分别经PAX、PEP固相萃取小柱净化、富集的结果 ;以乙腈-0.05%氨水为流动相,经Inertsil ODS-3色谱柱(2.1 mm×100 mm,3μm)分离,采用多反应监测正离子模式进行定性及定量分析。结果直接浓缩具有较好的回收率,喹乙醇的方法检出限为0.06μg/kg,方法定量限为0.20μg/kg,在0.20、1.00、5.00μg/kg 3个加标水平下回收率分别为69.8%、111%、97.4%;MQCA的方法检出限为0.02μg/kg,方法定量限为0.10μg/kg,在0.10、1.00、3.00μg/kg 3个加标水平下回收率分别为75.8%、112%、117%。结论该检测方法适用于纯牛奶中喹乙醇及其代谢物残留的检测。     

液相色谱-串联质谱法测定猪肝中喹乙醇残留标示物3-甲基喹噁啉-2-羧酸

目的 建立猪肝中喹乙醇残留标志物3-甲基喹噁啉-2-羧酸(MQCA)的液相色谱-串联质谱(HPLC-MS/MS)快速检测方法。 方法 猪肝匀浆,加乙腈提取。提取液用Oasis MAX固相萃取柱净化,2%的甲酸乙酸乙酯溶液洗脱。洗脱液氮气吹干,用0.1%甲酸-甲醇(19+1)溶液定容,溶液经滤膜过滤后,供液相色谱-串联质谱仪测定。采用0.1%甲酸(A)-乙腈(B)作为流动相进行梯度洗脱,C18色谱柱分离,采用电喷雾电离,正离子扫描,多离子检测模式对MQCA的定量离子和定性离子进行监测,基质匹配内标(MQCA-D4),标准曲线法定量。结果 喹乙醇残留标志物3-甲基喹噁啉-2-羧酸(MQCA)在0.5-100μg/L浓度范围内线性良好,相关系数r²大于0.99;该方法的检出限和定量限分别为0.3μg/kg和 0.5μg/kg;3-甲基喹噁啉-2-羧酸在1.0、5.0、20μg/kg添加水平的回收率为93.9%-101.3%,相对标准偏差小于5.8%。结论 该方法简单快速,准确,灵敏,适用于猪肝中喹乙醇残留标志物3-甲基喹噁啉-2-羧酸的快速检测。     

高效液相色谱-串联质谱法同时测定鸡肉、 鸡蛋中喹乙醇和卡巴氧及代谢物残留

目的建立高效液相色谱-电喷雾电离串联质谱法测定鸡肉、鸡蛋中喹乙醇、卡巴氧及其代谢物残留量的分析方法。方法组织样品中的卡巴氧和喹乙醇用乙腈-乙酸乙酯(1:1, V:V)溶液提取;代谢物的提取用蛋白酶酶解后经盐酸溶液酸化,采用阴离子交换固相萃取柱净化和富集。分析样品以0.1%甲酸溶液-甲醇进行梯度洗脱,经Waters Xbridge C_(18)色谱柱分离,以液相色谱串联质谱多反应监测(multiple reaction monitoring,MRM)正离子模式进行检测。结果 5种喹喔啉类药物在0.5～50ng/mL浓度范围内线性良好,相关系数r~2为0.9956～0.9988;该方法的检出限和定量限分别为0.1～0.5μg/kg和1.0～2.0μg/kg;鸡蛋和鸡肉样品中,喹乙醇、卡巴氧、脱氧卡巴氧、喹喔啉-2-羧酸和3-甲基喹喔啉-2-羧酸在0.2～2.0μg/kg加标水平的平均回收率为85.1%～108.2%,日内精密度为4.9%～8.7%,日间精密度为6.2%～11.7%。结论该方法简单有效、回收率好、灵敏度高、特异性好,能满足日常检测的需求。     

