聚乙二醇单甲醚接枝壳聚糖自组装纳米球的制备

目的:合成聚乙二醇单甲醚接枝壳聚糖(monomethoxy poly(ethylene glycol)-grafted-chitosan,mPEG-g- CS),并制备自组装纳米球。方法:利用甲醛连接法将聚乙二醇单甲醚(monomethoxy poly(ethylene glycol),mPEG)接枝干壳聚糖(ehitosan,CS)分子,得到聚乙二醇(poly(ethylene glycol),PEG)改性的壳聚糖衍生物,并通过傅立叶红外光谱仪(Fourier transform infrared spectroscopy,FT-IR),核磁共振仪(proton nuclear magnetic resonance,~1H-NMR)对产物进行结构表征;采用超声透析法制备自组装纳米球,并通过透射电镜(transmission electron microscopy,TEM),动态激光粒度分析仪(dynamic laser light scattering,DLLS)表征了纳米球的形态和粒径;以芘为荧光探针,通过荧光检测分析测定了mPEG-g-CS的临界胶束浓度(critical micellar concentration,CMC)。结果:通过FT-IR,~1H- NMR确证了接枝产物的存在;mPEG-g-CS在水溶液中能够自组装形成球状纳米胶束,平均粒径为250 nm。结论:通过甲醛连接法制备mPEG-g-CS,具有制备方法简捷、反应周期短、易操作的优点。利用该产物制备的纳米球有望成为长循环纳米药物载体

In vitro study of cholesterol succinyl chitosan anchored liposomes as a carrier for epirubicin

背景:多糖"锚定"脂质体在抗肿瘤药物、蛋白以及基因的传输领域有着极其重要的理论及应用价值,国外已有较多机构在进行相关的研究。目的:通过"锚定"的方式制备胆甾醇琥珀酰基壳聚糖锚定脂质体,并以表阿霉素作为模型药物,考察其对包载药物体外释放性质的影响。设计、时间及地点:体外实验,于2006-09/2008-05在天津市生物医学材料重点实验室完成。材料:以壳聚糖为原料,合成胆甾醇琥珀酰基壳聚糖,并采用胶体滴定法测定其胆甾醇基取代度。方法:采用pH梯度法制备表阿霉素脂质体,然后通过共孵育的方法合成了取代度为2.80%,5.58%和8.00%的载药胆甾醇琥珀酰基壳聚糖锚定脂质体。主要观察指标:荧光分光光度计检测药物浓度;透射电镜观察脂质体形态;亚微米粒度及电位分析仪检测脂质体的粒径大小、分布和电位;动态透析法考察包载药物表阿霉素在胆甾醇琥珀酰基壳聚糖锚定脂质体中的体外释放特征。结果:胆甾醇琥珀酰基壳聚糖锚定脂质体为规则球状形态,呈现典型的核壳结构,粒径为245.4~279.7nm,zeta电位为+21.09~+25.48mV;和载药脂质体及壳聚糖包衣脂质体相比,CHCS锚定脂质体能明显延缓表阿霉素的体外释放,在胆甾醇基取... 【英文摘要】 BACKGROUND: Polysaccharides anchored liposomes play an extremely important role in the fields of antitumor drug, protein and gene transmission. Related research is also present abroad. OBJECTIVE: To prepare cholesterol succinyl chitosan (CHCS) anchored liposomes, and to investigate the effect of CHCS anchored liposomes on the release property in vitro of loading drugs taking epirubicin as a model drug. DESIGN, TIME AND SETTING: A study in vitro was performed in the Key Laboratory of Biomedical Materials o

类泛素蛋白及其中文命名

泛素家族包括泛素及类泛素蛋白,约20种成员蛋白.近年来,泛素家族领域取得了迅猛发展,并已与生物学及医学研究的各个领域相互交叉.泛素家族介导的蛋白质降解和细胞自噬机制的发现分别于2004和2016年获得诺贝尔奖.但是,类泛素蛋白并没有统一规范的中文译名. 2018年4月9日在苏州召开的《泛素家族介导的蛋白质降解和细胞自噬》专著的编委会上,部分作者讨论了类泛素蛋白的中文命名问题,并在随后的\"泛素家族、自噬与疾病\"(Ubiquitinfamily,autophagy anddiseases)苏州会议上提出了类泛素蛋白中文翻译草案,此草案在参加该会议的国内学者及海外华人学者间取得了高度共识.冷泉港亚洲\"泛素家族、自噬与疾病\"苏州会议是由美国冷泉港实验室主办、两年一度、面向全球的英文会议.该会议在海内外华人学者中具有广泛影响,因此,参会华人学者的意见具有一定的代表性.本文介绍了10个类别的类泛素蛋白的中文命名,系统总结了它们的结构特点,并比较了参与各种类泛素化修饰的酶和它们的生物学功能.文章由45名从事该领域研究的专家合作撰写,其中包括中国工程院院士1名,相关学者4名,长江学者3名,国家杰出青年科学基金获得者18名和美国知名高校华人教授4名.他们绝大多数是参加编写即将由科学出版社出版的专著《泛素家族介导的蛋白质降解和细胞自噬》的专家

