HPLC测定盐酸左氧氟沙星滴眼液中防腐剂羟苯乙酯含量

目的 建立HPLC测定盐酸左氧氟沙星滴眼液中防腐剂羟苯乙酯含量的方法.方法 以十八烷硅烷基键合硅胶为填充剂;以0.005 mol/L醋酸铵溶液(每1 000 mL含三乙胺10 mL,用冰醋酸调pH 5.0)-乙腈(50∶50)为流动相;检测波长256 nm;流速1.0 mL/min;柱温35℃.结果 羟苯乙酯在0.017 7～0.041 3 mg/mL范围内呈良好的线性关系(r=0.999 97).平均回收率100.4%(n=9),RSD=0.97%.结论 此法简便、快速、准确,可有效控制产品质量.     

高效液相色谱法测定氯化钾口服液中羟苯乙酯的含量

目的建立高效液相色谱(high performance liquid chromatography,HPLC)测定氯化钾口服液中防腐剂羟苯乙酯含量的分析方法。方法采用Eclipse XDB-C_(18)柱(250 mm×4.6 mm,5μm),甲醇:水(80:20,V:V)为流动相,流速为1.0 mL/min,检测波长为254 nm,柱温为40℃。结果羟苯乙酯在20.16~403.20μg/mL范围内线性良好,标准曲线方程为Y=8.18×10~4X+88.2(r=0.9992),平均加样回收率为99.22%,相对标准偏差(relative standard deviation,RSD)为1.0%(n=6)。结论该方法简便,准确可靠,灵敏度高,适合用于氯化钾口服液中羟苯乙酯含量测定。     

RP-HPLC测定替比培南酯中聚合物含量

目的建立RP-HPLC测定替比培南酯中聚合物含量的方法。方法采用十八烷基硅烷键合硅胶为填充剂（Waters XBridge C18,5μm,4.6 mm×250 mm）,柱温为40℃;以0.025 mol/L磷酸二氢钠溶液（用1 mol/L氢氧化钠溶液调pH为6.0）-乙腈（50：50）为流动相,流速1.0 mL/min;检测波长220 nm,进样量10μL。结果替比培南酯对照液浓度在5.84～13.63μg/mL范围内具有良好的线性关系（r=0.9992）;对照溶液在24 h内稳定;对照溶液精密度RSD为0.45%;定量限为0.58μg/mL;最低检出限为0.17μg/mL;重复性试验显示本方法重复性良好。结论此法灵敏度高,操作简便,准确可靠,可用于替比培南酯中聚合物含量的测定。     

HPLC法测定糕点类食品中的8种常用防腐剂

建立HPLC法测定糕点类食品中的苯甲酸、山梨酸、脱氢乙酸、纳他霉素、羟苯甲酯、羟苯乙酯、羟苯丙酯和羟苯丁酯。采用Waters Sunfire C_(18)色谱柱,采用梯度洗脱,UV-VIS检测器检测,外标法定量分析。结果表明,8种常用防腐剂质量浓度在0.2~5μg/m L范围内线性关系良好,相关系数r2均大于0.999;检出限为0.05~0.13 mg/kg;样品加标回收率为90.6%~100.8%;精密度结果的相对偏差为0.46%~2.62%(n=6);重复性结果的相对偏差为1.22%~3.06%(n=6)。试验证明该方法具有操作简单、准确度高、灵敏度高等优点。     

RP-HPLC法检测饮料中常见的8种防腐剂和2种甜味剂

建立一种利用反向高效液相色谱法检测饮料中常见的8种防腐剂和2种甜味剂的方法。以甲醇-乙酸铵体系为流动相,用Waters xbrige RP-C18色谱柱进行梯度洗脱分离,UV-VIS检测器检测,外标法定量测定。结果表明,各组分分离度符合要求;10种添加剂的质量浓度在0.5~50μg/m L时,线性关系良好,相关系数均大于0.999,其检出限分别为:安赛蜜0.08μg/g、苯甲酸0.09μg/g、山梨酸0.05μg/g、糖精钠0.15μg/g、脱氢乙酸0.18μg/g、纳他霉素0.10μg/g、羟苯甲酯0.07μg/g、羟苯乙酯0.07μg/g、羟苯丙酯0.07μg/g、羟苯丁酯0.07μg/g,样品加标回收率均在90.0%~105.0%之间,精密度(n=6)在5.0%以内;重复性(n=6)在5.0%以内。试验证明该方法具有前处理简单、检测限低、检测结果准确等优点。     

气相色谱法测定食品中对羟基苯甲酸酯

目的 建立食品中对羟基苯甲酸酯的气相色谱分析方法。方法 样品用正己烷和乙醚萃取, 浓缩后, 最后用毛细管柱气相色谱法测定。结果 2 种对羟基苯甲酸酯在 10~1000 μg/mL 范围内呈良好的线性关系, 相 关系数均大于 0.999, 方法检出限为 0.01 mg/kg (S/N=3), 在 10、50、100 μg/mL 三个添加水平下, 样品中对羟 基苯甲酸酯的平均回收率在 85.8%~115.3%之间, RSD<10% (n=6)。结论 本方法, 灵敏度高, 重现性好, 简单 快捷, 能满足常规检测及食品安全控制的需要。     

