超高效液相色谱-串联质谱法测定奶酪中喹乙醇及其代谢物

目的建立超高效液相色谱-串联质谱法测定奶酪中喹乙醇及其代谢物3-甲基-喹噁啉-2-羧酸(3-methyl-quinoxaline-2-carboxylic acid,MQCA)的含量。方法样品经盐酸水解,乙酸乙酯-乙腈提取、富集,以乙腈-0.05%氨水为流动相,经Inertsil ODS-3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。结果喹乙醇和3-甲基-喹噁啉-2-羧酸的检出限分别为0.05μg/kg和0.02μg/kg,3个水平加标回收率为70.0%~109.0%,相对标准偏差分别为10.55%和4.73%。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,适用于奶酪中喹乙醇及其代谢物残留的检测。     

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。     

高效液相色谱-串联质谱法检测猪肉中喹乙醇代谢物

本文建立了猪肉中喹乙醇代谢物3-甲基-喹恶啉-2-羧酸(MQCA)的高效液相色谱-串联四极杆质谱(UPLCMS/MS)的分析方法。样品经过2%偏磷酸:甲醇(4:1)初步提取,乙酸乙酯再次提取,通过正己烷除油,旋转蒸发浓缩至干,乙腈-0.1%甲酸水复溶解,经过C18色谱柱分离,多重反应监测(MRM),内标法定量。结果表明:本方法MQCA检出限为0.1μg/kg,在0.5～10.0μg/kg范围内线性关系良好,r~2=0.999,平均回收率在71%～90%,相对标准偏差为0.9%～2.5%。结论:本方法适用于猪肉中喹乙醇代谢物残留的检测。     

硫胺素对鲁氏接合酵母高盐适应性的影响

采用同位素内标-超高效液相色谱串联三重四极杆质谱（UPLC-MS/MS）法测定金沙江攀枝花江段6种常见鱼中卡巴氧代谢物喹恶啉-2-羧酸（QCA）和喹乙醇代谢物3-甲基-喹恶啉-2-羧酸（MQCA）的残留量。样品经过预处理，采用ZORBAX SB-C18色谱柱分离，以0.1%甲酸水-乙腈为流动相进行梯度洗脱；采用电喷雾-正离子多反应监测模式（MRM）检测，同位素内标法定量。结果表明，QCA和MQCA的质量浓度为2.0～100.0 ng/mL时，线性关系良好（R＞0.999），回收率为91.4%～100.4%，精密度试验结果相对标准偏差（RSD）为6.3%～11.5%，定量限为0.2 μg/kg，检出限为0.05 μg/kg。该方法灵敏度及准确度良好，能满足6种常见鱼的组织中卡巴氧及喹乙醇代谢物残留分析的要求。     

碱水解-SPE-HPLC-MS/MS法检测乳制品中喹乙醇及代谢物

建立一种快速、高效的SPE-HPLC-MS/MS测定乳制品中的喹乙醇及代谢物的方法。样品前处理采用碱水解提取喹乙醇和MQCA,经MAX小柱净化后检测。以乙腈-0.1%氨水为流动相,在质谱检测器的多反应监测模式下进行分析。结果表明,喹乙醇和MQCA在0.1～50.0 ng/mL质量浓度范围内线性良好,相关系数R2为0.9992～0.9997,检出限均为5.0μg/kg,定量限均为20μg/kg。加标试验分别添加40,100和200μg/kg 3个浓度,加标回收率达到81.6%～97.1%(n=5)。该方法具有前处理简单、净化效果好、灵敏度高和检测速度快的优点,适用于乳制品中的喹乙醇及代谢物残留量的检测和确证。     

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-串联质谱法测定乳饼中的氯霉素

目的建立一种超高效液相色谱-串联质谱法(ultra high performance liquid chromatography tandem mass spectrometry, UPLC-MS/MS)检测乳饼中氯霉素的分析方法。方法样品经乙酸乙酯提取,分析了分别经C18(100 mm×2.1 mm, 1.7μm)及MCS固相萃取柱净化、富集的结果;以乙腈-0.05%氨水为流动相,经C18色谱柱分离,采用多反应检测负离子模式进行定性及定量分析。结果 MSC固相萃取柱具有较好的回收率,氯霉素的方法检出限为0.004μg/kg,方法定量限为0.01μg/kg,在0.10、0.50、1.00、10.00 ng 4个加标水平下回收率分别为76.4%、101%、62.4%、61.1%。结论本方法灵敏度高、重复性好,可满足乳饼样品中痕量氯霉素残留的测定。     

高效液相色谱-串联质谱法测定肌肉组织中4种兽药残留

建立同时测定肌肉组织中新霉素、灰黄霉素、多黏菌素B、喹乙醇及其代谢物3-甲基喹啉-2-羧酸(3-methyl-quinoxaline-2-carboxylic acid,MQCA)的高效液相色谱-串联质谱(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)分析方法。肌肉组织匀浆均质后使用乙腈-5%甲酸水溶液提取,HLB固相色谱柱净化,HPLC分离,电喷雾离子源正离子模式及多反应监测模式检测,外标法定量。结果表明:4种兽药在质量浓度1.0~200.0ég/L范围内均表现出良好的线性关系,R2均大于0.998 0;新霉素、灰黄霉素和多黏菌素B的方法检出限为5.0μg/kg,喹乙醇及MQCA为0.5μg/kg;阴性样品中4种兽药的加标回收率为82.1%~98.4%,日内相对标准偏差(relative standard deviation,RSD)(n=6)为2.2%~6.7%。该方法前处理过程简单、干扰较少,检测结果准确,适用于肌肉组织中4种兽药的定性与定量检测。     

固相萃取小柱-超高效液相串联质谱测定牛奶中氯霉素

建立可靠的前处理方法,采用超高效液相色谱-串联质谱法检测牛奶中氯霉素。样品经乙酸乙酯提取,分析了分别经C18及MCS固相萃取柱净化、富集的结果;以乙腈-0.05%氨水为流动相,经C18色谱柱分离,采用多反应检测负离子模式进行定性及定量分析。结果表明,MSC固相萃取柱具有较好的回收率,氯霉素的方法检出限为0.004μg/kg,方法定量限为0.01μg/kg,在0.01、0.25、1.00μg/kg 3个加标水平下回收率分别为71.0%、53.8%、50.4%。本法灵敏度高、重复性好,可满足牛奶样品中痕量氯霉素残留的测定。     

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。     

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.     

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.     

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     

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,     

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