芦丁分子印迹聚合物的制备及其吸附性能的研究

以芦丁为模板分子,以α-甲基丙烯酸(MAA)和丙烯酰胺(AM)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,利用分子印迹技术在甲醇/水(V/V,1/4)溶剂中合成了芦丁分子印迹聚合物(MIPs),研究了不同功能单体及其用量和不同交联剂用量的聚合体系组成对印迹聚合物吸附特性的影响。对最佳比例制备的MIPs进行了吸附等温实验和Scatchard分析,其结合位点的离解常数Kd分别为105.26mg.L-1和1250mg.L-1,饱和吸附量Qmax分别为18.02mg.g-1和73.50mg.g-1。并利用红外光谱(IR)对分子印迹聚合物进行了表征。     

吡蚜酮分子印迹聚合物的制备及吸附性能表征

以吡蚜酮为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,采用本体聚合法制备了吡蚜酮分子印迹聚合物。实验优化了模板分子与功能单体的摩尔比,通过吸附动力学和等温吸附实验对聚合物的吸附性能进行了表征,利用拟二级动力学模型和Scatchard分析研究了聚合物对目标物的吸附行为。实验结果表明:模板分子与功能单体摩尔比为1∶4时,制备的吡蚜酮分子印迹聚合物具有较好的印迹效果,最优条件下聚合物的吸附容量为25.11mg/g,印迹因子为3.0,可在80min内达到吸附平衡(20mg/L);聚合物对目标物的吸附行为符合拟二级动力学模型(R2=0.999),Scatchard分析结果表明聚合物在聚合过程中形成了较为明显的印迹位点,对目标物呈现一致的亲和力。     

氨基甲酸乙酯分子印迹聚合物的制备表征及分子识别性能研究

采用分子印迹技术,以β-环糊精衍生物为功能单体,氨基甲酸乙酯(EC)为模板分子,合成了对氨基甲酸乙酯有特异性识别和吸附的新型分子印迹聚合物(MIP)。通过红外光谱(IR)、核磁共振(13C-NMR)、扫描电镜(SEM)对其结构进行表征,利用气-质联用仪(GC-MS)测定该分子印迹聚合物对EC的选择性识别性能,构建Scatchard模型理论方程。结果表明,设计的反应合成路线合理,成功制备出新型EC分子印迹聚合物。合成的氨基甲酸乙酯分子印迹聚合物,通过共价键联分子作用对EC产生分子识别作用,表现出优异的选择性吸附功效。构建的理论方程定量解析出该分子印迹聚合物对模板分子有两类识别位点,动态理论方程体现出其优异的吸附特性。有关结果可为无特异性结构的氨基甲酸酯类污染物的去除和分离提供技术参考。     

香草醛分子印迹聚合物微球的合成及表征

香草醛作为食品中一种重要的调味剂,可以从热带兰花香荚兰的种子中找到。本文以香草醛(VAN)为模板分子,a-甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,二甲基亚砜(DMSO)为溶剂,分别采用沉淀聚合法、悬浮聚合法、本体聚合法制备了香草醛分子印迹聚合物(微球)(MIPs)。通过紫外光谱(UV)、傅里叶变换红外光谱仪(FT-IR)研究了模板分子与功能单体之间的相互作用和最佳配比,利用透射电子显微镜考察了分子印迹聚合物的微观形貌。采用平衡和等温吸附实验对印迹聚合物的吸附性能进行了研究。实验表明,MAA与VAN之间通过氢键相互作用,沉淀聚合法制备的MIPs具有均匀规则的球状结构,且表现出对VAN更好的结合能力,具有较高的特异识别性。     

植酸分子印迹聚合物的制备、表征及吸附性能

以植酸为模板分子,甲基丙烯酸(MAA)为功能单体,N,N'-乙烯基丙烯酰胺(EBA)为交联剂,过硫酸铵为引发剂,采用本体聚合法制备对植酸具有高特异选择性的植酸分子印迹聚合物(MIPs)。通过扫描电镜观察了分子印迹聚合物表面的结构,利用红外光谱进一步对其化学结构进行表征。通过动态吸附、静态吸附和选择性吸附考察了其吸附性能。研究表明植酸分子印迹聚合物对植酸的吸附高于对肌醇的吸附,植酸在印迹聚合物中的印迹因子为1.70,而与植酸结构相似物肌醇的印迹因子为1.46。解吸80 min,MIPs解吸达到稳定,解吸率达到89.59%。植酸分子印迹聚合物对植酸的吸附特异性强,对植酸的吸附量为21.38μmol·g~(-1),解吸效果好,进行吸附-解吸附循环5次后,植酸印迹聚合物的性能稳定,对植酸吸附容量为65.62μmol·g~(-1),是第一次吸附容量的90.00%,可重复使用。     

