基于离子液体微乳液淀粉纳米微球载药性和释药性研究

该文以可溶性淀粉为原料,以溴化1–十六烷基–3–甲基咪唑(C16mim Br)和正丁醇为表面活性剂,采用W/O微乳液交联法制备淀粉纳米微球。然后以淀粉纳米微球为载体,广谱性抗肿瘤药物盐酸米托蒽醌为模型药物,采用物理吸附法,以载药量和包封率为评价指标,对载药时间、载药温度和药物浓度进行优化筛选,并且对载药淀粉纳米微球的体外释药性能进行评价。实验表明:载药温度、载药时间和药物浓度对淀粉纳米微球的载药量和包封率有极大的影响,在载药时间为2 h、载药温度为27℃、盐酸米托蒽醌浓度为0.08 mg/m L时,包封率达到最大值,为23.7%。当释药时间达到10 h时,淀粉纳米微球的体外累积释药率达85.53%,因此其具有良好的释药性能。     

微孔淀粉对2,4-二硝基苯酚的负载与缓释

为降低2,4-二硝基苯酚(DNP)的毒副作用,延长药效时间,本文以α-淀粉酶催化水解玉米淀粉制备的微孔淀粉作为载体,负载DNP制成缓释制剂,并考察了其体外释放性能。结果表明:微孔淀粉对DNP的吸附平衡时间为1 h,增加DNP的初始浓度及降低负载过程温度有利于增加吸附量。在DNP初始浓度为500 mg/L、吸附温度为25℃、吸附时间为1 h时,微孔淀粉对DNP吸附量可达3.4369 mg/g。动力学及热力学模型拟合结果表明,微孔淀粉对DNP的吸附是范德华力和氢键共同作用的表面物理吸附,为可自发进行的放热过程。在模拟胃液和模拟肠液释放介质的体外释放实验中,0.50 g的DNP-微孔淀粉缓释制剂(载药量为3.3085 mg/g)的释放时间可达12 h,释药量分别为91.18%和89.29%;而原料药在模拟胃液和模拟肠液中完全释放时间分别为4、3 h,DNP累积释放量分别为91.01%、92.23%。DNP-微孔淀粉缓释剂的释放动力学分析表明,DNP-微孔淀粉在模拟胃液中为扩散和溶蚀协同作用释药,符合Peppas动力学方程;在肠液中遵循Fickian的扩散符合一级动力学模型。因此,微孔淀粉对DNP具有良好的吸附和缓释性能,本研究可为DNP缓释制剂开发与应用提供基础。     

木薯淀粉水凝胶负载姜黄素及缓释性能研究

为提高木薯淀粉应用价值,以木薯淀粉为原料,丙烯酰胺为单体,过硫酸钾为引发剂,N,N-亚甲基双丙烯酰胺为交联剂制备具有良好机械性能、可用作药物载体的木薯淀粉水凝胶。通过傅里叶红外光谱、核磁共振、X-射线衍射等分析测试手段对其进行表征。成功制备木薯淀粉水凝胶,且机械性能良好。以制得的水凝胶为载体,探究了水凝胶负载姜黄素的载药性能及缓释性能。结果表明:载药性能良好,最佳载药条件为载药时间0. 5h,乙醇体积分数20%,温度35℃,药液初始浓度100μg/m L,载药量可达到100 mg/g。纯姜黄素与负载于水凝胶中的姜黄素作对照,纯姜黄素突释明显,水凝胶中姜黄素释放缓慢,72 h后累积释药率达到80%左右,表明水凝胶作为载体具有药物缓释的作用。     

淀粉纳米颗粒的醇沉法制备与同步包埋山奈酚的研究

以木薯淀粉为原料,通过超声波搅拌制备淀粉纳米颗粒,采用扫描电镜、激光纳米粒度仪、X-射线衍射进行表征。在淀粉纳米颗粒的沉降阶段中,以0.7 mg/mL的山奈酚醇溶液作为非溶剂相,同步对山奈酚包埋,制备山奈酚淀粉纳米颗粒。探索乙醇浓度对山奈酚包埋率的影响,考察包埋体系对山奈酚释放率和稳定性的影响。结果表明,乙醇浓度在60%时形成淀粉纳米颗粒,形貌较好,尺寸均匀分布在50～200 nm之间;乙醇浓度低于40%时生成V型淀粉颗粒。乙醇浓度为30%时,山奈酚的包埋率最高,可达62.94%,包埋量为3.78 mg/g;在模拟体液环境中,山奈酚淀粉纳米颗粒可持续释药20 h,释药率为88.75%,而山奈酚原药在3 h基本释放完全,释放率为93.75%,且释放速率随缓释介质的乙醇浓度升高而加快。相对山奈酚水溶液,山奈酚淀粉纳米颗粒在室温下静置5 h,山奈酚的保留率由43.17%提高至75%,具有稳定的包埋作用。由此可知,同步包埋制备技术对山奈酚具有良好的包埋缓释效果和稳定作用。     

淀粉纤维的成形及其载药控释研究进展

为制备孔隙率高、比表面积大、药物释放性能可控的载药淀粉纳米纤维,促进其在载药外敷等生物医学领域中的应用,从淀粉纤维的成形及其载药控释2个方面进行综述。首先,系统介绍了近年来国内外关于淀粉纤维的制备方法与工艺特点。针对淀粉纤维的成形机制,详细阐述了改性淀粉基纤维、共混淀粉基纤维、纯淀粉纤维的发展进程、性能特点及研究进展;针对载药淀粉纳米纤维在药物释放过程出现初始爆发释放的问题,介绍了交联改性等方法对淀粉纳米纤维膜载药控释性能的影响。最后,对淀粉纳米纤维在载药外敷领域所面临的困难和挑战提出了应对策略,并对其未来的研究方向进行展望。     

