不同反相色谱系统保留值方程系数的换算

在统计热力学基础之上，运用数学方法导出了不同反相色谱系统中保留值方程系数换算公式如下：ａ′＝ｋ１＋ｋ２ａ＋ｋ３ｘＡ氢ｃ′＝ｊ１＋ｊ２ｃ＋ｊ３ｘＡ氢采用正构烷烃、卤代苯、烷基苯、氯代酚等类型化合物的实验数据，验证了上述公式。本文为不同反相色谱体系保留值的换算奠定了基础。     

色谱优化法的研究及其在药代动力学中的应用

本文研究了弱碱化合物保留值方程（ｌｎｋ＝ａ＋ｃＣｂ－ｌｎ（１＋１０１４Ｋｂ［Ｈ＋］）），根据色谱动力学和色谱热力学原理编辑了相应软件，应用该软件优化出奥美拉唑及其代谢物和内标物的高效液相色谱分离条件，完成了奥美拉唑正常人体内药代动力学研究     

反相高效液相色谱法对八种吡嗪类化合物保留性能的研究

在Ｓｐｈｅｒｉｓｏｒｂ－Ｃ（１８）反相柱上,以甲醇－水为流动相,对八种吡嗪类化合物的保留性能进行了考察。同时用不同浓度下的冲洗剂所得保留值和关系式ｌｎｋ＇＝ａ＋ｃＣｂ中的参数ａ、ｃ作线性关系,得到很好的相关性。流动相中不同的无机盐及微量有机胺类改性剂的加入,可有效地改进分离。当甲醇：０．２ｍｌ／ＬＨＡｃ－ＮａＡｃ缓冲液（ｐＨ４．５）：三乙胺为４０：５９：１（Ｖ／Ｖ）时,除两种同分异构体不能分离外,所有组分在２５ｍｉｎ内可实现较理想的分离。     

氰尿酸钡的晶体结构

报道了氰尿酸钡［Ｂａ（Ｃ_３Ｈ_２Ｎ_３Ｏ_３）_２·（Ｈ_２Ｏ）_２］的晶体结构。晶体属三斜晶系，空间群为Ｐ１，晶胞参数为：ａ＝８．８８４（３）．ｂ＝９．４２２（４），ｃ＝７．２０１（４）Ａ，α＝９７．７５（４），β＝１０１．７６（４），γ＝８５．０５（３）°；Ｍ_ｒ＝４２９．４９，Ｚ＝２，Ｄ_ｃ＝２．４４ｇ／ｃｍ~３。Ｖ＝５８３．６（４）Ａ~３，μ＝３４．５６ｃｍ~（－１），λ（ＭｏＫα）＝０．７１０６９Ａ，Ｆ（０００）＝４１２，Ｉ＞３σ（Ｉ）的衍射点２０９１个。结构用ＴＥＸＳＡＮ程序包以直接法解出，经全距阵最小二乘法修正，最后Ｒ因子为０．０２９，Ｒ_ω＝０．０３７．中心离子Ｂａ~（２＋）的配位数为１０，Ｂａ~（２＋）离子处于６个配位原子形成的平面的中心位置上，另外４个配位原子则处于平面外，分布在Ｂａ~（２＋）离子的周围。     

反相高效液相色谱对8种噻唑类衍生物保留性能的研究

在ＯＤＳ反相柱上，考察了不同浓度下的甲醇／水对８种噻唑衍生物保留值的影响。并把不同浓度的冲洗剂所得保留值和关系式ｌｎＫ′＝ａ＋ｃＣｂ中的参数ａ、ｃ作线性关联，得到很好的相关性，同时考察了不同种类的无机盐和有机胺对噻唑类衍生物容量因子ｋ′的影响。     

B链羧端去三肽(B28～B30)胰岛素晶体结构

采用悬滴气相扩散法，获得了Ｂ链羧端去三肽胰岛素３种晶型的单晶体，其中 晶型１属于Ｐ２_1空间群，晶胞参数为ａ＝４．７７ ｎｍ，ｂ＝６．１９ ｎｍ，ｃ＝６．１２ ｎｍ，β＝１１０．３°；晶 型２属于Ｐ４_１２２或Ｐ４_３２２空间群，晶胞参数为ａ＝ ６．４５ ｎｍ， ｃ＝ １２．０７ ｎｍ；晶型３属于 Ｐ２_１２_１２_１空间群，晶胞参数为 ａ＝ ４．９８ ｎｍ， ｂ＝ ５．１６ ｎｍ， ｃ＝ １０．０６ ｎｍ．采用分子置换法， 测定并精化了 Ｂ链羧端去三肽胰岛素晶型１的 ０．２３ ｎｍ分辨率晶体结构．最终模型的 Ｒ 因子为１８．８％，键长和键角与标准键长和键角的均方根偏差分别为０．００１５ ｎｍ和３．３°． 晶体结构的结果表明， Ｂ链羧瑞去三肽胰岛素失去了对缔合有重要作用的 Ｂ２８ Ｐｒｏ后， 虽然仍能形成六聚体，但表现出比天然胰岛素更易解聚的结构变化。     

