开管毛细管亲和液相色谱初探

 提出了一种新的亲和色谱模式开管毛细管亲和液相色谱。在内径为 5 0 μm的毛细管内表面键合一层三嗪染料配体 ,利用毛细管电泳仪的压力系统进行亲和色谱实验。采用流动相切换洗脱技术 ,牛血清白蛋白和溶菌酶获得了有效的分离。连续运行 10次 ,溶菌酶的出峰时间、峰面积和峰高的相对标准偏差分别为0 1% ,4 3% ,3 7%。在 8 6ng～ 2 8 7ng范围内 ,溶菌酶的进样量与峰面积和峰高都呈线性关系 ,其相关系数分别为 0 9946和 0 9988。     

毛细管电泳法检测随机尿中香草扁桃酸和肌酐含量

采用毛细管区带电泳(CZE)对随机尿中香草扁桃酸(Vanillylmandelic Acid,VMA)、肌酐(Creatinine,CR)进行测定.实验优化了缓冲介质、分离电压、毛细管内径等参数.结果表明:在优化条件下,VMA和CR在13 min内可以实现分离检测,VMA和CR分别在0～500 μmol/L和0～4 0...     

赖氨酸的毛细管电泳特性及测定

研究了缓冲液pH和操作温度对赖氨酸毛细管区带电泳分离中运行电流、电渗迁移率、峰形等参数的影响,确定了赖氨酸电泳分离的最佳实验条件,建立了毛细管区带电泳测定赖氨酸的方法。线性范围为0．1－3．0g/L,检出限为0．03g/L。该法操作简便迅速,重复性好。用于赖氨酸发酵液中赖氨酸的含量测定,结果令人满意。     

高效毛细管电泳检测克莱保健烟贴中的尼古丁

1　引　　言尼古丁是一种生物碱。尼古丁的检测方法有薄层色谱法、容量法、电导滴定法等。本文研究了用毛细管电泳技术分离测定克莱保健烟贴中的尼古丁 ,获得了比较满意的结果。2　实验部分2 1　仪器与试剂　 12 2 9型高效毛细管电泳仪 (北京新技术应用研究所 ) ,固定波长紫外检测器 ,ＡＣＳ2 0 0 0高压电源 ,ＡＣＳ2 0 0 0色谱工作站 (中国科学院研究生院应用化学研究所 ) ,石英毛细管 5 0 μｍ(ｉｄ)× 6 0ｃｍ ,有效长度约 4 4 5ｃｍ(河北永年光导纤维厂 ) ,ｐＨ ＨＪ90Ｂ型酸度计 (上海雷磁仪器厂 )。尼古丁 (ｎｉｃｏｔｉｎｅ)标样 (…     

毛细管电泳测定γ-四氢吡咯基苯丙醇的光学纯度

1　引　　言最简单的光学纯度测定方法是旋光度测定法 ,但它的可靠性较低且无法测定没有标准品的新化合物。ＮＭＲ、ＨＰＬＣ和ＧＣ也是常用的方法。近年来 ,毛细管电泳在手性分离领域中取得了很大的成功 ,它也能用于光学纯度的测定。本文研究了用毛细管电泳法测定新合成的手性化合物γ 四氢吡咯基苯丙醇的光学纯度。2　实验部分2 1　仪器与试剂　ＳｐｅｃｔｒａＰＨＯＲＥＳＩＳ10 0 0 ＴＭ 毛细管电泳仪 (美国ＴＳＰ公司 ) ,5 0 μｍＩＤ弹性石英毛细管 (河北永年锐沣色谱器件有限公司 )。β 环糊精聚合物由北京理工大学化工与材料学院合…     

毛细管电泳法测定白头翁汤中黄连和黄柏共煎生物碱的煎出量

 建立了利用毛细管电泳简便、准确地测定白头翁汤中黄连和黄柏共煎生物碱煎出量的方法。采用自组装毛细管电泳装置,采用75μmi.d.×50cm弹性石英毛细管,以0 05mol/LNa2B4O7 CH3OH(体积比为85∶15)溶液作缓冲液,运行电压为14kV,检测波长为232nm。另外,通过实验优化了提取溶剂中乙醇的含量。实验结果表明:以小檗碱、巴马汀提取量为指标,30%(体积分数)的乙醇水溶液是提取白头翁汤中黄连和黄柏共煎生物碱的最佳溶剂。小檗碱和巴马汀的质量浓度分别在15 0mg/L～65 0mg/L、12 5mg/L～50 0mg/L时与其峰面积有良好的线性关系;小檗碱的平均回收率不低于95%。     

不同剂型药用抑肽酶纯度的胶束电动毛细管测定

 以十六烷基三甲基溴化铵 (CTAB)为阳离子表面活性剂 ,用胶束电动毛细管 (MECC)分别对抑肽酶粉针剂和抑肽酶注射液进行纯度测定。实验中选择了最佳缓冲液 (含 4mmol/LCTAB的 80mmol/LNa2 HPO4 H3 PO4,pH 7 0 0 ) ,考察了进样量与样品中高浓度盐对分离的影响。并对毛细管区带电泳、MECC和高效液相的分离效果加以比较 ,表明MECC的分离效果最佳。     

