磷酰胆碱色谱固定相的制备及其在分离生物大分子中的应用

以三氯氧磷、氯化胆碱和甲基丙烯酸-2-羟乙酯(HEMA)为原料合成了含磷酰胆碱的单体2-甲基丙烯酰氧乙基磷酰胆碱(MPC). 在硅胶表面嫁接聚合MPC, 得到磷酰胆碱两性离子交换色谱填料. 研究了该填料对标准蛋白的分离性能及pH对蛋白质保留的影响. 结果表明, 该填料对溶菌酶和牛血清白蛋白的动态吸附容量分别为13.8和18.7 mg/g, 其基质磷酰胆碱色谱固定相可同时基线分离两种酸性和两种碱性蛋白.     

血液相容生医材料的合成研究15——苯乙烯型磺酸铵内盐单体的合成及其聚合物的抗血小板粘附性能

两性离子不凝血生物材料;血液相容生医材料的合成研究15——苯乙烯型磺酸铵内盐单体的合成及其聚合物的抗血小板粘附性能     

聚氨酯表面构建磺铵两性离子结构及其抗血小板粘附性的研究

通过己二异氰酸酯(HDI)在聚醚氨酯(PU)表面构建磺铵两性离子结构,以改善其不凝血性能,首先用HDI活化PU表面,生成PU-NCO衍生物;然后通过N,N-二甲基乙醇胺(DMEEA)中的—OH和PU表面的—NCO反应生成PU-N(CH_3)_2;最后用丙磺酸内酯(PS)进行开环.生成磺铵两性离子结构,用ATR-IR表征了各步反应,对构建前后材料的抗血小板粘附性能进行了比较,结果表明,磺铵两性离子结构具有优异的抗血小板粘附性。     

2-甲基丙烯酰氧基乙基磷酰胆碱单全及其聚合物的合成与应用

近年来,生物医用高分子材料的生物相容性研究备受关注.基于仿细胞膜外层结构设计合成的2-甲基丙烯酰氧基乙基磷酰胆碱(MPC)及其聚合物研究已成为一个新热点.大量研究结果表明,用MPC聚合物修饰生物材料表面,可获得良好的血液相容性和组织相容性.本文综述了MPC单体及其聚合物的合成以及其在人造器官、组织工程、血液净化、药物控释与基因治疗、固定化酶、生物传感器等方面的应用,探讨了MPC聚合物研究应用的发展趋势.     

2-甲基丙烯酰氧基乙基磷酰胆碱单体及其聚合物的合成与应用

近年来,生物医用高分子材料的生物相容性研究备受关注。基于仿细胞膜外层结构设计合成的2-甲基丙烯酰氧基乙基磷酰胆碱（MPC）及其聚合物研究已成为一个新热点。大量研究结果表明,用MPC聚合物修饰生物材料表面,可获得良好的血液相容性和组织相容性。本文综述了MPC单体及其聚合物的合成以及其在人造器官、组织工程、血液净化、药物控释与基因治疗、固定化酶、生物传感器等方面的应用,探讨了MPC聚合物研究应用的发展趋势。     

血液相溶材料的合成研究(Ⅶ)-一类新的抗血小板粘附高分子材料

不凝血性 (Nonthrombogenicity)又称抗凝血性 (Antithrombogenicity) ,是指材料不会触发血液凝固的能力 .如何提高不凝血性一直是高分子生物材料研究的主要任务和中心内容 [1～ 3 ] .但目前抗凝血性最好的三类抗凝血材料 ,即聚乙二醇衍生物 (PEO)、聚磷酰胆碱及肝素化材料等 [4～ 10 ] 仍不能满足心血管医用装置的需要 .材料界面血小板的粘附和活化是导致凝血的重要因素 .活化的血小板不仅可激活多种凝血因子 ,也是材料表面血栓的重要组成部分 .因此 ,对材料界面血小板粘附行为的研究可初步评价材料的血液相容性 [11,12 ] .根据“维持正常…     

聚氨酯表面构建磺胺两性离子结构及其抗血小板粘附性的研究

通过己二异氰酸酯(HDI)在聚醚氨酯(PU)表面构建磺铵两性离子结构，以改善其不凝血性能。首先用HDI活化PU表面，生成PU—NCO衍生物；然后通过N，N—二甲基乙醇胺(DMEEA)中的-OH和PU表面的-NCO反应生成PU—N（CH3）2；最后用丙磺酸内酯(PS)进行开环。生成磺铵两性离子结构。用ATR—IR表征了各步反应，对构建前后材料的抗血小板粘附性能进行了比较，结果表明，磺铵两性离子结构具有优异的抗血小板粘附性。     

两性离子表面活性剂的合成及其表面性质

合成了一类含季铵基和磺酸基结构的非对称Gemini两性离子表面活性剂;利用红外光谱、质谱、离子定性试验验证了合成产物的分子结构,并测定了其表面性质.结果表明,目标产物的分子结构符合设计预期;五种非对称Gemini两性离子表面活性剂的表面张力在30mN/m左右,临界胶束浓度达到10-4~10-5数量级.此外,虽然非对称Gemini两性离子表面活性剂的起泡性能比相应单链型表面活性剂的稍差,但其稳泡性明显优于后者.     

