两亲性含糖嵌段共聚物在水中分子聚集形态的转变

两亲性嵌段共聚物在不同的介质中可形成不同形态的有序分子聚集体［１～３］．当其亲水段长度远大于亲油段时,在水中主要形成球形胶束［１］;但当亲水段长度远小于亲油段时,则形成多种形态的分子聚集体,即所谓的“ｃｒｅｗ－ｃｕｔ”聚集体,如球形、柱状、层状、囊泡和管状等［４］．Ｅｉｓｅｎｂｅｒｇ等［４～６］详细研究了聚苯乙烯－ｂ－聚丙烯酸在水中的“ｃｒｅｗ－ｃｕｔ”聚集体,发现聚集体的形态和多种因素有关,如共聚物组成、溶剂、ｐＨ值和金属离子等．以两亲分子形成的囊泡不但可以用来模拟生物膜的结构,而且在药物载体…     

杯芳烃衍生聚合物用作毛细管气相色谱固定相的研究

合成了两种不同构象的杯芳烃衍生聚合物（杯芳冠醚聚硅氧烷ｃ－ｃ［４］ｃ５－ｐｓｏ和二乙氧基杯［４］芳烃聚硅氧烷ｐ－ｃ［４］－ｐｓｏ），并将其用作毛细管气相色谱固定液，使用温度高达３２０℃，对不同的极性化合物，特别是对酚类异构体有很好的分离能力。同时也研究了分离机理。     

1a,3-二苯基-1,1,4,4-四氯-1a,2,3,4-四氢-1H-吖丙啶并[2,1-e][1,6]苯并硫氮杂辛因的合成及晶体结构

苯并杂类化合物为常用镇静剂及治疗心血管疾病和抗病毒的药物［１～３］,苯并杂与五六元杂环并合形成的三环化合物也是重要的药用杂环化合物,如１,４－苯并二氮杂与１,２,４－三唑并合形成的三环化合物为常用的治疗中枢神经系统疾病药物［４］．而吖丙啶与１,...     

PPV-PDMeOPV共聚物发光性质的实验和理论研究

具有优良电致发光性能的有机聚合物材料的研制及其发光性能和应用的研究是９０年代新兴的高科技领域．聚对苯乙炔［Ｐｏｌｙ（ｐ－ｐｈｅｎｙｌｅｎｅｖｉｎｙｌｅｎｅ）,缩写为ＰＰＶ,又称聚苯撑乙烯］是这一领域最先研制出来的具有代表性的材料［１,２］．为改变ＰＰ...     

合成抗病毒母体三羟基核苷的新方法

三羟基核苷因其具有良好的抗病毒性能及作为核酸代谢作用的抑制剂而受到人们的关注．文献报道的合成方法［１～３］因反应需避光，温度控制要求严格，中间体二醛不稳定［４］，给操作带来困难．产物不易纯化，一般局限于使用离子交换色谱法［５］，而按此方法得到的无环核...     

聚合物材料缺口冲击强度与断面粗糙度参数Rs的关系

金属材料断面粗糙度的测定描述及其与材料性能间的关系已有很多报道,研究结果表明,随断面粗糙度表征参量（分形维数ＤＦ,表面粗糙度参数ＲＳ）增大,金属材料的一些宏观力学性能（断裂韧性ＫＩＣ,冲击韧性ａＫ,疲劳门槛值ΔＫｔｈ等）增高,但这些研究都较少涉及材料的断裂机制［１～３］．聚合物材料断面粗糙度的定量研究较少,有关聚合物材料断面粗糙度与材料韧性间关系的定量结论也不一致［４,５］,体现出聚合物材料断面粗糙度定量分析的复杂性．本文通过对不同试验温度下几种聚合物材料冲击断面粗糙度的定量测定,研究了聚合物材…     

聚苯乙烯对酞菁铜颜料微胶囊化的研究

自１９５４年美国首先将微胶囊化应用于无碳复写纸后［１,２］,这项技术在药物、农药、食品及染料等方面已得到广泛应用［３］．微胶囊（ＭＣ）直径通常是１～５０００μｍ,构造分为囊壁和囊芯两部分［４］．囊壁材料大多使用高分子材料,少数用无机物［５］．有机颜料...     

