高效液相色谱-核磁共振仪联用技术在耐哌地尔杂质检测中的应用

用高效液相色谱-核磁共振（HPLC-CNM）联用技术中的连续流动和停止流动两种模式对萘哌地尔中杂质进行检测,根据^1HNMR,^1H-^1HCOSY谱完成了主要杂质1-萘环-丙三醇结构鉴定。HPLC-NMR是解决合成药物中杂质结构确证的简便、快速方法。     

Comparison of High Performance Liquid Chromatography with 1H Nuclear Magnetic Resonance Spectrometry for the Quantitative Analysis of Pyrrolizidine Alkaloids from Senecio Vulgaris

Abstract

A high-performance liquid chromatographic method for the analysis of pyrrolizidine alkaloids from Senecio vulgaris has been developed using narceine-HCl as an internal standard. A reversed phase procedure with a methanol/.01 M KH₂PO₄30/70 solvent system is described, and compared with a quantitative¹H Nuclear Magnetic Resonance spectrometric method. Some advantages and limitations are discussed.     

基于核磁和质谱分析技术的代谢组学在癌症诊断中的应用

本文对近年来用于癌症诊断的新方法——代谢组学及其在该领域内的应用进行了简要介绍.代谢组学通过定性与定量测量生物样本(血液、尿液、组织等)中数以千计的小分子代谢物,可灵敏地反映代谢组中与病理状态有关的细微变化,从而可为癌症的早期诊断及更好地理解癌变过程提供一种新颖的思路.本文还讨论了代谢组学与系统生物学中其它一些组学在癌症检测上的关联,介绍了一些用代谢组学进行不同癌症的诊断、治疗监测以及药物开发的前期研究工作,并探讨了用于临床癌症诊断的代谢组学方法所面临的机遇、挑战与未来发展方向.     

Analysis of Cyclocitral Mixtures by Nuclear Magnetic Resonance Spectroscopy

Abstract

Adequately separated signals in the nuclear megnetic resonance spectra of mixtures of cyclocitrals were assigned to the individual components. This assignment allowed direct integration of the signals of interst and calculation of the percentages of α-cyclocitral, β-cyclocitral, para-cymene, and 1-acetyl-4, 4-dimethyl-1-cyclohexene. The rapidity and nondestructive nature of the nuclear magnetic resonance analysis are superior to the fractional crystallization of the semi-carbazones and gas chromatography techniques previously utilized.     

扩散加权的核磁共振方法在高血脂症血清快速识别中的应用

研究了扩散加权的NMR在区分冠心病患者和正常人的血清中的可能应用,证明了扩散加权的NMR与主成分分析(PCA)相结合是将冠心病血清从正常血清中识别出来的有效方法。分子自扩散运动加权的NMR能够有效抑制小分子代谢物的共振信号强度,从而使血脂和血蛋白的NMR特征更为明显。最佳的扩散权重因子(b)约为0.85×107s/cm2,增加或降低扩散权重因子都会影响识别效率。研究结果表明,分子量极小的代谢物(乳酸等)及相对较大的脂蛋白(VLDL)对区分两类血清的贡献较小。在最佳的b值条件下,高密度脂蛋白(HDL)和低密度脂蛋白(LDL)对区分两类血清的贡献得以提高,从而获得更好的区分效果。     

Polyvinylacetate Gel Permeation Chromatography of H-Coal Liquids and Model Compounds. Comparison with Rigid Gel,Reversed Phase and Normal Phase Chromatography

Abstract

This paper reports the application of polyvinylacetate gel (Fractogel) for size fractionation of the H-Coal liquids and model aromatic hydrocarbons. The four H-Coal liquids were each divided into three classes according to solubility in hexane, benzene, and pyridine. A model mixture of eight compounds when applied to the Fractogel column yielded four fractions; a similar performance was given by a prepacked, Toyo Soda microparticulate column containing styrene-divinylbenzene copolymer. Regarding the twelve H-Coal solvent fractions, the chromatograms obtained from the Fractogel column were analogous to those from the Toyo Soda column. By making further use of model compounds, the Fractogel results are compared with those obtained from reversed phase chromatography on a Partisil ODS column and those from normal phase chromatography on a LiChrosorb silica column. These comparisons reveal the usefulness in separating certain aromatic hydrocarbons by the Fractogel column. Furthermore, judging from the chromatograms of a hexane-soluble H-Coal fraction obtained by the reversed phase and normal phase methods, the ODS column will complement the Fractogel column in fractionating the H-Coal liquids.     

Calibration in High Temperature Gel Permeation Chromatography of Linear Polyethylenes

Abstract

The mathematical relationship between the gel permeation chromatography calibration curves of polystyrene and linear polyethylene has been determined in 1,2,4-trichlorobenzene at 130, 135 and 140°C. The experimentally determined relationship is in good agreement with that predicted from application of the principles of the universal calibration technique and published Mark-Houwink coefficients. Definition of this relationship enables the use of polystyrene as a secondary standard for gel permeation chromatographic determination of linear polyethylene molecular weight determinations.     