高效液相色谱-串联质谱法测定动物源食品中喹乙醇代谢物残留量

建立动物源性食品中喹乙醇代谢残留标识物3-甲基喹喔啉-2-羧酸残留量的高效液相色谱串联质谱法。样品均质后,经Protease蛋白酶进行过夜酶解,加入盐酸酸化,离心,过滤后采用阴离子交换固相萃取柱Oasis MAX进行净化和富集。分析样品经Kinetex C18色谱柱分离,在高效液相色谱-串联质谱多反应监测模式下进行定性、定量分析,采用正离子扫描。6种测定样品中3-甲基喹喔啉-2-羧酸定量下限均为0.5μg/kg,鳗鱼、虾、鸡肉、猪肉、牛肉和猪肝在0.5、1.0、4.0μg/kg和10.0μg/kg四个添加水平的平均回收率在60.7%～107%之间,相对标准偏差(n=10)在4.59%～14.9%之间。本方法分析速度快、灵敏度高、重现性好,各项技术指标均满足国内外相关法规要求,适用于动物源性食品中喹乙醇代谢物3-甲基喹喔啉-2-羧酸残留的确证检测。     

超高效液相色谱-串联质谱法检测罗非鱼中喹乙醇及其衍生物

目的建立超高液相色谱-串联质谱法(ultra high pressure liquid chromatography-mass spectrometry,UPLC-MS/MS)测定罗非鱼中喹乙醇(olaquindox,OLQ)及其代谢物3-甲基-喹噁啉-2-羧酸(3-methyl-quinoxaline-2-carboxylic acid,MQCA)含量的分析方法。方法样品经10mL 50%甲醇溶液50℃水浴超声提取,PPL固相萃取小柱净化,经2 mL去离子水淋洗、2 mL 60%甲醇溶液洗脱,以乙腈-0.1%甲酸为流动相,经syncronis C_(18)色谱柱分离,采用多反应监测正离子模式进行定性及定量分析。结果 OLQ和MQCA在0.01～5.(μg/mL范围内线性关系良好,相关系数(r~2)均大于0.998,检出限为0.003 mg/kg和0.001 mg/kg,定量限为0.01 mg/kg和0.003 mg/kg,OLQ的3个水平加标回收率为87.0%～98.0%,RSD为3.3%～4.7%;MQCA的3个水平加标回收率为79.0%～84.0%,RSD为1.4%～3.6%。结论该方法具有灵敏度高、重复性好、准确度高、样品前处理操作简便和检测速度快的优点,适用于罗非鱼中喹乙醇及其代谢物MQCA快速高效定量、定性分析。     

超高效液相色谱串联质谱法测定鸡蛋中喹乙醇及卡巴氧代谢物

目的建立超高效液相色谱串联质谱法检测鸡蛋中喹乙醇代谢物3-甲基-喹恶啉-2-羧酸以及卡巴氧代谢物喹恶啉-2-羧酸的分析方法。方法样品经酶解后,用乙酸乙酯提取,PAX固相萃取柱净化,用色谱柱WATERS ACQUITY UPLC HSS T_3(2.1 mm×100 mm, 1.8μm)分离,同位素内标法定量。结果 3-甲基-喹恶啉-2-羧酸及喹恶啉-2-羧酸的最低检出限均为0.2μg/kg,定量限均为0.6μg/kg,平均回收率为80.9%～106.4%,相对标准偏差为2.6%～7.2%。结论该方法净化效果好,灵敏度高,准确性好,适用于鸡蛋中喹乙醇以及卡巴氧代谢物的同时检测。     