含高氯酸锂的IPN固体电解质研究

高分子固体电解质（ｐｏｌｙｍｅｒｉｃｓｏｌｉｄｅｌｅｃ－ｔｒｏｌｙｔｅ）由于其潜在的应用价值，人们对它进行了广泛的研究［１］。目前，主要围绕如何提高室温电导率和机械强度进行研究［２］。在所有这些研究中，利用环氧树脂（ＥＲ）与低分子量聚乙二醇（ＰＥＧ）...     

cis－［Pt（NH_3）_2Cl_2］和trans－［Pt（NH_3）_2Cl_2］的微型合成

ｃｉｓ－［Ｐｔ（ＮＨ_３）_２Ｃｌ_２］和ｔｒａｎｓ－［Ｐｔ（ＮＨ_３）_２Ｃｌ_２］的微型合成袁书玉，来月英（清华大学化学系，北京１０００８４）ｃｉｓ－［Ｐｔ（ＮＨ２）２Ｃｌ２］为一抗癌药物，而它的反式异构体却没有这一特性。其原因也已在进行研究［１］。由...     

热对镍阳极膜光电流测定的影响

镍在碱溶液中阳极膜的形成和性质与化学电源和金属腐蚀等有关．在这方面已有较深入的研究报导．其研究方法也是多种多样,除一般的电化学方法［１,２］外,还有许多现场谱学方法,如：紫外＿可见光谱［３］,红外光谱［４］,光热光谱［５］,拉曼光谱［６］,椭圆法［７...     

离子液体和KGM修饰电极上的直接电化学

将血红蛋白固定在用室温离子液体和魔芋葡甘聚糖(KGM)水凝胶修饰的玻碳电极上,其循环伏安扫描显示一对可逆的氧化还原电流峰,克式量电位(-0.38V,vs.SCE)随溶液pH值的增大而负移,呈良好的线性关系,斜率为51 mV/pH,表明在离子液体和KGM共同修饰的电极上包埋在魔芋葡甘聚糖水凝胶中的血红蛋白发生了直接可逆的电子传递反应,并伴随有一质子的迁移过程.此外,还考察了该血红蛋白修饰电极对O2还原反应的电催化性能.     

Syntheses and Properties of Lanthanide Hydroxy-meso-tetra(p-chlorophenyl)porphyrin Complexes

Introduction The syntheses and characterization of porphyrins and metalloporphyrins have been studied extensively[1]. Hemoglobin, myoglobin or cytochrome P450, has been applied as a model compound[2]. Wong C. P. et al.[3] synthesized the first lanthanide porphyrin, acetylacetonate tetraphenylporphyrin europium, in 1974.     

Accurate mass measurement and tandem mass spectrometry of intact globin chains identify the low proportion variant hemoglobin Lepore-Boston-Washington from the blood of a heterozygote

Within a mixture of proteins, minor polymorphic components are difficult to identify using a conventional proteomic approach. Their identification generally requires multi-dimensional separation steps, before or after proteolytic cleavage, followed by sequence analysis of the proteolytic products. In this study, we investigated the potential of tandem mass spectrometry for protein characterization by identifying the delta-beta hybrid human hemoglobin variant Lepore-Boston-Washington using electrospray ionization tandem mass spectrometry. Hemoglobin Lepore-Boston-Washington occurs mainly in heterozygotes, where it comprises approximately 10% of the total non-alpha-chains, the dominant non-alpha-chain being the normal beta (approximately 90%). Furthermore, Hemoglobin Lepore-Boston-Washington has an average molecular mass (15,865.23 Da) that is only 2 Da lower than that of the normal beta-chain (15,867.24 Da). Consequently, it cannot be resolved from the normal beta-chain by mass spectrometry. Here we show how Hemoglobin Lepore-Boston-Washington was identified directly from the diluted blood of a heterozygote by analyzing the product ions from the Lepore-Boston-Washington and normal beta-chain ions without prior separation of the individual chains. This study shows the potential of the tandem mass spectrometry for identifying a minor component in an unseparated mixture of proteins.     

非有机溶剂液-固萃取体系提取血红蛋白研究

用聚乙二醇(PEG8000)修饰物混合吐温80-磷酸钾盐液-固萃取体系从血液中直接提取血红蛋白,考察了PEG8000修饰物、磷酸钾盐和吐温80的浓度及酸度和温度等因素对血红蛋白分离纯化的影响.结果表明,采用该体系的一次固相萃取率大于99%,一次反萃取率达到75%.所得到的血红蛋白干粉的纯度为99%.该方法不使用有机溶剂,无毒性,对蛋白质具有稳定和保护作用,易于放大规模使用.     