血液相容材料的合成研究Ⅷ.磺铵两性离子单体在聚醚氨酯表面的臭氧活化接枝

生物相容性 ,特别是血液相容性是生物医用材料极其重要的性能[1] .提高不凝血性一直是生物材料研究与发展 (Ｒ Ｄ)的主要内容之一 ,半个多世纪来 ,不凝血材料的Ｒ Ｄ已取得了很大的发展[2 ] .但还不能满足心血管植入物 (Ｃａｒｄｉｏｖａｓｃｕｌａｒｉｍｐｌａｎｔｓ)及心血管医物 (Ｃａｒｄｉｏｖａｓｃｕｌａｒｄｅｖｉｃｅｓ)对不凝血性的需要 .Ｒａｔｎｅｒ[3 ] 在最近一次的血液相容性问题研讨会上再次强调了不凝血材料研究的紧迫性 .会议的报告也反映了该领域的研究现状 ,并提出了今后要研究的问题等 .目前不凝血性较好的材料仅有聚…     

抗凝血高分子生物材料的表面设计

生物材料,尤其是血液接触材料,满足抗凝血性能是临床应用的首要前提。采用表面改性策略来提高材料表面的抗凝血性能,简单易行。表面改性主要包括表面设计和方法设计两个方面。本文对抗凝血性高分子生物材料的表面设计各类方法进行了综述,其中包括材料表面的微相分离结构、材料的负电荷表面设计、材料的亲(疏)水性表面设计、材料的生物活性化表面设计和材料的内皮细胞化表面设计等等,并重点阐述了两性离子的抗凝血表面设计。     

Functionalizable biodegradable photocrosslinked elastomers based on 2‐oxepane‐1,5‐dione

The use of aliphatic polyesters for biomedical applications is limited by the lack of functionality of their backbones. The aim of the following study was to develop a novel elastic scaffold material containing functional groups to be used for future derivatization to tether peptide ligands to support cell adhesion, migration, and differentiation. The elastomer was based on three‐arm star copolymers composed of ε‐caprolactone and a functionalized ε‐caprolactone, 2‐oxepane‐1,5‐dione, and end‐terminated with acrylate groups. The elastomer thus contains a ketone and two approaches were examined for obtaining a photocrosslinkable elastomer containing functional groups: crosslinking followed by ketone reduction using sodium borohydride to generate pendant hydroxyl groups, and reaction of the ketone with hydrazines. Reduction of the ketone lead to degradation of the elastomer through transesterification and ethanolate mediated cleavage of the polymer backbone. Reaction with hydrazines did not degrade the polymer and resulted in efficient functionalization of the elastomer. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8191–8199, 2008     

Synthesis of multi-hydroxyl and sulfonyl dual-functionalized room temperature ionic liquids

Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ionic liquids have been synthesized. The hydroxyl groups of the synthesized substances were confirmed by the 1H NMR measurement. These zwitterionic salts and ionic liquids may be used for synthesizing other functionalized ionic liquids or ionic liquid-polymer (polyelectrolyte).     

Lactamomethylation of alkylphenols: Synthesis and quantum-chemical study of the reaction pathway

Six novel lactamomethyl derivatives of 2,5-dimethylphenol and 2,3,5-trimethylphenol were prepared with moderate yields by the reaction of corresponding phenols with 1-(hydroxymethyl)lactams in the presence of an acid catalyst. In all cases, the substitution occurred at position 4 to the phenolic hydroxyl group. The structures of all synthesized compounds were confirmed by FT-IR, ¹H and ¹³C NMR, 2D NMR and elemental analysis. The selectivity and possible pathways of the lactamomethylation reaction were studied by quantum-chemical methods. In silico calculations showed that the substitution at para-position to the hydroxyl group of the corresponding phenols was more preferable due to the higher stability of forming intermediates.     

Intramolecular hydrogen bonding (P=O--H) stabilizes the chair conformation of six-membered ring phosphates

[reaction: see text] Six-membered cyclic phosphates (2-phenoxy-2-oxo-1,3,2-dioxaphosphorinanes) bearing an internal protected or unprotected hydroxyl group were designed, synthesized, and studied by NMR and computational methods. Selective opening of O-isopropylidene-protected 1,2-diols at the primary site was achieved with either triethylsilane or trimethylallylsilane in the presence of BF3.OEt2. Applied to 5,6-O-isopropylidenepentofuranosides, this reaction gave rise to the formation of the corresponding 1,3-diol precursors for the six-membered ring phosphates containing an O-isopropyl or O-1,1-dimethyl-3-butenyl functional group at C-6. The O-1,1-dimethyl-3-butenyl protecting group was efficiently removed after the phosphorylation with BF3.OEt2, and the six-membered cyclic phosphates containing free hydroxyl groups were obtained. A cyclic phosphate with a free hydroxyl group oriented cis to the phosphoryl group shows a vicinal coupling constant 3J(HP) that is in accordance with the chair conformation. This is due to the formation of a seven-membered intramolecular hydrogen-bonded ring structure that stabilizes the chair conformation. Thus, the strong tendency of the phenoxy group to be in an axial position is diminished by the internal hydrogen bonding interaction. Computational studies provided strong support for the experimental observation.     