高效毛细管区带电泳法分离人血清蛋白质的研究

 研究了高效毛细管区带电泳分离人血清蛋白质的电泳行为及实验条件 ,建立了分离血清蛋白质的高效毛细管区带电泳法。血清样品经硼酸缓冲液 (5 0 mmol/L,p H8.80 )稀释后 ,以 0 .1 mol/L硼酸缓冲液 (p H9.3 5 ,含4g/L PEG80 0 0 )为电泳介质 ,在 5 0 μm i.d.× 3 7cm弹性石英毛细管柱 (有效柱长为 3 2 cm)中进行电泳分离 ,以2 0 0 nm紫外波长检测。方法简便、快速、重复性好 ,1 2 min内便可完成对血清中蛋白质的电泳分离。     

毛细管区带电泳法测定复方磷酸可待因溶液有效成份

应用毛细管电泳法测定了复方磷酸可待因溶液中磷酸可待因、盐酸麻黄碱、扑尔敏的含量。毛细管电泳的条件为 :37cm× 5 0 μm i.d(有效长度 30 cm)未涂层石英毛细管柱 ;分离电压 :1 5 k V;缓冲溶液 1 5 0 mmol/L NH4 Ac- H3PO4 ( p H2 .0 )。研究了方法的线性范围、精密度、回收率等 ,测定了三批样品。实验证明方法简便、快速、准确     

8种农药的大口径毛细管气相色谱分析

1　引　　言2 0世纪 80年代 ,毛细管气相色谱 (CGC)技术就广泛用于农药残留分析。现在毛细管气相色谱与固相萃取、固相微萃取、质谱等技术一起 ,被广泛地应用于农药的多残留分析。但作为农药原药和制剂的有效成分的常规分析 ,直至进入2 0世纪 90年代后才在农药国际标准分析方法 (CIPAC)手册中相继出现。近年来 ,随着大口径毛细管推广应用和一些重大技术的改进 ,毛细管气相色谱作为农药的常规分析方法 ,发展比较快。到目前为止 ,CIPAC已经建立了近 2 0个农药原药及其制剂的毛细管气相色谱标准分析方法。大口径毛细管气相色谱法具有分析…     

HEPT类化合物的QSAR研究

为定量结构／活性相关性研究提取了量子化学参数,拓扑指数Am,分子连接性指数^mxt及疏水性常数,同时应用正交变换和最佳变量子集算法（Leaps-and-Bonds)进行了变量压缩和选择,进而实施了多元回归分析,并由此结果进行了HEPT类化合物（1－[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives)的结构／活性关系的理论解释,进行了人工神经网络法对于该类化合物的活性预测,其结构明显好于多元回归法。     

Effect of the pH of the medium on the chemical shifts in the PMR spectra and on the distribution of the π-electron density

The dependence of the chemical shifts of the ring protons on the pH of the medium for a number of 4-hydroxyquinoline derivatives was studied by means of PMR spectroscopy. The dipolar and uncharged hydroxy forms exist in equilibrium in aqueous solutions. The effect of intramolecular hydrogen bonding on the character of the dependence of the chemical shift on the pH of the medium in the case of 3-piperidinomethyl-4-hydroxyisoquinoline was investigated. The possibility of the separate protonation of the ring nitrogen and the side-chain nitrogen in 3-piperidinomethyl-4-hydroxyisoquinoline was established. The distribution of the -electron density in 4-hydroxyisoquinoline is in good agreement with its chemical behavior.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1546–1549, November, 1971     

Effect of the pH of the medium on the chemical shifts in the PMR spectra and on the distribution of the π-electron density

The dependence of the chemical shift of the ring protons on the pH of the medium for a number of 3-hydroxyquinoline derivatives was studied by PMR spectroscopy. The regions of ionization of the molecules, which correspond to the ranges of acidic, neutral, and alkaline media, were found. In D₂O, 3-hydroxyquinoline is present only in the uncharged hydroxy form. The presence of intramolecular hydrogen bonding in 4-dimethylaminomethyl-3-hydroxyquinoline has a substantial effect on the character of the dependence of the chemical shift on the pH of the medium; the existence of separate protonation of the nitrogen atoms of the ring and the side chain of 4-dimethylaminomethyl-3-hydroxyquinoline was established. The distribution of the -electron density in the 3-hydroxyquinoline molecule is in good agreement with its chemical behavior during electrophilic substitution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1540–1545, November, 1971.     

From the Micro- to the Macro-: Managing the Conservation of the Warship,Vasa

Sweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large-scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re-treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum.     

On the theory underlying the Car-Parrinello method and the role of the fictitious mass parameter

The theory underlying the Car-Parrinello extended-Lagrangian approach to ab initio molecular dynamics (CPMD) is reviewed and reexamined using "heavy" ice as a test system. It is emphasized that the adiabatic decoupling in CPMD is not a decoupling of electronic orbitals from the ions but only a decoupling of a subset of the orbital vibrational modes from the rest of the necessarily coupled system of orbitals and ions. Recent work [J. Chem. Phys. 116, 14 (2002)] has pointed out that, due to the orbital-ion coupling that remains once adiabatic decoupling has been achieved, a large value of the fictitious mass mu can lead to systematic errors in the computed forces in CPMD. These errors are further investigated in the present work with a focus on those parts of these errors that are not corrected simply by rescaling the masses of the ions. It is suggested that any comparison of the efficiencies of Born-Oppenheimer molecular dynamics (BOMD) and CPMD should be performed at a similar level of accuracy. If accuracy is judged according to the average magnitude of the systematic errors in the computed forces, the efficiency of BOMD compares more favorably to that of CPMD than previous comparisons have suggested.