功能化磁性高分子复合微球的研究进展

功能化磁性高分子复合微球作为一种新型功能材料,在许多领域具有广阔的应用前景。本文对近年来功能化磁性高分子复合微球的制备方法进行了总结,对当前不同方法的优缺点进行了评价与分析;对功能化磁性高分子复合微球在生物工程领域,医学领域,环境、食品领域和功能材料领域进行了阐述。并综合分析了磁性微球在各个领域的优势及已经取得的成果。最后,展望了功能化磁性高分子复合微球的发展前景,提出自己的观点,并列出亟待解决的四个问题。     

磁性高分子微球用于固定化酶的研究进展生物材料结构及性质的基础研究及其应用于药物的控制释放

磁性高分子微球是近20年来发展起来的一种新型功能高分子材料,并已在生物化工、细胞学、生物医学工程等领域得到了广泛应用。本文主要介绍磁性高分子微球的制备和性质以及在固定化酶中的应用。     

磁性高分子微球用于固定化酶的研究进展：生物材料结构及？…

磁性高分子微球是近２０年来发展起来的一种新型功能高分子材料,并已在生物化工、细胞学、生物医学工程等领域得到了广泛应用。本文主要介绍磁性高分子微球的制备和性质以及在固定化酶中的应用。     

磁性高分子微球用于固定化酶的研究进展

磁性高分子微球是近20年来发展起来的一种新型功能高分子材料,并已在生物化工、细胞学、生物医学工程等领域得到了广泛应用.本文主要介绍磁性高分子微球的制备和性质以及在固定化酶中的应用.     

磁性高分子微球的制备和应用研究进展

磁性高分子微球是近２０年来研究的一类新型功能材料，在生物医学，细胞学和生物工程等领域有着广泛的应用前景，本文对磁性高分子微球的性质，制备方法及功能经方法作了详细评述，介绍了磁性高分子微球在细胞分离，固定化酶，免疫测定，生物导弹，ＤＮＡ分离及核酸杂交等领域的应用。     

磁性分子印迹聚合物核壳微球的制备及应用*

分子印迹技术是综合高分子化学、生物化学等学科发展起来的一门边缘学科。通过分子印迹技术制备的聚合物具有吸附选择性好、色谱效率高、便于功能设计等优点,在色谱分离、固相萃取、传感器、药物控释等领域得到了广泛的应用。磁性聚合物微球是近年发展起来的一种新型多功能材料,已广泛应用于生物分离、药物控释、疾病诊断等领域。在磁性粒子表面进行分子印迹制备的磁性分子印迹聚合物核壳微球,兼有良好的超顺磁性和高选择吸附性两大优点,具有广阔的应用前景。本文重点综述了磁性分子印迹聚合物核壳微球的制备方法以及在化学分析、生物分离和药物控释方面应用的研究进展,并指出了该领域工作存在的问题及今后的发展方向。     

P(St-GMA)/Fe3O4磁性聚合物微球的制备及表征

采用沉淀法制备了Fe3O4纳米粒子, 以苯乙烯(St)、甲基丙烯酸缩水甘油酯(GMA)为聚合单体, 使用分散聚合法制备了P(St-GMA)/Fe3O4磁性聚合物微球. 分析了Fe3O4粒子的形貌和结构. 研究了制备条件对磁性聚合物微球磁含量的影响. 采用FTIR, XRD, TG及TEM等手段对磁性聚合物微球的微观结构及形貌、磁含量等进行了分析表征. 研究结果表明, 制备的磁性聚合物微球粒径均一, 磁含量高达74%.     

分子印迹聚合物微球的制备及表征技术

分子印迹聚合物微球作为一种具有分子识别能力的新型高分子材料,以其吸附选择性好、色谱效率高、便于功能设计等优点在固相萃取、药物手性分离等领域取得了应用.本文介绍了分子印迹聚合物微球的主要制备方法,比较了不同的聚合物微球制备方法用于分子印迹技术中的特点,同时针对不同聚合方法对分子印迹聚合物微球性能的影响作了相应评述,此外对其结构与性能的表征方法也作了较为详细的介绍,在此基础上分析了存在的问题及今后的发展方向.     

超顺磁性高分子微球的制备与表征

用化学共沉淀方法制备了Fe3O4纳米微粒,并用油酸(十八烯酸)和十二烷基苯磺酸钠为双层表面活性剂进行表面修饰,制备了稳定的水分散性纳米Fe3O4可聚合磁流体.在Fe3O4磁流体存在下,将苯乙烯与甲基丙烯酸通过乳液聚合方法制备了磁性高分子微球.透射电镜研究表明,Fe3O4微粒的平均粒径在10nm左右,乳液聚合形成的磁性高分子微球的粒径平均约为130nm;用超导量子干涉仪对微粒及高分子微球进行了磁性表征,结果表明,合成的Fe3O4纳米微粒以及磁性高分子微球均具有超顺磁性.同时,还用红外光谱及X射线衍射表征了磁性高分子微球的化学成分和晶体结构.用热失重方法测得磁性高分子微球中磁性物质的含量为23.6%.     

磁性高分子微球

对磁性高分子微球的研究现状进行了综述,详细探讨了目前常用的各种合成制备方法,并对各种方法的优缺点进行了分析。在此基础上,对磁性高分子微球在细胞分离、有机合成、环境/食品微生物检测等领域的最新应用进展及存在的问题进行了分析,指出了该领域今后的研究方向。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.