磷脂酰胆碱胶团化热力学函数及胶团聚集数的研究

磷脂酰胆碱胶团化热力学函数及胶团聚集数的研究陈鲁生周武姜云生（山东师范大学化学系济南２５００１４）关键词磷脂酰胆碱临界胶团浓度热力学函数聚集数中图分类号Ｏ６４２．１１磷脂酰胆碱是广泛存在于生物体内的一种天然两性表面活性剂，在生物体内起代谢作用和结构形...     

二亚油酰磷脂酰胆碱分析

通过HPLC/HPLC-MS研究了二亚油酰磷脂酰胆碱的测定方法,磷脂样品首先经过HPLC分离得到磷脂酰胆碱,该磷脂酰胆碱再进一步通过不同的HPLC系统分离二亚油酰磷脂酰胆碱,并通过标准样品和质谱进行二亚油酰磷脂酰胆碱的定性.定量方法通过标准样品外标法定量,由方法的回收率和精密度试验可知,该方法已用来测定一般磷脂样品和磷脂酰胆碱样品中的二亚油酰磷脂酰胆碱含量.     

Wilhelmy吊片法测定磷脂溶液的表面张力等温线

表面活性物质的表面张力等温线测定是大学物理化学实验的重要内容。随着磷脂类表面活性剂的广泛应用，有必要在大学化学中更新经典表面张力等温线测定的实验内容，并使学生掌握先进的测量方法。以二硬脂酰基磷脂酰胆碱(DSPC)和二棕榈酰基磷脂酰胆碱(DPPC)为研究对象，应用界面张力仪测定了两种溶液表面张力等温线，计算了其表面超量和分子横截面积，并设计了拓展性实验内容，对于培养学生分析问题和解决问题的能力具有积极的意义。     

高效液相色谱法分析大豆中磷脂酰胆碱的分子种

用高效液相色谱法（HPLC）在正相半制备硅胶柱上将大豆磷脂酰胆碱与其它组分分离，从柱后收集磷脂酰胆碱（PC），然后在反相C18柱上分析其分子种组成，蒸发光散射检测器检测。在25min内将大豆磷脂酰胆碱分离成11个分子种组分，使用易挥发溶剂，可获得各种分子种的纯物质，供进一步分析。分子种根据HPLC峰的脂肪酸组成分析而确定。     

制备磷脂酰胆碱衍生物的改进方法

制备磷脂酰胆碱衍生物的改进方法贾春华Ａ．Ｈ．Ｈａｉｎｅｓ（南京林业大学，南京２１００３７）（ＴｈｅＵｎｉｖｅｒｓｉｔｙｏｆＥａｓｔＡｎｇｌｉａ，Ｕ．Ｋ．）磷脂酰胆碱是细胞膜的主要成分之一，人们对磷脂酰胆碱的结构类似物在可能治疗爱滋病方面有较大的兴趣。...     

改性苯乙烯-马来酸酐共聚物色谱固定相用于磷脂分离分析北大核心CSCD

磷脂是重要的信号分子,磷脂的代谢与多种疾病密切相关。因此,开展磷脂的分离分析研究至关重要。苯乙烯-马来酸酐共聚物(SMA)作为一种新型两亲性交替共聚物可以插入生物膜的磷脂双分子层中,形成以膜蛋白质为中心的脂质纳米盘,对膜蛋白质和磷脂具有良好的增溶作用。本文基于“点击”反应和自由基聚合反应,将对磷脂具有良好增溶性能的SMA接枝到硅胶表面,然后以蛋氨酸甲酯盐酸盐(MME·HCl)为开环试剂,通过亲核开环反应对SMA进行修饰,制备了新型的改性SMA修饰色谱固定相(Sil-SMA-MME)。结合高效液相色谱-紫外检测法,利用酰胺类和核苷/核酸碱基类以及苯酚类3类小分子物质对填充Sil-SMA-MME色谱柱的保留机制和分离性能进行了系统评价,Sil-SMA-MME色谱柱具有典型的亲水作用保留机制,其柱效最高可达90900 N/m,并显示了良好的分离选择性。进一步结合高效液相色谱-蒸发光散射检测法,考察了Sil-SMA-MME色谱柱对磷脂样品的分离性能。二棕榈酰磷脂酰丝氨酸钠(DPPS)、二油酰磷脂酰胆碱(DOPC)、二棕榈酰磷脂酰乙醇胺(DPPE)和4种磷脂酰胆碱(PC)类标准品溶血卵磷脂(LysoPC)、二肉豆蔻酰磷脂酰胆碱(DMPC)、二硬脂酰磷脂酰胆碱(DSPC)、二棕榈酰磷脂酰胆碱(DPPC)均可实现基线分离,并且成功地实现了南极磷虾油和人血清磷脂提取物的分离分析。以上结果表明,所制备的Sil-SMA-MME色谱柱在磷脂类物质分离分析中具有良好的应用潜力。     