不同供氢底物用于测定H2O2的酶催化动力学研究

研究了牛血红蛋白(hemoglobin,Hb)作为过氧化物模拟酶,以酸性铬蓝K、罗丹明B、亚甲基蓝不同供氢底物测定H2O2的酶催化反应体系的催化特性和反应条件。探讨了采用不同底物测定时的催化反应机理。用于雨水中H2O2含量的测定,结果满意。     

血红蛋白在类生物膜修饰电极上的直接电化学

使用掺合单壁碳纳米管(SWCNT)的不溶性表面活性剂双十二烷基二甲基溴化铵(DDAB)修饰玻碳电极,并将血红蛋白(Hb)固定在修饰膜中制得了稳定的固载Hb的修饰电极.循环伏安和交流阻抗测试表明,固定在电极上的Hb是一个受吸附控制的可逆电子传递过程.该氧化还原过程的CV扫描峰电位与溶液pH值成良好的线性关系,斜率39 mV/pH,表明在发生Hb直接电子传递反应的同时伴随有质子参与反应.掺合SWCNT的类生物膜修饰电极较之不掺合SWCNT的修饰电极对氧气的还原具有更好的催化作用.并以SWCNT掺合量为1 mg.mL-1的DDAB修饰电极性能最佳.     

Immobilized hemoglobin in the purification of hemoglobin-based oxygen carriers.

Chemically modified hemoglobins can be used as oxygen carriers in cell-free fluids provided that they have a low oxygen affinity and are stable towards dissociation into subunits. The latter species are undesirable because they are filtered rapidly through the kidneys, have renal toxicity and are characterized by a high oxygen affinity. A most important step in the preparation of hemoglobin-based oxygen carriers is therefore their purification from any dissociable material. Hemoglobin immobilized as alpha beta dimers on Sepharose lends itself naturally to this purpose as it is able to interact in a specific and reversible way with soluble alpha beta dimers. Hemoglobin affinity columns are very effective in the purification of cross-linked and pseudo-cross-linked human and bovine hemoglobin. The applicability of the technique is enhanced by the ease with which alpha beta dimers from different species cross-interact to yield hybrid alpha 2 beta 2 tetramers. It is shown that hemoglobin affinity columns may provide analytical information on the cross-linking reaction itself.     

Characterization of hemoglobin immobilized on gamma-zirconium phosphate

The fact that different γ-zirconium phosphate (γ-ZrP) preintercalation method induced varied degree and type of conformational change of the adsorption protein was confirmed by characterization techniques including circular dichroism (CD), fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD) analysis. The results indicated that the association of hemoglobin with γ-ZrP preintercalated using butylamine was correlated with conformational change in the secondary structure of the protein. γ-ZrP which was preintercalated with tetra (n-butylammonium) hydroxide caused the conformational change of Hemoglobin in both the secondary structure and the tertiary structure. X-ray powder diffraction analysis was used to analyze the crystalline structure of the nanocomposites prepared by relamination. The adsorption isotherms of Hemoglobin on different matrices were set up and fitted with Langmuir and Freundlich equations.     

Effect of dimethyl sulfoxide on the electron transfer reactivity of hemoglobin

Hemoglobin, after being treated with dimethyl sulfoxide, exhibits a direct electrochemical response at a pyrolytic graphite electrode. The apparent standard potential (E degrees ') of hemoglobin is -0.119 V (vs. NHE). Meanwhile, since no electrochemical mediator is required for its direct electrochemistry, this work provides a convenient way to perform electrochemical research on this protein.     

血红蛋白的过氧化物酶催化特性研究

探讨了用血红蛋白（Hb)作为辣根过氧化物酶（HRP）的替代物，用于率H2O2氧 化对甲基酚的反应体系，研究了血红蛋白的过氧化物酶特征及其酶催化动力学特性 。稳态速率法测定了米氏常数（Km)、米氏速率（Vm)及反应级数等动力学参数。讨 论了对甲基酚作为血红蛋白的氢供体底物的酶催化反应机理，确立了反应速率方程 。实验比较发现血红蛋白作为过氧化物酶（HRP）的替代物，其催化活性比氯化血 红素（Hemin)，β-环糊精－氯化血红素（β－CD－Hemin)等过氧化物模拟酶要高。