镨、钕、钇、甘氨酸三元配合物的晶体结构

在水溶液中培养了镨、钕、钇与甘氨酸形成的三元配合物。元素分析和热分析表明，该配合物可用Ｐｒ_ｘＮｄ_ｙＹ_ｚ（Ｇｌｙ）_６（Ｈ_２Ｏ）_４（ＣｌＯ_４）_６·５Ｈ_２Ｏ（Ｘ＋ｙ＋ｚ＝２）表示其分子式。Ｘ射线衍射方法测定了其单晶结构，结果表明，该晶体属三斜晶系，空间群Ｐ１，化学式Ｐｒ_（０．７７５）Ｎｄ_（０．７００）Ｙ_（０．５２５）Ｃｌ_６Ｏ_（４５）Ｎ_６Ｃ_（１２）Ｈ_（４８），Ｍ_ｒ＝１４６６．０９，晶胞参数如下：ａ＝１１．５６４（１），ｂ＝１４．１１８（３），ｃ＝１５．６６８（２）Ａ，α＝９６．９９（１），β＝１０２．７２（１），γ＝１０５．３３（１）°，晶胞体积Ｖ＝２３６２（１）Ａ~３，Ｚ＝２，Ｄ_ｃ＝２．０６０ｇ／ｃｍ~３，结构偏离因子Ｒ＝０．０３２，Ｒ_ｗ＝０．０４８。晶胞中存在两个络合单元，每个单元可用Ｍ_１Ｍ２（Ｇｌｙ）_６（ＣｌＯ_４）_６（Ｈ_２Ｏ）_４．５Ｈ_２Ｏ表示，Ｍ_１＝０．４Ｐｒ＋０．３７５Ｎｄ＋０．２２５Ｙ，Ｍ２＝０．３７５Ｐｒ＋０．３２５Ｎｄ＋０．３０Ｙ。三种稀土元素按一定比例统计性地占有两个格位。羧基以桥式联结金属离子，形成一维链式聚合物结构。在络合单元中，一个稀土离子是９配位，其配位多面体为畸变?     

α—羰基烯酮环二硫代缩醛化学：XXI：β,β—1,3—亚丙二硫基—α,β—不饱和酮？

在乙醇为溶剂，乙醇钠为碱的条件下，标题类化合物１ａ～ｃ，３ａ，４ａ与胍缩合反应生成相应的嘧啶类化合物２ａ～ｃ，３ｂ，３ｃ，４ｂ。在以ＤＭＦ为溶剂，乙醇钠为碱的条件下，化合物１ａ与胍反应可生成２－氨基－４－二甲氨基－６－苯基嘧啶２ａ，该缩反应的特点为标题类化合物与胍缩合生成嘧啶类化合物的同时，将乙氧基或二甲氨基引入嘧啶环的确定位置，２ａ，２ａ，３ｂ，３ｃ，４ｂ为新的嘧啶在化合物。     

单元练习九参考答案

单元练习九参考答案一、二、已造挥回３０．①当酸不足量ｂ＜ａ＋ＣＡｌ（Ｏ）。１５６ｂ克）当酸过量ｂ＞％Ｍ（ｏＨ儿Ｏ克③当酸在①②之间／／’２＜ｂ＜３１．①０．２９６克①０、２１２克３２、１２０亿吨３３．１．８２？４五、Ｎ,原来为ＫＩ计算略）３５．６克’...     