含芳基磷脂酰胆碱类似物的合成

磷胆酰胆碱;磷脂类似物;酰化;含芳基磷脂酰胆碱类似物的合成     

基于鸟枪法脂质组学研究环氧酶-2抑制剂对关节炎模型血清脂代谢的干预作用

心血管疾病(CVD)是类风湿关节炎(RA)患者死亡的重要原因之一,脂代谢紊乱与CVD发生有密切关联,因而有必要对RA和药物治疗导致的脂代谢改变进行探讨。该研究采用胶原诱导法(CIA)构建关节炎模型,引入多维质谱鸟枪法开展血清脂质分析,检测了血清中105种脂质分子,发现模型大鼠体内7种磷脂酰肌醇、15种鞘磷脂、5种神经酰胺、10种磷脂酰胆碱和2种溶血磷脂酰胆碱异常上调,环氧酶-2(COX-2)抑制剂可部分修复紊乱的脂代谢,但对5种磷脂酰胆碱和1种溶血磷脂酰胆碱具有异常调控作用。该研究从脂质分子水平探讨了RA及COX-2抑制剂对脂代谢的干预作用,可以为RA的心血管风险研究提供信息。     

台风过后网箱养殖大黄鱼恢复过程中血清代谢物变化的研究

为了考察台风影响后鱼类恢复过程中血清代谢物的变化,利用超高效液相色谱-四极杆-飞行时间质谱,电喷雾电离源分别在正负离子模式下,对超强台风"罗莎"影响后的象山港网箱养殖大黄鱼血清进行为期半个月的测定,并通过SIMCA-P软件进行主成分分析和正交偏最小二乘法辨别分析.结果表明,大黄鱼恢复过程中潜在生物标志物主要为磷脂酰胆碱和溶血磷脂酰胆碱.另外还有皮五醇和牛黄胆酸.其中,溶血磷脂酰胆碱、含高不饱和度脂肪酰基的磷脂酰胆碱(总不饱和度之和大于9)和牛黄胆酸在恢复过程中均呈现增加的趋势; 而含低不饱和度脂肪酰基的磷脂酰胆碱(总不饱和度之和小于8)和皮五醇则呈现减少的趋势.这些代谢指标物的变化,体现了大黄鱼在台风后恢复过程中,通过皮质类激素调节脂类物质代谢的结果.     

傅里叶变换红外光谱法分析乳制品的成分

利用甲醇沉淀进口奶粉、国产奶粉和奶茶粉水溶液中的蛋白质,所得上清液用二氯甲烷萃取,再经傅里叶变换红外光谱法(FT-IR)分析沉淀物和各相中物质的成分.试验结果表明:3种样品沉淀物中均含有蛋白质和脂肪酸甘油三酯,在萃取时均有乳糖析出.三者上层(水+甲醇)均含有糊精;而下层(二氯甲烷-甲醇)进口奶粉中含有磷脂酰胆碱,国产奶粉中含有磷脂酰胆碱和长碳链伯酰胺,奶茶粉中含有咖啡因.     