HPLC检测大鼠组织样品中花椒麻素方法的建立

目的：建立高效液相色谱法测定大鼠组织样品中花椒麻素含量的方法。方法：采用Intersil ODSSP C18（250 mm×4.6 mm,5 μm）为分析柱,流动相甲醇-水（70∶30,V/V）,流速0.5 mL/min,检测波长 254 nm。结果：心、肝、脾、肺、肾脏、脑、胃、小肠、脂肪、肌肉、皮肤、睾丸及前列腺的线性范围分别为 0.1～10 μg/mL（r=0.998 6）、0.1～50 μg/mL（r=0.999 9）、0.1～10 μg/mL（r=0.999 7）、0.1～10 μg/mL （r=0.998 9）、0.1～20 μg/mL（r=0.999 3）、0.1～10 μg/mL（r=0.999 5）、0.1～100 μg/mL（r=0.999 9）、 0.1～50 μg/mL（r=0.998 2）、0.1～20 μg/mL（r=0.995 6）、0.1～10 μg/mL（r=0.998 8）、0.1～10 μg/mL （r=0.999 7）、0.1～10 μg/mL（r=0.999 8）及0.1～10 μg/mL（r=0.999 8）。方法平均回收率大于 82%,日内日间变异均小于11%,稳定性良好。结论：本方法准确、快速、重复性好,适用于大鼠组织样 品中花椒麻素含量的测定。     

核桃多肽-苦荞-藜麦复合粉制备工艺及体外消化和抗氧化功能特性分析

以核桃多肽、苦荞、藜麦为原料,按不同比例复配,根据氨基酸比值系数分计算方法评价3?种原料蛋白营养价值得出最佳复配比例,通过单因素及正交试验确定了苦荞、藜麦复配后最佳液化、糖化条件,再与核桃多肽按最佳复配比例混匀,经喷雾干燥得到核桃多肽-苦荞-藜麦复合营养粉,在此基础上,对复合粉进行体外消化和抗氧化功能的研究。结果表明：核桃多肽-苦荞-藜麦最佳复配比为0.7∶13∶5（质量比）,此时氨基酸比值系数分值为95.15%,接近参考蛋白模式;最佳液化条件为α-淀粉酶添加量7?U/g、温度60?℃、时间50?min,最佳糖化条件为β-淀粉酶添加量150?U/g、温度55?℃、时间2.5?h,此时还原糖质量浓度为20.03?mg/mL;体外模拟消化过程中多肽、还原糖、黄酮和多酚含量均随时间延长而升高,尤其小肠模拟消化过程中快消化淀粉质量分数高达64.19%,慢消化淀粉质量分数高达27.12%,抗性淀粉质量分数仅为8.70%,说明淀粉经过胃肠消化后水解更彻底;复合粉经实验证明表现出一定的抗氧化能力,分别为还原力（IC50=5.04?mg/mL）、DPPH自由基清除能力（IC50=0.67?mg/mL）、羟自由基清除能力（IC50=62.32?mg/mL）、O2－·清除能力（IC50=13.07?mg/mL）和总抗氧化能力（27.63?U/mL）。通过实验研制出一种富含核桃多肽、苦荞、藜麦的复合营养粉,易于消化吸收且具有一定的抗氧化活性。     

迷迭香酸在沙棘果酒中的应用研究

以沙棘果浆为原料,以不添加抗氧化剂、添加抗氧化剂迷迭香酸或二氧化硫进行果酒发酵。在发酵过程中和发酵结束后,通过DPPH法、水杨酸法和普鲁士蓝法测定果酒的抗氧化性。结果表明,添加迷迭香酸作为抗氧化剂替代二氧化硫,果酒的理化指标均在国标允许范围内,不会影响果酒发酵。3种方式发酵果酒清除DPPH·的能力大小顺序为迷迭香酸果酒（IC50=8.02 mg/mL）＞二氧化硫果酒（IC50=10.31 mg/mL）＞无添加抗氧化剂果酒（IC50=11.47 mg/mL）;清除·OH的能力大小顺序为迷迭香酸果酒（清除率99.31%）＞无添加抗氧化剂果酒（清除率98.83%）＞二氧化硫果酒（清除率98.67%）;还原力大小顺序为二氧化硫果酒＞迷迭香酸果酒＞无添加抗氧化剂果酒。     

不同酵母对威士忌品质的影响

以大麦芽为原料,选用3种不同酵母（ACBC-1、ACBC-2及ACBC-3）发酵制备威士忌。比较不同酵母的发酵性能、理化指标及出酒率,采用气相色谱（GC）法测定威士忌挥发性香气物质,通过气味活度值（OAV）确定关键香气化合物并进行主成分分析（PCA）,并对制备的酒样进行感官评价。结果表明,酵母ACBC-1发酵性能最好,其发酵液的理化指标良好（总酸3.73 g/L,残糖3.00 g/100 g,酒精度6.42%vol,pH 4.1）,出酒率最高（70.78 mL/kg）。3个酒样共检出24种风味物质,其中醇类化合物为主,占77%～98%;OAV＞1的酯类化合物种类最多（5种）,其中乙酸苯乙酯、乙酸异戊酯及乙酸苯乙酯是关键香气物质,对酒样的香气贡献最大。3种酵母制备威士忌酒样感官评分顺序ACBC-1（90分）＞ACBC-2（76分）＞ACBC-3（71分）。结果表明,酵母ACBC-1适合酿造威士忌。     

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