表面印迹法制备链霉素分子印迹聚合物及其性能研究

利用硅胶颗粒为基质,在其表面接枝硅烷化试剂3-甲基丙烯酰氧基丙基三甲氧基硅烷(γ-MPS),进行硅烷化处理后,以链霉素为模板分子,甲基丙烯酸(MAA)为功能单体,N,N’-亚甲基双丙烯酰胺(MBA)为交联剂在颗粒表面合成分子印迹层,制备得到链霉素分子印迹聚合物(MIPMs)和空白聚合物(NMIPMs),并采用静态平衡结合法借助高效液相色谱-蒸发光散射(HPLC-ELSD)研究了聚合物对模板分子链霉素的吸附能力、结合动力学和选择特性。扫描电镜观察和红外光谱分析结果表明表面印迹层已经成功合成;吸附实验结果表明,MIPMs比NMIPMs对链霉素具有更强的吸附特性和更好的选择性。     

双酚A环氧衍生物分子印迹聚合物的制备 及其吸附性能研究

目的 制备双酚A环氧衍生物的分子印迹聚合物。方法 采用沉淀聚合法, 以双酚A(bisphenol A, BPA)和双酚A二环氧甘油(bisphenol A diglycidyl ether, BADGE)为双模板分子, α-甲基丙烯酸(methacrylic acid, MAA)为功能单体, 三羟甲基丙烷三甲基丙烯酸酯(trimethylolpropane trim ethacrylate, TRIM)为交联剂, 偶氮二异丁腈(azodiisobutyronitrile, AIBN)为引发剂, 合成了一种高选择性的分子印迹聚合物, 运用扫描电镜、红外光谱分析等手段对其形貌、物理特征进行了表征, 同时进行了聚合物的静态吸附与动态吸附性能研究。结果 合成的分子印迹聚合物(molecularly imprinted polymers, MIPs)对10 种化合物的最大平衡吸附量为18.12~27.00 mg/g, 对10种化合物的吸附略有区别, 但差异不大, 而非印迹聚合物(non-imprinted polymers, NIPs)则对10种化合物的吸附量为7.10~10.73 mg/g, 说明NIPs吸附是由于存在物理吸附。结论 10种目标化合物在MIPs上均有吸附, 能够应用于分子印迹-固相萃取-高效液相色谱检测方法的建立。     

双酚A环氧衍生物分子印迹聚合物的制备及其吸附性能研究

目的制备双酚A环氧衍生物的分子印迹聚合物。方法采用沉淀聚合法,以双酚A(bisphenol A,BPA)和双酚A二环氧甘油(bisphenol A diglycidyl ether,BADGE)为双模板分子,α-甲基丙烯酸(methacrylic acid,MAA)为功能单体,三羟甲基丙烷三甲基丙烯酸酯(trimethylolpropane trim ethacrylate,TRIM)为交联剂,偶氮二异丁腈(azodiisobutyronitrile,AIBN)为引发剂,合成了一种高选择性的分子印迹聚合物,运用扫描电镜、红外光谱分析等手段对其形貌、物理特征进行了表征,同时进行了聚合物的静态吸附与动态吸附性能研究。结果合成的分子印迹聚合物(molecularly imprinted polymers,MIPs)对10种化合物的最大平衡吸附量为18.12~27.00mg/g,对10种化合物的吸附略有区别,但差异不大,而非印迹聚合物(non-imprinted polymers,NIPs)则对10种化合物的吸附量为7.10~10.73 mg/g,说明NIPs吸附是由于存在物理吸附。结论 10种目标化合物在MIPs上均有吸附,能够应用于分子印迹-固相萃取-高效液相色谱检测方法的建立。     

乙酸薄荷酯分子印迹聚合物的制备及其吸附特性

本文分别考察了不同单体、反应溶剂、充氮时间、反应温度、单体添加量、交联剂添加量对乙酸薄荷酯分子印迹聚合物制备的影响。结果表明,以乙酸薄荷酯为模板分子,丙烯酰胺为单体,以N,N-二甲基甲酰胺为反应溶剂制备的聚合物,其选择性比较好,通过聚合物的吸附分离,可以将薄荷素油中乙酸薄荷酯的含量提高到14.65%;而当单体、交联剂添加量与模板分子量的比例为1:4:16时,制备的聚合物对模板分子有较高的结合性能,结合量为5.09 mg/g,对乙酸薄荷酯和薄荷醇的分离因子为1.46,说明印迹聚合物对乙酸薄荷酯具有良好的吸附选择性。     

肉制品中磺胺类药物的分子印迹聚合物的模拟研究

以磺胺类药物(SFAs)为模板分子,甲基丙烯酸(MAA)为功能单体,模拟研究磺胺类药物的分子印迹聚合物。通过密度泛函理论的计算,分析反应介质对印迹聚合物制备过程的影响,并从分子水平上研究SFAs-MAA之间的结合作用,为制备合理的印迹聚合物提供参考。     

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.     

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     

Chinese CTP Market

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%.     

Preparatory Work of Print China 2015 is Going Smoothly

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