新型镍离子亲和色谱介质的制备及其性能考察

以氯甲基化聚苯乙烯交联微球(氯球)为载体基质、N,N-二甲基甲酰胺(DMF)为溶剂、N,N-二异丙基乙胺(DIEA)催化,将合成的Lys(Boc)-OEt、氯乙酸乙酯连接到微球上。经水解使羧基裸露,与Ni²⁺螯合,制得新型镍离子亲和色谱介质。将其应用于His-Lys-Tyr三肽及Phe-His-Thr三肽纯化研究。以不含组氨酸的六肽作为杂质模型,用所制备的镍离子亲和介质进行分离。结果表明,所制备的镍离子亲和介质对两个含组氨酸的三肽具有很好的亲和作用,并实现了与不含组氨酸六肽的分离。     

聚电解质溶液中2.6-ANS探针的荧光谱研究

本文合成了2.6—ANS荧光探针分子,并在含有不同外加盐的NaPSS溶液中测定了探针的荧光发射光谱。结果表明:探针的荧光强度随Cs增大而增大,而探针光谱的最大发射波长和半波宽度随Cs增大而减小。当Cs达到一定值时,荧光谱参数与Cs关系曲线出现转折点,此时聚离了链以“类胶束”状态存在。     

大孔吸附树脂的合成及其对黄芩甙的吸附性能

用吸附树脂纯化分离中药黄芩中的黄苓甙是天然药物研究新技术。但吸附树脂交联聚苯乙烯疏水性强,水相与树脂之间的界面能较大,通过氯甲基化引入极性基团可以改善树脂的吸附性能。本文通过对氯甲基化后的交联聚苯乙烯(氯球)进行后交联以改善树脂孔结构,并通过胺化反应增加树脂的极性和亲水性,研究所合成一系列大孔吸附树脂的碱基含量对黄苓甙的静态吸附性能的影响。     

Pressure Effects on Thermodynamics of Phase Behavior in Polystyrene/Methylcyclohexane Solutions

The calculations presented in this paper are based on the Sanchez-Lacombe(SL)lattice fluid theory.The interaction energy parameter,g12/k,required in this approach was obtained by fitting the cloud points of polystyrene(PS)/methylcyclohexane(MCH)polymer solutions under pressure.The SL lattice fluid theory was used to calculate the spinodals,the binodals,and the Flory-Huggins(FH)interaction parameter of the solutions.The calculated results show that the SL lattice fluid theory can describe the dependences of thermodynamics of PS/MCH solutions on temperature and pressure very well.However,the calculated enthalpy and the excess volume changes indicate that the Clausius-Clapeyron equation cannot be suitable to describe pressure effect on PS/MCH solutions.Further analysis on the thermodynamics of this system under pressure shows that the role of entropy is more important than the excess volume in the present case.     

DIFFUSION OF LONG CHAINS THROUGH A POROUS THIN GEL NETWORK

Using a core(142 nm)made of linear polystyrene(PS)chains as a seed,we further polymerized a thin layer of cross-linked PS shell(7 nm)on it in water to form a core-shell particle.Such a particle swells in toluene,which enables linear PS chains inside the core to gradually diffuse out through the porous shell.Using a combination of static and dynamic laser light scattering,we examined the chain diffusion process by following the change of the scattering intensity(i.e.the average molar mass of the particles).For the first time,we have revealed that the diffusion exhibits three stages.In the first stage,the chain diffusion through the shell is even faster than their translational diffusion in a dilute solution.The three stages respectively correspond to the change of the solution in the core from concentrated to semidilute and then from semidilute to dilute.     

聚(苯乙烯-二乙烯基苯)反相高效液相色谱填料在胸腺素α1分离中的应用

采用高聚物型苯乙烯-二乙烯基苯(PS-DVB)麦科菲反相高效液相色谱柱(MKF-RP-MH)分离胸腺素α1,优化色谱条件为:流动相A:0.01 mol/L磷酸盐缓冲液(pH 7.0或8.0),流动相B:乙腈,梯度洗脱条件0~20 min,0%~10%乙腈,20~40 min,10%~30%乙腈;温度:30℃;流速:0.8 mL/min;检测波长:214 nm。在优化条件下分离了胸腺素α1标准品和样品。样品浓度在0.05~4 g/L时,线性方程为C=0.0099A-0.0798(r=0.9994),胸腺素α1最大载样量为120μg(6 g/L)。     

聚四氢呋喃/聚苯乙烯交联嵌段及接枝共聚物的合成与阻尼性能

Carboxyl vinyl terminated polytetrahydrofuran macromers and telechelic oligomers were synthesized from hydroxyl terminated polytetrahydrofuran by end group conversion. From these macromers or telechelic oligomers and styrene polytetrahydrofuran/polystyrene segmented and graft copolymers were synthesized and the effects of molecular structure on the damping properties of those copolymers were also studied.     

星形支化聚苯乙烯模型化合物的合成及表征

本文用阴离子聚合方法,首先合成了线形‘活’的聚苯乙烯大分子阴离子,然后用二乙烯基苯为偶联成核剂,制备了十三个4-80臂较窄分子量分布的等臂长规则星形支化聚苯乙烯的模型化合物,并用GPC—粘度计联用装置对之进行了表征。     

交联聚苯乙烯吸附树脂的修饰及其对天然皂甙的吸附性能

交联聚苯乙烯氯甲基化后,将氯转化为羟基、氨基、甲氧基、苯氧基、4-羟基苯氧基和4-乙酰苯氧基,合成了不同极性的吸附树脂Ⅰ—Ⅵ。同时由交联聚苯乙烯经Friedel-Crafts酰化反应在其苯环上引入乙酰基,制备了树指Ⅶ。用物理技术和化学方法表征树脂Ⅰ—Ⅶ的结构,然后测定了它们对天然皂甙如甜菊甙和绞股蓝皂甙的吸附量。结果说明,这些树脂亲水性较好,均能吸附天然皂甙,但只有中极性的酮基树脂Ⅵ和Ⅶ的吸附量较大。     

改进的种子聚合——单分散交联聚苯乙烯微球的合成

本文结合了种子聚合法和二步溶胀法的特点,提出用改进的种子聚合法以合成粒径大于3微米、粒度呈单分散的交联聚苯乙烯微球。文中采用的粒径为1—2微米的聚苯乙烯胶乳种子是由无皂乳液聚合法制备的。文章研究了溶胀温度、溶胀剂比例、溶胀时间、交联剂、小分子化合物及表面活性剂等因素对生成微球的粒径和分散性的影响。