金属离子与卟啉的嵌入反应动力学研究──Ⅶ．一元酸根催化Cu（Ⅱ）与溴化间－四（N－乙酸甲酯基－3－吡啶基）卟啉的配位反应

研究了在３５±０．１℃、离子强度０．５ｍｏｌ／Ｌ（ＫＣｌ）条件下，甲酸根、乙酸根、丙酸根和丁酸根分别催化Ｃｕ（Ⅱ）离子与四溴化间－四（Ｎ－乙酸甲酯基－３－吡啶基）卟啉（Ｈ２ＴＢ－Ｎ－ＡＣＭＳｐｙＰＢｒ４）的反应动力学及其机理，该类反应对卟啉和Ｃｕ（Ⅱ）离子均为一级反应，反应动力学方程为：ｄ［Ｃｕｐ４＋］／ｄｔ＝ｋ｛（１．０＋ｂ［Ａ－］）／（１．０＋Ｋ３，４·［Ｈ＋］２）｝［Ｃｕ２＋］［ｐ］Ｔ，在甲酸－甲酸根缓冲体系中，ｋ＝２．９８ｍｏｌ－１ｄｍ３·ｓｅｃ－１，ｂ＝１５４×１０２ｍｏｌ－２，ｄｍ６·ｓｅｃ－１，Ｋ３，４＝６．９２８×１０３；在乙酸－乙酸根缓冲体系中，ｋ＝３．４２ｍｏｌ－１·ｄｍ３·ｓｅｃ－１，ｂ＝２．２９×１０３ｍｏｌ－２·ｄｍ６·ｓｅｃ－１，Ｋ３，４＝６．９２８×１０３；在丙酸－丙酸根缓冲体系中，ｋ＝３．００ｍｏｌ－１·ｄｍ３·ｓｅｃ－１，ｂ＝５．９０×１０２ｍｏｌ－２·ｄｍ６·ｓｅｃ－１，Ｋ３，４＝７．００７×１０３；在丁酸－丁酸根缓冲体系中，ｋ＝３．１４ｍｏｌ－１·ｄｍ３·ｓｅｃ－１，ｂ＝３．７５×１０２ｍｏｌ－２·ｄｍ６·ｓｅｃ－１，Ｋ３，４＝６．９２１×１０３；讨论了有机酸根的碱性与     

Thin-Layer Chromatography of Bile Alcohols,Bile Acids and Conjugated Bile Acids

Abstract

Thin-layer chromatography of bile alcohols, bile acids and bile acid conjugates has been reviewed. Particular emphasis has been placed on the separation of the glycine and taurine conjugated bile acids as a class and as individual compounds, and on the isolation of bile alcohols and C₂₇ bile acids diastereo-isomeric at C-25.     

Separation and Determination of Bile Acids in Human Bile by High-Performance Liquid Chromatography

Abstract

A method for simultaneous determination of major bile acids in human bile is described. The unconjugated, glycine- and taurine-conjugated bile acids are extracted with Sep-pak C¹⁸ and separated into groups by ion-exchange chromatography on a lipophilic gel. Subsequently, resolution of each group into ursodeoxycholate, cholate, chenodeoxycholate, deoxycholate and lithocholate is attained into two stages by high-performance liquid chromatography on a Radial-PAK A column. First, 0.3% ammonium phosphate (pH 7.7)/acetonitrile (19:8, v/v) is used for separation of the latter three as a mobile phase. Ursodeoxycholate and cholate are efficiently separated in 0.3% ammonium phosphate (pH 7.7)/acetonitrile (23:8, v/v). The present method is applicable to quantitation of bile acids in human bile with satisfactory accuracy and precision.     

Specificity and Cross Reactivity in Bile Acid Radioimmunoassays Serum Bile Acids,Radioimmunoassay

Abstract

In man there are four main bile acid fractions and within each fraction there is the possibility of at least three bile acid moities - two conjugated and one unconjugated. Bile acids thus present a considerable challenge to radioimmunoassay techniques. Few of the antisera described to date are satisfactory in that they do not show equal reactivity to each of the moities to be assayed, and many have unacceptable cross reactivity properties. Clearly there is need for caution and development in this field. The first application of radioimmunoassay (RIA) techniques to the measurement of serum bile acids was made by Simmonds, Korman, Go and Hofmann in 1973¹. Because of its unique sensitivity and ease of application, RIA has been used not only to determine the increased serum bile acid levels found in liver disease, but also to monitor the clearance of bile acids from the peripheral circulation of normal subjects, to provide 24 hour serum bile acid profiles in normal subjects and even to assay the low serum bile acid levels found in patients in whom the bile acid enterohepatic circulation has been interrupted. Some 20 preparations of bile acid antisera have been described to date and commercial kits are now available, for RIA of each of the 4 major bile acid fractions found in human sera. Considerable differences however, in the specificity of these antisera are indicated by their reported cross reactivities and the analytical validity of their use is often questionable.     

