可释放一氧化氮的芯-壳结构静电纺丝支架的制备（摘要）

本文制备了可释放一氧化氮（NO）的小口径人工血管.首先合成了氮烯醇化的N,N′-二丁基-1,6-己二胺（DBHD/N2O2）作为NO供体,并将其混入生物可降解材料聚己内酯中（PCL）,利用静电纺丝技术构建管状血管支架.这种血管材料展现了良好的抗血小板粘附的性能,但是却存在着细胞毒性及NO的突释现象.为了解决这两方面问题,利用同轴电纺技术构建了以PCL或明胶为壳,混有DBHD/N2O2的PCL为芯的芯-壳结构纳米纤维多孔血管支架.这种芯-壳纤维结构能够缓慢释放NO,并且细胞相容性也得到了明显的改善.     

新型亲核NO共体Diazeniumdiolate及其靶向性控释材料

新型亲核NO供体diazeniumdiolate独特的化学结构和性质，使其成为目前NO供体研究的一个热点。要使其成为更有效的药物，它的靶向性和控释性能是当前研究的重点，减小亲核试剂（多胺）的细胞毒性和亚硝胺的生成是研究的难点。本文对增强靶向性释放所采取的三个措施（聚合物控释、特定酶代谢释放和光降解释放）的近十几年国外的研究情况进行了综述。     

聚(酪氨酸酯对苯二甲酰胺)碳酸酯药物控制释放材料的研究

报道了一类生物可降解聚（酪氨酸酯对苯二甲酰胺）碳酸酯的合成和结构表征，研究了聚合物的性质和体外降解性能，并以５ 氟脲嘧啶和牛血清白蛋为模型，对它们作为药物控制释放材料的性能进行了初步评价．     

利用新型生物聚酯P3HB4HB构建原位催化NO生成人工血管材料

以新型生物聚酯P3HB4HB静电纺丝纤维支架材料为基质,通过层-层自组装技术向基质中引入γ-聚谷氨酸和聚赖氨酸,并负载含硒催化剂硒代胱胺,构建具有催化NO原位生成功能的人工血管材料,通过体外催化释放NO实验、细胞毒性检测、平滑肌细胞铺展实验考察人工血管材料的生物功能。实验结果表明,该材料具有良好的纤维多孔结构,适于作血管支架材料;通过控制有机硒的负载量可调控NO催化生成速率;而且该材料具有良好的生物相容性,能够有效抑制平滑肌细胞的黏附与铺展。     

生物可降解聚酯用作蛋白质药物控释载体

聚乳酸PLA及乳酸与羟基乙酸的共聚物PLGA,由于其良好的生物相容性以及生物降解性,可用作蛋白质类药物控释体系的载体材料,同时可延长蛋白质药物的释放.本文综述了几种生物相容性聚酯及其衍生物以及它们的形成方法:(1)在PLGA的分子链中引入亲水性的含醚键的分子如PEO、PEG,来提高聚合物的亲水性,形成PLGA嵌段共聚物;(2)将细胞可接受的片段或多肽固定在聚合物支架表面,来增强PLGA与细胞间的粘附力,得到靶向的PLGA衍生物;(3)改变PLGA载体内的酸性环境,提高蛋白质药物在载体中的稳定性,发展了支化聚酯PVA-g-PLGA,并得到均速的药物释放.以上这些方法所得到的聚酯及其衍生物,均可作为蛋白质类药物安全、可靠的载体材料.     

高效近红外聚集诱导发光纳米粒子用于生物成像的研究

基于荧光共振能量转移机理（FRET）,利用两亲性聚合物Pluronic F-127共包覆两种聚集诱导发光（Aggregation-induced Emission,AIE）材料TPABDFN和TPE-Me,制备了高效近红外发射TPABDFN/TPE-Me@F127纳米粒子.实验表明,这种聚合物纳米粒子具有很大的斯托克斯位移和较高的荧光量子效率,很好的单分散性、稳定性,以及较好的生物相容性和低的细胞毒性,对HepG2细胞进行荧光生物成像,得到很好的细胞成像效果.     

聚磷酸酯—聚氨酯药物释放材料的合成

报道了一类新型生物可降解和生物相容性药物释放材料聚磷酸酯－聚氨酯的合成和表征，研究了这类聚合物的体外降解及其对牛血清白蛋白的释放性能。     

多磺化侧链型聚芳醚的合成及性能

本文通过对聚合物的结构设计,采用亲和取代的途径制备了含有甲氧基侧链的聚芳醚聚合物,然后去醚化得到了侧链含有羟基的聚芳醚材料,最后通过接枝的方法将磺酸基团引入聚合物成功的制备出多磺化侧链型聚芳醚质子交换膜材料。此类材料表现出好的热化学稳定性, 80 oC时的质子传导率可达到0.192 S/cm,超过了Nafion 117 薄膜的传导率.同时此类材料表现出低的尺寸稳定性。因此此类材料很有希望在质子交换膜领域得到应用     

