两种方法测定对乙酰氨基酚注射液中盐酸半胱氨酸含量的比较研究

目的比较紫外-可见分光光度法和柱前衍生高效液相色谱法(HPLC)两种方法测定对乙酰氨基酚注射液中抗氧剂盐酸半胱氨酸的含量差异,研究盐酸半胱氨酸含量测定方法的可靠性。方法紫外-可见分光光度法:通过盐酸半胱氨酸与酸性茚三酮溶液反应生成红色产物,在559 nm波长处测定吸收度;柱前衍生HPLC:以2,4-二硝基氟苯为衍生化试剂,与对乙酰氨基酚注射液在60℃水浴暗处反应,HPLC测定。采用Agilent extend C_(18)(250 mm×4.6 mm,5μm)色谱柱,以乙腈-0.014 mol/L磷酸氢二钾溶液(用磷酸溶液调pH 8.2)(35:65)为流动相,流速1.0 mL/min,检测波长360 nm。结果使用紫外-可见分光光度法,测得3批样品的含量分别为0.24,0.24,0.23 mg/mL。使用柱前衍生HPLC,测得3批样品的含量分别为0.23,0.24,0.23 mg/mL。结论紫外-可见分光光度法和柱前衍生HPLC均可准确测定对乙酰氨基酚注射液中的抗氧剂盐酸半胱氨酸的含量。     

白藜芦醇苷的稳定性研究

通过紫外分光光度法,研究了温度、光照、pH、氧化剂对白藜芦醇苷稳定性的影响。结果表明:白藜芦醇苷对热、紫外光,尤其是直射太阳光的稳定性较差;而对pH表现较为稳定;白藜芦醇苷稳定性受氧化剂影响较大,白藜芦醇苷在常温、弱酸性或中性、避光条件下提取分离及储存较适宜。     

发酵液中红霉素的含量测定

建立了红霉素的含量测定方法-初筛用紫外分光光度法(UV),复筛用高效液相色谱法(HPLC).UV法确定磷酸浓度10mol/L,反应温度80℃,反应时间3min,测定波长485nm;确定HPLC法柱温50℃,检测波长210nm.此种方法针对性好,适用于大批量的红霉素发酵液的检测.     

非洲山毛豆种子中鱼藤酮类化合物的含量测定

分别采用高效液相法和紫外分光光度法测定山毛豆种子中鱼藤酮及其类似物的含量.两种试验方法均以鱼藤酮为对照品.用紫外分光光度法在其最大吸收波长294 nm处进行测定.高效液相色谱法以zorbax eclipse plus C18 (4.6 mm×250 mm,5 μm)为色谱柱,流动相为V(甲醇)∶V(水)=69∶31,柱温25℃,流速0.8 mL/min,进样量10μL,检测波长294 nm.试验结果表明,紫外分光光度法测定鱼藤酮类物质含量为24.29 mg/g,高效液相色谱法测定鱼藤酮含量为1.49 mg/g.方法学考察显示,UV法具有方法简便、快速、准确、经济等特点,是一种检测非洲山毛豆种子鱼藤酮类物质含量的较好手段.HPLC法操作相对复杂,但专属性强,重现性好,回收率高,是一种测定鱼藤酮有效含量的方法.     

高效液相法测定杨梅苷脂质体的药物含量及包封率

本文建立了杨梅苷脂质体中药物含量及包封率测定的高效液相新方法.该方法使用C18色谱柱(150mm×4.6mm,5μm);流动相为甲醇-磷酸盐缓冲溶液(40:60);流速为0.4 mL/min;柱温为室温;紫外检测波长为367nm.采用冷冻离心法分离杨梅昔脂质体中的游离药物.结果表明在本色谱条件下杨梅苷与卵磷脂、溶剂峰能有效分离,杨梅苷在0.8～40 μg/mL(r=0.9999,n=5)具有良好的线性关系,回收率100.9%～101.9%,日内RSD及日间RSD均<2%(n=5).该方法准确可靠、简单易行,可以用于杨梅苷脂质体含量及包封率的测定.     

维生素C注射液含量测定的几种方法比较

维生素C注射液含量测定的几种方法比较。碘量法测定条件:醋酸酸性条件,丙酮,淀粉指示剂,碘滴定液;紫外分光光度法条件:波长245 nm,溶剂0.01mol/L盐酸溶液;高效液相色谱法测定条件:C18柱,流动相0.01mol/L磷酸二氢钠溶液(PH为2.5),流速0.6ml/min,检测波长245nm。     

甘油铜分光光度法和HPLC测定生物柴油转化率的比较研究

采用分光光度法测定生物柴油制备过程中副产物甘油的含量,确立了最佳的实验条件:在甘油溶液中依次加入KOH溶液和CuSO4溶液,超声5 min,过滤,于629 nm波长处测其吸光度.运用HPLC对分光光度法的准确度进行验证,结果表明分光光度法可以精确地检测酯交换反应的进度.     

HPLC测定特殊医学用途电解质配方食品中罗汉果甜苷V含量

目的 建立测定特殊医学用途电解质配方食品中罗汉果甜苷V含量的高效液相色谱法(HPLC).方法 采用HPLC,Hypersil C18(250 mm×4.6 mm,5μm)色谱柱,流动相为0.1％磷酸溶液:乙腈=76:24,流速1.0 ml/min,检测波长203 nm.结果 罗汉果甜苷V在0.05～1.0μg质量范围内...     

青海蚕豆中原花青素和左旋多巴的含量测定和品种间差异的比较

目的:建立青海蚕豆中左旋多巴和原花青素含量测定方法,测量22批样品的含量。方法:采用紫外分光光度法测量原花青素的含量,检测波长为554nm。采用HPLC法检测蚕豆中L-多巴含量:色谱柱:汉邦ODS-2(250mm×4.6mm,5μm),流动相:甲醇-0.1mol/L冰醋酸溶液(5∶95);流速:0.8 mL/min;测定波长:280 nm;柱温:25/3℃;进样量:20μL。结果:原花青素在75~375μg/mL范围内线性良好、L-多巴在75~375μg/mL范围内线性良好。结论:青海蚕豆中左旋多巴和原花青素含量测定方法稳定可靠。     

分光光度法测定水力空化对绿原酸的影响

为探明水力空化对绿原酸的影响,通过空化装置产生空化效应并作用于绿原酸溶液。研究了不同入口压力、温度、作用时间等条件下水力空化对绿原酸的影响。以分光光度法监测水力空化处理绿原酸溶液中其含量及色度,采用紫外分光光度法在吸收波长为324 nm时对溶液中绿原酸定量分析,同时采用可见分光光度法在吸收波长为560 nm时对绿原酸溶液进行色度测定。结果发现,水力空化对绿原酸的影响明显,随着压力增大、温度升高或作用时间延长,溶液中绿原酸的含量减小且溶液色泽加深。这为绿原酸在食品和药品等行业中的应用做出了贡献,也为水力空化在制糖工艺、废水处理等工业化中的应用提供了重要的参考。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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