IBX/n-Bu4NBr/CH2Cl2-H2O: a new mild system for selective oxidation of secondary alcohols

A new alternative system for the chemoselective oxidation of secondary hydroxyl group to ketone with IBX/n-Bu₄NBr in CH₂Cl₂-H₂O has been developed. Under the reaction conditions, the secondary hydroxyl group was highly chemoselectively oxidized to the corresponding ketone, in moderate to good yields at rt, in the presence of primary hydroxyl group within the same molecule.     

1-苯基-3-甲基-4-萘乙酰基-吡唑啉酮-5 (PMNAP)缩2-氨基苯并咪唑(2-AB)席夫碱及其过渡金属配合物的合成、光谱表征与质谱鉴定

在非水溶剂中合成出一种新型席夫碱试剂(H2L): 1-苯基-3-甲基-4-萘乙酰基-吡唑啉酮-5 (PMNAP)缩2-氨基苯并咪唑(2-AB)及其过渡金属铜、铅、镍和钴配合物. 由元素分析、综合滴定和质谱数据推测出配合物的组成为ML•H2O, 通过红外光谱、紫外光谱、热重谱和核磁共振氢谱对配体和配合物进行了结构表征, 同时建立了合成体系的液相色谱分离和质谱鉴定方法, 在线得到了配体共存的三种异构体和目标配合物及其相应的质谱信息. 综合各种分析结果显示: 配体在测试条件下以酮式和烯醇式结构共存, 配位时酮式可能转化为烯醇式结构, 按去质子的方式以吡唑啉酮环羟基和H2O上的两个O原子以及亚胺基上的N原子和苯并咪唑环上的含氢N原子与中心离子成键, 配合物的配位数为4.     

Selective and Efficient Oxidation of Aldehydes to Their Corresponding Carboxylic Acids Using H2O2/HCl in the Presence of Hydroxylamine Hydrochloride

A wide variety of aldehydes were efficiently converted to their corresponding carboxylic acids in high yields using H₂O₂/HCl in the presence of hydroxylamine hydrochloride. In addition, selective oxidation of aldehydes in the presence of other functional groups such as hydroxyl group, carbon‐carbon double bond and other heteroatoms can be considered a noteworthy advantage of this method.     

Synthesis and characterization of functional polyesters tailored for biomedical applications

This work aimed at the development of bioactive polymeric materials to be used for targeted drug delivery and tissue engineering applications. The proposed strategy was based on the design of macromolecular systems whose functionality can be easily modified. Polyesters containing side‐chain end capped by primary hydroxyl groups were synthesized by polyaddition of oxetanes and carboxylic anhydrides catalyzed by quaternary onium salts. The polyaddition of bis(oxetane) with different dicarboxylic acids was also investigated. In all cases, oxetane monomers contained one hydroxyl group either free or protected by a benzyl group. The polymer yield and molecular weight were relatively high when aromatic anhydrides were used. In all other cases, low conversions or no polymerization at all were obtained. In a parallel research line, several alkanols were successfully employed to synthesize different α,β′,β‐trisubstituted‐β‐lactones. These monomers were prepared in five steps starting from diethyl oxalpropionate according to established synthetic routes. Final yields depended on both preparation method and side‐chain structure. By using quaternary ammonium salts as catalysts, the synthesized functional lactones underwent anionic ring opening polymerization leading to the corresponding homopolymers and copolymers in fairly good yields. The prepared polymeric materials were extensively characterized by spectroscopic techniques, size exclusion chromatography, and thermal analysis. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2459–2476, 2008     

SnCl4/SiO2: An Efficient Heterogeneous Alternative for One‐Pot Synthesis of β‐Acetamidoketones

Enolizable ketones have been reacted in a one‐pot method with aromatic aldehydes, acetyl chloride and acetonitrile at room temperature in the presence of SnCl₄/SiO₂ to furnish the corresponding β‐acet‐amidoketones in improved yields. Acetylation of an aromatic hydroxyl group was observed while using 4‐hydroxybenzaldehyde or vanillin and the corresponding β‐acetamidoketones were isolated in an excellent yield.     

Solid-phase Synthesis of a Novel Kind of Hydroxylated Heterocyclic Ketene Aminals

An efficient solid-phase synthesis method for novel heterocyclic ketene aminals containing a hydroxyl group has been developed. The loading of the substrate on the resin through the hydroxyl group and the protection of the amine by the Schiff base were the key steps in the synthesis.