四种神经肽的反相高效液相色谱法分离

以反相高效液相色谱法（ＲＰ－ＨＰＬＣ）分离甲硫脑啡肽（ＭＥＫ）、亮脑啡肽（Ｌｅｕ－ＥＮＫ）、强啡肽Ａ１－１７（ＤｙｎＡ１－１７）、胆囊收缩素（ＣＣＫ－８ｓ）。色谱柱为ＺＯＲＢＡＸＣ１８（２．１ｍｍＩＤ×１５０ｍｍ）；流动相：乙腈／水／三氟乙酸（ＴＦＡ），梯度洗脱，紫外检测器检测：ＵＶ２１５ｎｍ。上述条件下，四种神经肽在微克水平得到较好分离。     

高效液相色谱法测定箭叶淫羊藿中淫羊藿苷的含量

箭叶淫羊藿用70%乙醇回流提取,取部分提取液直接干燥得淫羊藿提取物,以高效液相色谱法测定箭叶淫羊藿中淫羊藿苷的含量,色谱柱为InertsilODS-3柱,流动相为乙腈-水(27∶73),检测波长为270nm。在此条件下,淫羊藿苷与其它黄酮醇苷的色谱峰分离完全,平均回收率为99.46%。该法可用于淫羊藿药材的质量控制。     

氢化物发生—冷阱捕获—色谱分离—原子吸收法测定天然水中坤的形态

研究建立了氢化物发生－冷阱捕获－色谱分离－原子吸收方法测定天然水中四种主要砷形态，测试系统自行组装，色谱柱填料采用ＣｈｒｏｍｏｓｏｒｂＧＡＷ－ＤＭＣＳ（粒径０．３～０．４５ｍｍ），其上涂布３％ＯＶ－１０１。方法的检出限以砷计分别为：Ａｓ（Ｖ）０．５１ｎｇ，Ａｓ（Ⅲ）０．４３ｎｇ，ＭＭＡ０．３８ｎｇ，ＤＭＡ０．６７ｎｇ；１２ｎｇ砷标准偏差为Ａｓ（Ⅴ）４．２１％，Ａｓ（Ⅱ）３．５６％，ＭＭＡ３．２３％     

β－甲基地高辛药物中有关物质的检测

报道了用高效液相色谱法检测β－甲基地高辛中的有关物质。色谱条件：色谱柱用ＳｐｈｅｒｉｓｏｒｂＣ_（１８），１０μｍ，４．６ｍｍ×１５０ｍｍ，检测波长２１８ｎｍ，流动相：乙腈－水（３４：６６）。检测结果提示，目前的精制工艺需进一步改进。     

β－甲基地高辛药物中有关物质的检测

 报道了用高效液相色谱法检测β－甲基地高辛中的有关物质。色谱条件：色谱柱用ＳｐｈｅｒｉｓｏｒｂＣ_（１８），１０μｍ，４．６ｍｍ×１５０ｍｍ，检测波长２１８ｎｍ，流动相：乙腈－水（３４：６６）。检测结果提示，目前的精制工艺需进一步改进。     

高效液相色谱法测定朝鲜淫羊藿中淫羊藿甙的含量

采用高效液相色谱法测定朝鲜建羊藿中淫羊藿成的含量,色谱柱为Shim-PackCLC-ODS柱,流动相为乙睛-水（30:70）,检测波长270um。在此条件下,淫羊藿式与其它黄酮醇咸的色谱峰分离完全。方法回收率为976％,RSD为1.2％,操作简便,结果可靠,为淫羊藿药材的质量控制提供了新的方法。     

高效液相色谱法鉴别不同的分散染料

用高效液相色谱法测定了１００余种不同来源的分散染料。色谱柱为ＮｏｖａｐａｋＣ_（１８）柱（１５０ｍｍ×３．９ｍｍｉ．ｄ．）,流动相为甲醇－水（８５：１５,Ｖ／Ｖ）,检测波长为４３６ｎｍ和５４６ｎｍ。     

肿瘤细胞中长春新碱的高效液相色谱法测定

长春新碱（ＶＣＲ）为重要和常用抗肿瘤药物之一。肿瘤细胞耐药性是导致化疗失败的主要原因。为了筛选耐药细胞的逆转剂,建立了测定肿瘤细胞内ＶＣＲ浓度的高效液相色谱法,色谱条件为：Ｚｏｒｂａｘ－ＯＤＳ反相柱２５ｃｍ×４．６ｍｍｉ．ｄ．,流动相：０．０２ｍｏｌ／ＬＫ２ＨＰＯ４（ｐＨ６．６）∶ＣＨ３ＯＨ（２０∶８０,Ｖ／Ｖ）,流速：１．０ｍＬ／ｍｉｎ,检测波长：２６７ｎｍ。方法简单、快速、选择性好,在１０～２００ｍｇ／Ｌ范围内ＶＣＲ浓度－峰高呈良好的线性关系（ｒ＝０．９９９８）,仪器灵敏度为４ｎｇ。     