壳聚糖复合纳米载药体系的构建及其释药性能

为了提高化疗药物的安全性和有效性,以阳离子多糖壳聚糖为载体,抗癌药5-氟尿嘧啶和丹参素钠为药物模型,采用聚电解质复合法构建了新型控/缓释壳聚糖基复合纳米载药体系,考查了药物初始投加量、浓度、质量比对载药壳聚糖纳米颗粒粒径及其分布的影响。采用红外光谱仪、激光粒度仪、透射电镜对其结构、粒径及形貌进行表征,并研究了2种载药体系的体外药物释放行为以及壳聚糖载药体系的生物相容性。结果表明：对于载5-氟尿嘧啶体系,当质量浓度为0.8 g/L,质量比为5∶3时,粒径为382 nm;对于载丹参素钠体系,当质量比为10∶7时,粒径为425 nm。与游离药物相比,载药纳米颗粒控释效果更明显;初始投加量、pH及温度对药物释放速率都有影响;药物性质不同,释放速率及动力学行为不同。壳聚糖纳米颗粒生物相容性良好,符合生物医用材料的基本要求,可广泛应用于药物控释及基因载体等领域。     

载牛血清白蛋白壳聚糖微球的制备及其体外释药特性评价

目的:优化载牛血清白蛋白壳聚糖微球的制备工艺,并考察其体外释药特性,从而提高蛋白药物的稳定性,控制其释放速度,延长药物作用时间,提高药物生物利用度。方法:以高分子天然材料壳聚糖为载体,以离子凝胶法制备载牛血清白蛋白壳聚糖微球,通过单因素实验和正交实验设计优化制备工艺,并考察其体外释放特性。结果:扫描电子显微镜观察载牛血清白蛋白壳聚糖微球具有明显的球状结构;其最佳制备工艺为:壳聚糖分子量为300 ku、三聚磷酸钠浓度为10 mg/m L、壳聚糖浓度为3 mg/m L、牛血清白蛋白用量为30 mg,制备的微球载药率可达30.13%,体外释放可持续48 h,累积释放率达到70%,具有良好的缓释效果。结论:载牛血清白蛋白壳聚糖微球具有较高的载药量,缓释效果明显,为壳聚糖作为药物缓控释载体的进一步研究提供依据。     

聚乳酸-羟基乙酸/胶原纳米载药膜的制备及释药性研究

文章采用连续静电纺丝法制备了层层叠加的3层纳米载药膜,外层为胶原(Collagen)膜,芯层为聚乳酸-羟基乙酸(PLGA)载药膜,药物模型为盐酸四环素(TCH)。对单一的PLGA载药膜与3层载药膜进行释药性对比实验,并分别进行了表征。结果发现:戊二醛与3层载药膜中的胶原发生了反应;3层载药膜与单轴载药膜相比亲水性较好,热稳定性有所改善;3层载药膜释药前期比单轴载药膜突释小,药物的缓释时间更长。故而得出3层载药膜可作为一种良好的药物缓释载体。     

羟基喜树碱/GA-PEI-PLGA纳米粒的体外释放特性考察

目的考察载羟基喜树碱(HCPT)的甘草次酸(GA)修饰PEI-PLGA(HCPT/GA-PEI-PLGA)纳米粒的体外释药特性。方法应用乳化-溶剂挥发法制备HCPT/GA-PEI-PLGA纳米粒。采用动态透析法,考察载药纳米粒在0.5%吐温80的磷酸盐缓冲液(p H 7.4)中的释放特性,并与游离药物进行比较;对载药纳米粒的释药模型进行拟合。结果 8 h时,HCPT/GA-PEI-PLGA纳米粒中HCPT的累积释放率约为43%,显著低于游离药物的累积释放率(约80%);48 h时,载药纳米粒中HCPT的累积释放率为82%,而游离HCPT已释放完全(累积释放率达97%)。由此可见,经GA-PEI-PLGA纳米粒包载后,HCPT表现出一定的缓释作用。模型拟合结果表明,HCPT/GA-PEI-PLGA纳米粒的体外释药曲线与Higuchi模型拟合度最好,拟合方程为Q=0.1296t 1/2-0.0069(R2=0.9624)。结论 GA-PEI-PLGA纳米粒可延缓HCPT的释放,药物释放符合Higuchi方程。     

姜黄素丝素蛋白微球的制备及药物释放研究

报道了一种简单制备姜黄素丝素蛋白缓释微球的方法,并通过扫描电子显微镜、荧光显微镜、动态光散射、X射线衍射等手段研究了丝素蛋白载药微球的形成、形态大小、药物包覆及缓释性能。结果表明:制备的姜黄素丝素蛋白微球呈圆球形,粒径在210~320 nm,分散指数为0.17左右;随着丝素蛋白质量分数增加,载药微球粒径增大;而姜黄素初始质量浓度的增大,可使微球粒径略有减小;载药微球的包封率及载药质量分数分别可达40.27%及1.22%;体外药物释放实验显示,姜黄素的释放速率可以通过控制释放介质中乙醇的体积分数进行调节。     

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