双光子激发的超分子聚合物纳米颗粒生物成像研究

将具有双-2-脲基-4[1H]-嘧啶酮（bisUPy）的β-二羰基氟硼类衍生物（BF₂-bisUPy）及卟啉衍生物（Por（Pt）-bisUPy）通过四重氢键作用组装成超分子聚合物,通过微乳液法制备成在水中均匀分散的超分子聚合物纳米颗粒（SPNP）。扫描电子显微镜形貌表征表明获得的纳米颗粒粒径约为60 nm。紫外-可见吸收光谱、荧光发射光谱及寿命衰减实验均证明纳米颗粒内BF₂-bisUPy与Por（Pt）-bisUPy可发生高效的能量传递。具有双光子吸收的BF₂-bisUPy作为能量供体,可通过荧光共振能量传递（FRET）增强双光子激发下Por（Pt）-bisUPy的发光。双光子激发荧光强度与激光功率测试表明所制备的超分子聚合物纳米颗粒具有强烈的双光子激发下的荧光及磷光双发射,这种纳米材料可进入细胞,具有优秀的生物相容性,并在双光子激发时表现出强烈的荧光和磷光双发射生物成像。     

可溶性醌胺聚合物的合成

酿胺聚合物（PAQ）是一类新型聚合物，适用于配制防水、防锈涂料，对金属有很大的亲和性［‘j．但溶解性较差［‘j．本文从分子设计出发，将一St一O一键、不对称多烷基取代脂环引人聚合物主链及侧基，增大PAQ分子内旋转自由度等提高其溶解度，合成了6种PAQ．对苯配（PBQ）按文献［3」制备，mP115～116’C；a，。二氨基丙基聚甲基硅氧烷（St—O重复次数n一8，胺值388，日本东丽化学公司）；异佛尔酮二胶（IPDA，AR，日本东京化成工业株式会社）；a，。一二氨基乙氧基聚甲基硅氧烷（St－O重复次数n二7），二缩三（1，2一丙二醇）双…     

热适性形状记忆聚合物

动态共价交联聚合物的研究具有悠久的历史,其早期的工作着眼于如何解决应力松弛带来的聚合物材料力学性能降低的问题.20世纪90年代以来,利用动态共价键来主动设计聚合物网络的特殊可适性逐渐成为研究主流,其中包括自修复和重加工性.然而,受到动态共价键的种类、通用性及所实现功能的特异性等限制,对于动态共价交联聚合物网络的研究尚停留在基础阶段.本文以本课题组近期在动态共价交联形状记忆聚合物的研究为基础,结合其他相关工作,展示了通用共价键(酯键及氨酯键)的动态可逆性,并利用其设计了具有特殊性能和潜在商业化价值的形状记忆聚合物.在此基础上,我们提出分子结构设计及宏观性能均不同于传统热塑性和热固性形状记忆聚合物的第3类形状记忆聚合物,即热适性形状记忆聚合物.     

Controlled photoinitiated release of nitric oxide from polymer films containing S-nitroso-N-acetyl-DL-penicillamine derivatized fumed silica filler

This report describes the first hydrophobic nitric oxide (NO)-releasing material that utilizes light as an external on/off trigger to control the flux of NO generated from cured polymer films. Fumed silica polymer filler particles were derivatized with S-nitroso-N-acetyl-dl-penicillamine and blended into the center layer of trilayer silicone rubber films. Nitric oxide is generated upon irradiation with light, and fluxes increase with increasing power of incident light. The ability to precisely control NO generation from this material has the potential to answer fundamental questions about the levels of NO needed to achieve desired therapeutic affects in different biomedical applications.     

Phosphorus and Silicon-Based Macromolecules as Degradable Biomedical Polymers

Synthetic polymers are indispensable in biomedical applications because they can be fabricated with consistent and reproducible properties, facile scalability, and customizable functionality to perform diverse tasks. However, currently available synthetic polymers have limitations, most notably when timely biodegradation is required. Despite there being, in principle, an entire periodic table to choose from, with the obvious exception of silicones, nearly all known synthetic polymers are combinations of carbon, nitrogen, and oxygen in the main chain. Expanding this to main-group heteroatoms can open the way to novel material properties. Herein the authors report on research to incorporate the chemically versatile and abundant silicon and phosphorus into polymers to induce cleavability into the polymer main chain. Less stable polymers, which degrade in a timely manner in mild biological environments, have considerable potential in biomedical applications. Herein the basic chemistry behind these materials is described and some recent studies into their medical applications are highlighted.     

Supramolecular Peptide/Polymer Hybrid Hydrogels for Biomedical Applications

Peptides and polymers are the “elite” building blocks in hydrogel fabrication where the typical approach consists of coupling specific peptide sequences (cell adhesive and/or enzymatically cleavable) to polymer chains aiming to obtain controlled cell responses (adhesion, migration, differentiation). However, the use of polymers and peptides as structural components for fabricating supramolecular hydrogels is less well established. Here, the literature on the design of peptide/polymer systems for self‐assembly into hybrid hydrogels, as either peptide‐polymer conjugates or combining both components individually, is reviewed. The properties (stiffness, mesh structure, responsiveness, and biocompatibility) of the hydrogels are then discussed from the viewpoint of their potential biomedical applications.     