二维GaAs基光子晶体微腔的制作与光谱特性分析

研究了以InAs量子点为有源区的二维GaAs基光子晶体微腔的设计与制作,测试并分析了室温下微腔的光谱特性.观察到了波长约为1137nm,谱线半高宽度约为1nm的尖锐低阶谐振模式发光峰.我们比较了不同刻蚀条件下光子晶体微腔的发光谱线,结果表明空气孔洞截面的垂直度是影响光子晶体微腔发光特性的重要因素之一.通过调节干法刻蚀工艺,改变空气孔半径与晶格常数的比率,可以在较大范围内调节谐振模式发光峰位置,达到谐振模式与量子点发光峰调谐的目

Chitosan-based self-assembled nanomicelles as a novel carrier for paclitaxel

【中文摘要】以N-胆甾醇琥珀酰基-O-羧甲基壳聚糖(CCMC,胆甾醇基取代度6.9%)为原料,在水溶液中通过探头超声处理制备其自组装凝胶纳米胶束,采用稳态荧光探针法考察临界胶束浓度,并通过透射电镜和动态激光散射仪检测胶束的形态大小.以紫杉醇为模型药物,采用透析法制备载药CCMC纳米胶束,并通过高效液相色谱法(HPLC)考察其在纳米胶束中的包载及释放情况.结果显示,CCMC为两亲性高分子,在水溶液中能形成粒径为198.4 nm的规则球状胶束,临界胶束浓度为0.018 mg/mL.紫杉醇顺利包载于CCMC-纳米胶束内,载药量高达34.9%;随着载药量的增加,胶束粒径呈增大的趋势.体外释放实验结果显示,CCMC纳米胶束能延缓紫杉醇的释放,释药速度和释放介质pH值密切相关. 【Abstract】Self-assembled nanomicelles of N-cholesterol succinyl O-carboxymethyl chitosan (CCMC) were prepared by probe sonication method. The amphiphilic property and the critical micelle concentration(cmc) of CCMC were determined by fluorescence probe technique; the morphology and the size of CCMC self-assembled nanomicelles were analyzed by transmission electron microscopy(TEM) and the dynamic laser light scattering (LLS). Paclitaxel(PTX), being used as model drug, was entrapped into CCMC self-assembled nanomicelles by dialysis method. The drug loading and release properties were estimated by high performance liquid chromatography( HPLC). The results show that CCMC was an amphiphilic polymer and formed regularly spherical nanomicelles( mean diameter = 198.4 nm) in aqueous medium by self-assembly, and the cmc value of CCMC was 0.018 mg/mL. PTX-loading CCMC self-assembled nanomicelles were successfully prepared, with drug loading content as high as 34.9%, and their mean diameter increased with increasing the drug loading content. PTX continuously released. from CCMC self-assembled nanomicelles in the release media of phosphate buffered saline(PBS) solutions, and its release was sensitive to the pH of the release media

Preparation and Characterization of PLGA Nanospheres Surface Modified with Biotinylated Chitosan

【中文摘要】合成了生物素化壳聚糖（Bio-CS)，并通过核磁共振（1H NMR)及电感耦合等离子体光质谱法（ICP-MS）对其进行结构确证。采用溶剂挥发法（W1/O/W2）制备聚乳酸-羟基乙醇酸（PLGA)纳米粒，并通过共价交联法对纳米粒进行Bio-CS表面修饰。未修饰的PLGA纳米粒在扫描电镜下观察呈规则球状形态，平均粒径为（248.4±21.0）nm，Zeta电势为-（21.21±2.13）mV，Bio-CS修饰后的PLGA纳米粒保持球状形态，平均粒径为（268.3±23.4）nm，Zeta电势为（25.45±2.59）mV。采用X射线光电子能谱（XPS)以及试剂盒对纳米粒表面生物素进行定性及定量研究，结果显示，经过Bio-CS修饰后的纳米粒表面含有N,S元素，生物素取代为31%的Bio-CS修饰的PLGA纳米粒，其表面生物素含量为（1.36±0.34）μmol/100mg纳米粒。 【Abstract】Biotinylated chitosan (Bio-CS conjugates or Bio-CS) were synthesized and characterized. The degree of substitution(DS), as defined as the number of biotin per 100 anhydroglucose units of CS, was determined by (1)H NMR and ICP. Poly (lactic-co-glycolic acid) (PLGA) nanospheres were prepared by a solvent evaporation technique(W(1)/O/W(2)). The surface of PLGA nanosphere was modified with Bio-CS by covalent binding. PLGA nanospheres were almost spherical in shape under the scanning electron microscopy (SEM) observation, and their mean diameter determined by the laser light scattering technique was (248.4 +/- 21.0) urn. Bio-CS modified PLGA nanospheres were also spherical in shape; their mean diameter and Zeta potential value were (268.3 +/- 23.4) nm and (21.21 +/- 2.13) mV, respectively. The surface chemistry of nanospheres was quantitatively studied by X-ray photoelectron spectroscopy(XPS). The results show the N region corresponding to the primary amide of CS and the S region corresponding to the biotin, indicating that PLGA nanospheres were successfully surface-modified with Bio-CS. The content of biotin on the surface of Bio-CS modified PLGA nanospheres with DS of biotin of 31% was determined using a commercially available Quant * Tag (TM) Biotin Kit and its value was (1.36 +/- 0.34) mol/100 mg