超高效液相色谱快速分析不同哺乳动物胆汁中胆汁酸

建立超高效液相色谱同时快速测定胆汁中13种胆汁酸浓度的方法,并对种内种间差异进行统计学分析.色谱柱为Kyoto C18(100 mm×2.1 mm,2.2 μm);流动相为乙腈-10 mmol/L KH2PO4溶液,梯度洗脱;流速:0.5 mL/min;检测波长200 nm.各种胆汁酸在各自测定浓度范围内与峰面积的线性关系良好(r＞0.9995);所有胆汁酸能够达到良好分离.13种胆汁酸检出限(S/N=3)在0.2～0.6 ng/μL之间.与传统HPLC法相比,本方法简便、快速,精密度高,重现性好,适用于胆汁酸的分析.     

反相高效液相色谱法测定鼠胆汁中游离与结合型胆汁酸

建立了一种柱前衍生反相高效液相色谱荧光检测大鼠胆汁中游离与结合型胆汁酸的方法.以4-溴甲基-7-甲氧基香豆素为衍生剂,月桂酸为內标,Waters Nova C18色谱柱分离,采用甲醇/乙腈和水梯度洗脱,荧光激发波长(λex)330 nm,发射波长(λem)400 nm,內标标准曲线法定量.各胆汁酸在5-2 400μmol/L范围内线性良好,r为0.998 9-0.999 7.最低检出限为1.2-2.5μmol/L.精密度日内在1.05%-3.67%之间,日间在3.16%-6.83%之间.平均回收率为87.8%-106.7%.该方法灵敏、重复性好,分析时间短,线性范围宽,适合于科研工作中对鼠胆汁中各胆汁酸进行定量检测.     

Bile salt-phospholipid aggregation at submicellar concentrations

The aggregation behavior of the bile salts taurodeoxycholate (NaTDC) and sodium cholate (NaC), are followed at concentrations below critical micelle concentrations (CMCs) using the environment sensitive, fluorescent-labeled phospholipid, 2-(6-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl-1-hexadecanoyl-sn-glycero-3-phosphocholine (NBD-C₆-HPC). A buffer solution containing NBD-C₆-HPC is titrated with increasing NaC or NaTDC and the fluorescence changes followed. Both bile salts induced fluorescence changes below their critical micelle concentration indicating the presence of a bile salt–phospholipid aggregate. A critical control experiment using 6-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino) hexanoic acid (NBD-X) shows that the bile salts are interacting with the longer, C16 hydrocarbon tail, not the NBD probe. The fluorescence curves were fitted to the Hill equation as a model for cooperative aggregation. The cooperativity model provides a minimum estimate for the number of bile salts to give maximal fluorescence. This number was calculated for NaC and NaTDC to have a minimum value of 2. A small aggregation number supports the existence of primary micellar aggregates at submicellar concentrations for bile salt–phospholipid aqueous solutions.     

基于胆汁酸的刺激响应聚合物

刺激响应聚合物是当今材料科学研究的热点之一。其在外界刺激下,自身的物理或者化学性质发生变化产生响应,在药物可控释放、生物传感器、催化、吸附分离等方面有广阔的应用。胆汁酸是天然的甾类生物分子,其分子结构中含有羟基和羧基等官能团,容易进行化学修饰,且具有双亲性和一定的刚性。在聚合物中引入胆汁酸分子,能够从结构和功能两个方面丰富刺激响应高分子的研究。一方面,胆汁酸及修饰的胆汁酸既可以作为单体直接聚合,也可以被连接到含有一定官能团的聚合物上,由此可以得到以胆汁酸作为主链、侧基、端基,以及胆汁酸作为星形聚合物的核等多种聚合物结构。另一方面,胆汁酸的引入不仅可以提高聚合物的生物相容性,有效地赋予聚合物胆汁酸结构的独特性质,而且可以用于构建具有一定刺激响应功能的组装结构,进而应用于形状记忆、手性分离、药物载体等材料中。本文综述了基于胆汁酸的刺激响应聚合物近年来的相关工作,从基于胆汁酸的刺激响应聚合物的分子设计和结构构筑出发,结合其性质和应用进行论述,也对该领域的改进和发展提出展望。     

Bile Acids-Selective Chemosensors Based on NBD-amine-Modified Cyclodextrins

A new type of fluorescent chemosensor, based on modified cyclodextrins bearing the fluorophore unit NBD-amine, was prepared. One of these new chemosensors, NC0γCD is very sensitive to bile acids, but is not sensitive to other guests (e.g. adamantane and borneol derivatives). The response of the new type of chemosensor to a guest was an increase in the fluorescence intensity and the sensitivity parameter (ΔI/I ₀ ) dose not correlate to the binding affinity of NC0γCD.     

胆酸衍生物的合成及其应用

综述了胆酸衍生物,包括应用于高分子材料、分子识别及医药领域的胆酸衍生物的合成.