羧甲基纤维素钠和甲基纤维素在ZrO_2微粉上的吸附作用及其对悬浮体稳定性的影响

研究了ZrO2微粉自水中对羧甲基纤维素钠（CMC）和甲基纤维素（MC）的吸附作用及对ZrO2水悬浮作稳定性的影响．结果表明：（1）CMC的吸附等温线为Langmuir型,CMC可能以较为舒展的方式单层吸附于ZrO2。表面,由于有电性吸引作用在pH3．4时的极限吸附量较pH7．0时的略大;（2）MC的极限吸附量远大于CMC的,MC分子可能以线团状吸附,吸附层厚度可达14～56nm;（3）难较大浓度时MC比CMC更易于使ZrO2悬浮作稳定．     

羧甲基纤维素取代均一性的研究

羧基纤维素(钠盐,以下简称CMC)是一种重要的水溶性聚电解质。本文在传统溶媒法的基础上,采用乙醇作溶剂的两段加碱法新工艺制备CMC。研究表明,在低浴比(乙醇与纤维素质量比为2.04～2.45)条件下,采用新工艺制得的CMC具有较好的取代均一性和良好的性能:并用酶降解的方法,通过还原值测定,对CMC的取代基沿分子链的分布进行了表征;此外,对CMC的一些性能进行了测定,同时对其热稳定性进行了研究。     

STUDY ON THE CHARACTERIZATION OF DISTRIBUTION OF SUBSTITUENTS ALONG THE CHAINOF CARBOXYMETHYL CELLULOSE

Four new paranmeters, and , and have been proposed to describe the average length of the sequence of substituted anhydroglucose units and that of unsubstituted ones respectively along the CMC chain. The methods for determining those parameters have also been presented . Six CMC samples have been characterized in terms of intrinsic viscosity, degree of substitution (DS), index of substitution(SI)_ and . It has been proved experimentally that, not only can describe the sequence distribution along the CMC chain, but also can be used for calculating SI and estimating the average degree of substitution in the substituted glucose rings.     

羧甲基纤维素系列高分子表面活性剂的嵌段结构对其形态和性能的影响

采用超声波辐照聚合的羧甲基纤维素 (CMC)系列高分子表面活性剂是由CMC嵌段和含有等长双亲性支链的嵌段构成的共聚物 ,研究结果表明 ,CMC链段保证了共聚物的增粘性能 ,双亲性嵌段提供了共聚物优良的表面活性 ;CMC增粘嵌段与表面活性嵌段作为共聚物的两个嵌段 ,各发挥其作用 ,得到既有增粘性能又有高表面活性的双亲性共聚物 .     

FLUORESCENCE PROBE STUDIES ON THE SECOND CRITICAL MICELLE CONCENTRATION OF SEVERAL KINDS OF SURFACTANTS

The fluorescence intenstiy ratios (F₂/F₁) of excimer (F₂) to monomer (F₁) of probe (pyrene) were measured as a function of the concentration of the surfactant in several systems, which consist of sodium hexadecyl sulfonate (C₁₆As)-anionic surfactant, cetyltrimethylammonium bromide (CTAB)-cationic surfactant and pentaoxyethylene decyl ether (C₁₀E₅)-nonionic surfactant. The second CMC values were obtained according to F₂/F₁ ~ surfactant concentration curve break. In addition, we also studied the variation of second CMC vs NaCl concentration. It was found that the second CMC values of C₁₆A₅ and CTAB decreased with the increase of NaCl concentration. But the present of NaCl had no influence on the second CMC value of C₁₀E₅. Results showed that sphere-shaped micelles turn into rod-like micelle at the second CMC. The results were interpreted in terms of diffusion of pyrene molecules and the distribution of pyrene among micelles.     