测定大豆和葛根中异黄酮的高效液相色谱法

建立了测定大豆和葛根７种异黄酮成分的高效液相色谱法,采用日本岛ｈｉｍ－ＰａｃｋＣＬＣＯＤＳ柱「１５０ｍｍ＊６．０ｍｍＩＤ;５μｍ）,Ｖ甲醇：Ｖ醋酸：Ｖ水＝３０：３．５：６６．５体系为流动相,０－８．５ｍｉｎ时流动相流速为１．０ｍＬ／ｍｉｎ,８．５－４７ｍｉｎ时流速为１．５ｍＬ／ｍｉｎ,柱温５０℃,检测波长２５４ｎｍ,外标法定量。     

反相高效液相色谱法测定光诱导反应产物N-(α-萘基)咔唑和N-(β-萘基)咔唑含量

报道了以Ｗａｔｅｒｓ ＢｏｎｄａｐａｋＴＭ，ＯＤＳ—Ｃ１８为色谱柱，甲醇：四氢呋喃：水（７２：６：２２，Ｖ／Ｖ为 流动相，在ＵＶ２５４ｎｍ为测定波长的条件下，利用外标法定量，建立了反相高效液相色谱法测 定光诱导反应粗产物中Ｎ－（α－萘基）咔唑和Ｎ－（β－萘基）咔唑的方法。为光诱导自由基链式亲 核取代反应（ＳＲＮ１）反应机理的探讨提供了可靠的理论依据。     

多巴胺在聚2,4,6-三甲基吡啶修饰电极上的电化学行为

用循环伏安法制备了聚 2 ,4 ,6 三甲基吡啶修饰玻碳电极 ,研究了神经递质多巴胺在该聚合物薄膜修饰电极上的电化学行为。实验结果表明 :在pH 7.4磷酸盐缓冲溶液中 ,多巴胺在该修饰电极上的线性范围为4 .0× 10 -6～ 1.0× 10 -5mol/L。该修饰电极对抗坏血酸无响应 ,从而可有效消除其对多巴胺测定的干扰     

Analysis and assessment of the occurrence, the fate and the behavior of nanomaterials in the environment

Nanomaterials have one dimension <100 nm and possess physico-chemical properties dictated by their unusually small size, large surface area, shape and chemical composition. New properties of nanomaterials have boosted their production and industrial applications in many fields (e.g., microelectronics, catalysis, fuel cells, materials science, textiles, biotechnology and medicine). In biomedical fields, nanomaterials are of the appropriate dimensions to interact with biological matter. However, they may also have negative effects on biological systems. Nanotechnology is a major, innovative, scientific and economic growth area, but the increasing production and use of nanomaterials have led to calls for more information regarding the potential impacts that their release may have on human health and the environment.This review addresses analytical approaches for characterization and quantification of nanomaterials in the environment and recent studies on their occurrence, fate and behavior.     

New study of the stability and of the spectroscopy of the molecular anions NCO- and CNO-

Using highly correlated wave functions, the ground and the low lying excited states of the molecular NCO(-) and CNO(-) anions have been reinvestigated. The stability of the electronic ground state of the two isomers with respect to dissociation and to electron detachment has been checked along the isomerization pathway. The regions of stability of the excited electronic states have been analyzed and identified and it is shown that only the ground state is stable and the corresponding potential energy surface presents three equilibrium positions. The rovibronic spectroscopy of the X (1)Σ(+) state of both NCO(-) and CNO(-) isomers has been determined by a variational approach leading to remarkable agreement with experimental data.     

McBain and the centenary of the micelle

In 1913, J.W. McBain introduced the word “micelle” into surface and colloid chemistry in the context of the association of surfactant molecules in aqueous solution. This article gives a biographic account of McBain, and reviews the early work on micellar aggregation, leading up to the pioneering ideas of G.S. Hartley who introduced the first model of the spherical micelle that we would recognise today.     