液相色谱-串联质谱法测定水产品中喹乙醇和卡巴氧的代谢物残留量

目的建立液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)测定水产品中喹乙醇代谢物3-甲基-喹噁啉-2-羧酸(3-methyl-quinoxaline-2-carboxylic acid,MQCA)和卡巴氧代谢物喹噁啉-2-羧酸(quinoxaline-carboxylic acid,QCA)的残留量的分析方法。方法样品在0.2 mol/L Tris/HCL缓冲溶液作用下,47℃水浴振荡进行酶解,将与组织以结合态形式存在的MQCA和QCA转变为游离态,酶解液经盐酸酸化,乙酸乙酯提取,提取液吹干后加入20%甲醇水溶解,过PAX固相萃取柱净化,浓缩定容,采用ACQUITY UPLC HSS T_3色谱柱分离,以乙腈、0.1%甲酸溶液为流动相,多反应离子监测(multiplereaction reaction monitoring,MRM)模式测定,内标法定量。结果 MQCA和QCA在2.5~100 ng/m L范围内呈良好的线性关系,相关系数(r~2)均大于0.99。在0.5、2.5和10μg/kg加标水平下(n=6),MQCA和QCA的平均回收率为75.6%~92.4%,相对标准偏差为3.81%~9.73%。MQCA和QCA的检出限均为0.25μg/kg,定量限均为0.5μg/kg。结论该方法灵敏、准确,重复性好,适用于水产品中MQCA和QCA残留量的同时测定。     

超高效液相色谱-串联质谱法测定畜肉中喹乙醇和代谢物残留及其冷冻储藏稳定性研究

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）测定畜肉中喹乙醇(Olaquindox, Ola)及其代谢物3-甲基-喹噁啉-2-羧酸（3-methyl-quinoxaline-2-carboxylic acid, MQCA）残留量检测方法，并研究在冷冻储藏条件下畜肉中Ola及MQCA的稳定性。方法 采用碱性水解提取畜肉中Ola及MQCA，经混合型阴离子交换固相萃取柱净化，以乙腈和0.2%甲酸溶液为流动相，经C18色谱柱洗脱分离，电喷雾正离子模式电离，多反应监测（multiple reaction monitoring，MRM）模式检测，外标法定量；通过降解率，分析畜肉中Ola和MQCA在冷冻储藏条件下的稳定性。结果 Ola及MQCA在0.5～100.0 μg/kg范围内，质谱响应强度与其质量浓度呈良好的线性关系，相关系数（r）≥0.9996；检出限均为0.1 μg/kg，定量限均为0.3 μg/kg；加标回收率为93.4%～98.6%，相对标准偏差为1.2%～3.7%；Ola及MQCA在-20 ℃储藏180 d是稳定的。结论 该法样品前处理操作简单、准确度高、精度好，可为畜牧养殖和畜肉质量安全监控提供检测方法。     

3-甲基-喹噁啉-2-羧酸半抗原的定向合成与鉴定

为实现定向合成3-甲基-喹噁啉-2-羧酸半抗原,针对3-甲基-喹噁啉-2-羧酸与4-氨基丁酸反应合成3-甲基-喹噁啉-2-羧酸半抗原进行全面研究。通过单因素试验和正交试验对试验条件进行优化,结果表明:氯甲酸异丁酯和4-氨基丁酸的添加量对半抗原的定向合成至关重要,当两者的添加量不当时就会生成副产物,甚至导致目标半抗原得率为0%;此外,确定了半抗原最佳合成条件:氯甲酸异丁酯120μL、3-甲基-喹噁啉-2-羧酸与4-氨基丁酸的物质的量比1∶2.5、活化时间1 h、反应时间1 h,在此条件下,得率高达76.92%。经纯化半抗原纯度99%(高效液相色谱检测)。本研究实现了3-甲基-喹噁啉-2-羧酸半抗原的定向合成,为抗体制备和相关快速检测产品开发提供了坚实的基础。     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

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 Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.     

National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the "13~(th) Five-Year Plan"

In Apri Commi major p Plan＂ （h 2014, the National Development and Reform ssion issued an announcement for selection of reliminary research projects for the ＂13th Five-Year ereafter referred to as ＂The Announcement＂）     

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 latest scientific     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

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.