The Use of Megamolecular Polysaccharide Sacran in Food and Biomedical Applications

Natural polymer is a frequently used polymer in various food applications and pharmaceutical formulations due to its benefits and its biocompatibility compared to synthetic polymers. One of the natural polymer groups (i.e., polysaccharide) does not only function as an additive in pharmaceutical preparations, but also as an active ingredient with pharmacological effects. In addition, several natural polymers offer potential distinct applications in gene delivery and genetic engineering. However, some of these polymers have drawbacks, such as their lack of water retention and elasticity. Sacran, one of the high-molecular-weight natural polysaccharides (megamolecular polysaccharides) derived from Aphanothece sacrum (A. sacrum), has good water retention and elasticity. Historically, sacran has been used as a dietary food. Moreover, sacran can be applied in biomedical fields as an active material, excipient, and genetic engineering material. This article discusses the characteristics, extraction, isolation procedures, and the use of sacran in food and biomedical applications.     

由聚合物门控的介孔二氧化硅基刺激响应性药物递送系统

本文主要介绍了以聚合物体系作为门控构筑的基于介孔二氧化硅纳米粒子的刺激响应性药物控释体系, 并根据聚合物类别将门控体系分为聚合物刷、 聚合物交联网络和聚合物包裹层三类. 根据聚合物“阀门”与无机纳米粒子的共价或非共价连接方式, 综述了这些杂化材料在不同外界刺激作用下的药物控制释放行为, 并给出该领域所面临的机遇和挑战.     

导电聚合物的纳米结构及其在生物医学领域的应用

由于表面效应、小尺寸效应和量子效应,使纳米结构的导电聚合物材料与传统聚合物材料相比,显示出更优越的性能。基于神经组织对电场和电刺激敏感性,使得导电聚合物纳米材料在生物医学应用方面很有前景。本文综述了纳米结构的导电聚合物的合成方法,及其在生物医学领域的应用。合成方法主要关注于硬模板法、软模板法和无模板自组装法,以及这些方法中导电聚合物纳米结构的形成机理。总结了具有纳米结构的导电聚合物,如纳米颗粒、纳米纤维和纳米管等作为神经电极涂层材料和生物传感器等方面的应用。     

可释放一氧化氮纳米材料的研究进展

一氧化氮(NO)是一种内源性双原子分子,在许多生理学和病理学过程中起了关键的调节作用,包括血管平滑肌松弛、免疫反应、神经传递、呼吸作用、细胞凋亡等。NO的生理调节作用在很大程度上依赖于NO释放的位置、时间以及剂量。开发出能够储存NO并且在指定的地点和时间释放需求量的NO的纳米运输平台是非常重要的研究课题。此篇综述,主要介绍近期我们课题组和其他研究人员在NO控制释放以及生物学应用的研究进展。本文首先概述了几类具有应用前景的外源性NO供体,如偶氮二醇烯、亚硝基硫醇、硝基苯和金属亚硝酰化合物。然后,重点讨论了结合NO供体和纳米平台在控制释放NO和生物医学的潜在应用。     

Hofmeister effects of anions on self-assembled thermogels

Thermogels are temperature-responsive soft biomaterials with numerous biomedical applications. They possess high water content and can spontaneously gelate by forming non-covalent physical crosslinks between their constituent amphiphilic polymers when warmed. However, despite the ubiquity of salts in biological fluids and buffer media, the influence of salts on thermogelling polymers and the overall physical properties of the resulting hydrogels are poorly understood. Herein, we elucidate the effects of common inorganic salts on the gelation and micellization properties of a thermogelling polymer containing poly(ethylene glycol), poly(propylene glycol), and poly(caprolactone) components. The identity of the salts' anions and their concentrations was found to exhibit significant effects on the thermogel properties, in some cases being able to decrease the sol-to-gel phase transition by up to 10 °C. We demonstrate that these notable influences are likely brought about by the changes in solvation of both the polymer's hydrophobic and hydrophilic segments, as well as by direct interactions of poorly hydrated anions with the hydrophobic polymer segments. Our findings show that the effects of salts on amphiphilic thermogelling polymers are non-negligible and hence need to be taken into account for engineering and optimization of thermogel properties for different biomedical applications.     

Advances in polymer and polymeric nanostructures for protein conjugation

Linear polymers have been considered the best molecular structures for the formation of efficient protein conjugates due to their biological advantages, synthetic convenience and ease of functionalization. In recent years, much attention has been dedicated to develop synthetic strategies that produce the most control over protein conjugation utilizing linear polymers as scaffolds. As a result, different conjugate models, such as semitelechelic, homotelechelic, heterotelechelic and branched or star polymer conjugates, have been obtained that take advantage of these well-controlled synthetic strategies. Development of protein conjugates using nanostructures and the formation of said nanostructures from protein–polymer bioconjugates are other areas in the protein bioconjugation field. Although several polymer–protein technologies have been developed from these discoveries, few review articles have focused on the design and function of these polymers and nanostructures. This review will highlight some recent advances in protein-linear polymer technologies that employ protein covalent conjugation and successful protein-nanostructure bioconjugates (covalent conjugation as well) that have shown great potential for biological applications.