The energy pump and the origin of the non-equilibrium flux of the dynamical systems and the networks

The global stability of dynamical systems and networks is still challenging to study. We developed a landscape and flux framework to explore the global stability. The potential landscape is directly linked to the steady state probability distribution of the non-equilibrium dynamical systems which can be used to study the global stability. The steady state probability flux together with the landscape gradient determines the dynamics of the system. The non-zero probability flux implies the breaking down of the detailed balance which is a quantitative signature of the systems being in non-equilibrium states. We investigated the dynamics of several systems from monostability to limit cycle and explored the microscopic origin of the probability flux. We discovered that the origin of the probability flux is due to the non-equilibrium conditions on the concentrations resulting energy input acting like non-equilibrium pump or battery to the system. Another interesting behavior we uncovered is that the probabilistic flux is closely related to the steady state deterministic chemical flux. For the monostable model of the kinetic cycle, the analytical expression of the probabilistic flux is directly related to the deterministic flux, and the later is directly generated by the chemical potential difference from the adenosine triphosphate (ATP) hydrolysis. For the limit cycle of the reversible Schnakenberg model, we also show that the probabilistic flux is correlated to the chemical driving force, as well as the deterministic effective flux. Furthermore, we study the phase coherence of the stochastic oscillation against the energy pump, and argue that larger non-equilibrium pump results faster flux and higher coherence. This leads to higher robustness of the biological oscillations. We also uncovered how fluctuations influence the coherence of the oscillations in two steps: (1) The mild fluctuations influence the coherence of the system mainly through the probability flux while maintaining the regular landscape topography. (2) The larger fluctuations lead to flat landscape and the complete loss of the stability of the whole system.     

Use of Isotope Effects To Understand the Present and Past of the Atmosphere and Climate and Track the Origin of Life

Stable isotope ratio measurements have been used as a measure of a wide variety of processes, including solar system evolution, geological formational temperatures, tracking of atmospheric gas and aerosol chemical transformation, and is the only means by which past global temperatures may be determined over long time scales. Conventionally, isotope effects derive from differences of isotopically substituted molecules in isotope vibrational energy, bond strength, velocity, gravity, and evaporation/condensation. The variations in isotope ratio, such as ¹⁸O/¹⁶O (δ¹⁸O) and ¹⁷O/¹⁶O (δ¹⁷O) are dependent upon mass differences with δ¹⁷O/δ¹⁸O=0.5, due to the relative mass differences (1 amu vs. 2 amu). Relations that do not follow this are termed mass independent and are the focus of this Minireview. In chemical reactions such as ozone formation, a δ¹⁷O/δ¹⁸O=1 is observed. Physical chemical models capture most parameters but differ in basic approach and are reviewed. The mass independent effect is observed in atmospheric species and used to track their chemistry at the modern and ancient Earth, Mars, and the early solar system (meteorites).     

Isolation and identification of the anti-isohumulones and the anti-acetylhumulinic acids

The anti-isohumulones [5-(3-methylbutanoyl)-2-(3-methylbut-2-enyl)-4-hydroxy-4-(4-methylpent-3-enoyl)-cyclopentane-1,3-diones] and the anti-acetylhumulinic acids [5-(3-methylbutanoyl)-2-(3-methylbut-2-enyl)-4-ethanoyl-4-hydroxy-cyclopentane 1,3-diones] have been isolated from an isomerisation reaction mixture of humulone [2-(3-methylbutanoyl)-4,6-di(3-methylbut-2-enyl)-6-hydroxy-cyclohexane-l,3,5-trione] by counter-current distribution and identified by spectroscopic techniques. The formation mechanism is presented and the stereochemical consequences are discussed. The anti-isohumulones are the most bitter hop compounds presently known.     

Decorating step-by-step and independently the surface and the core of dendrons

Dendrons possessing one activated vinyl group at the core and several chlorine atoms at the end of the branches are used as starting materials to study the possibility to react independently the surface functions and the core function. In particular, the most powerful sequence of reactions for decorating them by organometallic complexes as end groups and amine or alcohol at the core has been determined. In the first step, phenol phosphines are grafted as end groups of the dendrons, and they can be used for the complexation of metals. However, these phosphines must be kept free when amines are used to react with the vinyl core in the next step. Depending on the type of phosphine end groups and on the type of function of the core (amine or alcohol), the complexation of ruthenium ([RuCl₂(p-cymene)]₂) and rhodium ([RhCl(COD)]₂) derivatives by the phosphine end groups can occur without side reaction at the core.     

Influence of the molecular structure and the nature of the solvent on the absorption and fluorescence characteristics of rhodamines

A study of the equilibrium of the molecular forms of rhodamine 19 in aqueous and ethanolic solution is carried out by determining the absorption and fluorescence characteristics of the zwitterionic and the cationic forms of the dye. The optical properties of rhodamine 19 are compared with those obtained for rhodamine 6G and also with those previously reported for rhodamine 3B and for the molecular forms of rhodamine B in water and ethanol. Different aspects of the molecular structure of the rhodamines and solvent effects are discussed, as well as their influence on the photophysical properties of the rhodamines. The aggregation of the molecular forms of rhodamine 19 is also studied in water and ethanol.