聚氧乙烯-聚氧丙烯嵌段共聚物在水溶液中的胶束化作用

本实验采用表面张力法,苯红紫可见光吸收法测定L64,AE32,AP221等三种不同结构的聚氧乙烯-聚氧丙烯嵌段共聚物的临界胶束形成浓度CMC,发现L64与AE32在低浓度下形成单分子胶束,在高浓度下形成聚集胶束。AP221则只在较低的浓度下形成聚集胶束。不同温度下CMC的测定结果表明温度对L64形成单分子胶束的CMC影响较小,而聚集胶束的浓度则随着温度升高而迅速下降,后者胶束形成热ΔH较高,为140.6kJ/mol。     

BEHAVIOUR OF MICELLES OF A NON-IONIC SURFACTANT IN THE PRESENCE OF CONCENTRATED ELECTROLYTES AT DIFFERENT TEMPERATURES

Micelle formation of nonylphenol polypropylene polyethylene oxide (NPE-1800) was investigated in aqueous and aqueous electrolyte solutions. The study focused on the effect of temperatures, 25, 30, 35 and 40°C and on the effect of concentrated inorganic electrolytes, NaNO₃, KCI, KNO₃, K₂SO₄ and MgCl₂.6H₂O. The Critical Micelle Concentration (CMC) was determined by surface tension measurements. On the basis of the actual CMC and its temperature dependence, the thermodynamic functions of micelle formation (δH°, δS°, δG°) were calculated.

According to the experimental results, the CMC at high electrolyte concentration increases with increasing temperature. This behaviour is attributed to the salting-in mechanism.

Viscometry supports the behaviour of NPE-1800 in concentrated electrolytes and the decrease of (η is attributed to the decrease of the solvency of the electrolytic solution.     

VARIATION OF STERN-VOLMER QUENCHING CONSTANTS IN MICELLAR SOLUTION AS A FUNCTION OF AQUEOUS OR MICELLAR QUENCHER

Abstract— The critical micelle concentration (CMC) of a fluorescent detergent may be measured by determining Stern-Volmer quenching parameters as a function of detergent concentration. The CMC's of a cationic detergent, 11-(3-hexyl-l-indolyI)undecyltrimethylamrnoniurn bromide (6-In-ll+), and an anionic detergent, sodium H-(3-hexyI-l-indoiyI) undecyl sulfate (6-In-ll⁻) were determined by this quenching procedure. Quenchers which were predominantly located in the aqueous phase (e.g. Co²+) or in the micellar phase (e.g. benzophenone) were employed. Aqueous phase quenchers are more effective below the CMC and cause a decrease in the long wavelength portion of the fluorescence band of the indole moiety. Quenchers located in the micellar phase are more effective above the CMC and decrease the short wavelength portion of the fluorescence band of the system.     

THE UNIFORMITY OF DISTRIBUTION OF SUBSTITUENTS ALONG THE CHAIN OF CARBOXYMETHYL CELLULOSE SYNTHESIZED IN TWO-PHASE MEDIUM C6H66——C2H5OH

 Based on the property that carboxymethylcellulose (CMC ) can be de-graded to anhydroglucose residues by cellulase, the rate constant (K) of enzymatic degra-dation of CMC synthesized in the benzene-ethanol medium has been determined. Further-morel experimental equation K = 2.71× 10^-2(DS)^-1.2 reflecting the relationship betweenK and the degree of substitution (DS) is correlated and used to describe chemical mi-crostructure uniformity of the distribution of substituents along chains effectively. Chain structure parameters of enzymatic degradation products of CMC — the number of chain breaks and the percentage of glucose released have been also measured.Average length of substituted and unsubstituted chain segments are calculated simultaneously.Through the study of static and dynamic procedures of enzymatic degradation,the method to characterize the distribution of substituents of CMC along the chain has been improved.     

稳态荧光探针研究支链烷基苯磺酸钠的聚集行为

以芘为荧光探针、二苯酮为猝灭剂,用稳态荧光探针法测定了合成的4种带干扰基(磺酸基邻位的短链烷基)的支链烷基苯磺酸钠的临界胶团浓度、合适猝灭剂浓度下的胶团聚集数以及在不同浓度氯化钠水溶液中的胶团聚集数.结果表明,支链烷基苯磺酸钠分子中长链烷基碳数增加,临界胶团浓度大幅度降低,胶团聚集数减小;分子中短链烷基碳数增加,临界胶团浓度降低幅度小,胶团聚集数增大;胶团聚集数随氯化钠浓度增大而增大.