高效凝胶渗透色谱法在若干重质化工产物分析中的应用

为配合酚醛树酯、十八烷基苯乙烯基醚聚合物新材料的生产、催化条件下煤直接液化的研究,建立了各试样分子量表征的高效凝胶渗透色谱法（ＨＰＧＰＣ）,高分辨地测定了分子量分布、重均分子量Ｍｗ、数均分子量Ｍｎ。表征了不同产品的组成特性,有效地指导了工艺生产和基础研究。     

Determination and Characterization of Photocatalytic Products of Linear Alkyl Sulphonate by High Performance Liquid Chromatography and Nuclear Magnetic Resonance

In this study, Linear Alkyl Sulfonate (LAS) as anionic detergent active compounds was treated with photocatalytic method. The method degrades LAS to form CO₂ and H₂O. Time variations performed to the photocatalysis was conducted hour to hour, from 1 to 5 hours. Determination of LAS concentration was carried out using methylene blue active substances (MBAs), whereas characterization of LAS structure was observed using high performance liquid chromatography (HPLC) and nuclear magnetic resonance spectrometry (NMR). The results showed that 69.9% of LAS decomposes 65.1% of CO₂ are formed.     

大鼠血液中溴莫普林的代谢产物核磁共振氢谱和质谱研究

用核磁共振氢谱和质谱法研究大鼠血浆中溴莫普林（BDP)及其代谢物。首先用固相萃取法将血液中内源性物质除去,然后经核磁共振氢谱和质谱检测大鼠血液中BDP及其代谢物。大鼠服用溴莫普林后20h时血浆中检测到两个代谢产物：脱甲基－溴莫普林葡萄糖醛酸和溴莫普林硫酸。结果证明核磁共振氢谱和质谱法可以快速、方便地用于血液中药及其代谢产物的含量与结构检测的研究。     

Liquid Chromatography Tandem Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy of Magnesium (II) Gluconate Solution

Magnesium gluconate is a classical pharmaceutical compound used as a source of magnesium for the prevention and treatment of hypomagnesemia. To the best of our knowledge, a robust and reliable liquid chromatography tandem mass spectrometry technique has not yet been reported for the qualitative and quantitative analysis of magnesium gluconate. This study describes the method development for the LC–ESI–MS/MS analysis of magnesium gluconate using three different reversed-phase HPLC conditions (Method I–III) with comprehensive fragmentation pattern and the structural characterization by NMR spectroscopy. The LC–MS and NMR data were found in accordance with the structure of magnesium gluconate. When magnesium gluconate was dissolved in the acetonitrile and water–methanol solutions, it exists in situ in three different forms: magnesium gluconate itself, gluconic acid, and magnesium gluconate chelate with gluconic acid by a coordinate covalent bond. Method I exhibited pseudo-molecular ion peaks with more magnesium gluconate chelates with gluconic acid, while method II showed an adduct of magnesium gluconate with the solvent along with the molecular ion peak. There was no pseudo-molecular ion peaks found in method III. Thus, method III was found to be the more accurate, robust and reliable LC–MS method for the qualitative and quantitative analysis, structural characterization, and could also be suitable for the pharmacokinetic study of magnesium gluconate. The detailed fragmentation analysis might be useful for the structural characterization of unknown divalent organometallics.     

Determination of Pentacyclic Triterpenes from Betula utilis by High-Performance Liquid Chromatography and High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy

A rapid and reliable method was developed and validated for determining betulin and betulinic acid in bark in Betula utilis by high-resolution magic angle spinning ¹H nuclear magnetic resonance (HR-MAS NMR) spectroscopy. HR-MAS NMR spectroscopy clearly distinguished the resonances of betulin and betulinic acid in the bark of all accessions of B. utilis. The concentrations of betulin and betulinic acid were calculated and added to the spectra. The determination of the targeted metabolites in chloroform extract of bark of each accession of B. utilis was performed by high-performance liquid chromatography (HPLC). Quantitatively, betulin was present at higher concentrations than betulinic acid in all accessions. The HR-MAS NMR and HPLC results showed that betulin and betulinic acid varied significantly among accessions of B. utilis. Principal component analysis of the NMR and HPLC results provided classification into three metabolic groups in which the betulin concentration was high, moderate, or low. The results show that HR-MAS NMR is rapid for fingerprinting of betulin and betulinic acid in the bark of B. utilis, while minimizing the drawbacks associated with solvent extraction.     

高场核磁共振波谱在多糖结构研究中的应用

随着高场核磁共振波谱（ＮＭＲ）技术飞速发展,它在多糖的结构研究中发挥着日益重要的作用,不仅对共 结构,而且对于多糖在溶液中或固体状态下的构象以及动力学特性,ＮＭＲ分析也是最有力的工具。本文综述了高场ＮＭＲ技术在分析多糖结构方面的应用。     

Use of Gel Permeation Chromatography in the Crime Laboratory

Abstract

In this study, the ways in which GPC can be integrated into the crime laboratory's present analytical scheme for polymer products will be examined. Fingerprint chromatograms and chromatograms illustrating molecular weight determination of two types of commonly encountered physical evidence (fibers and tail light lense fragments) will be compared and discussed. The techniques involved in sample preparation and data interpretation will be given. Finally the potential advantages of GPC for use in the crime laboratory will be presented.     

3种聚酰亚胺分子的核磁共振碳谱及氢谱的分析

本文报道了３种高性能聚酰亚胺的核磁共振定量碳谱及氢谱。利用这３种样品化学结构的相似性，根据ＰＥＩ和ＤＥＰＴ谱，ＰＥＩ和ＰＯＩ的二维同核化学位移相关谱，碳氢自旋晶格驰豫时间以及化学位移的理论计算，详细分析并归属了３种聚酰亚胺的碳谱峰和氢谱峰，同时验证了其重复单元结构的正确性。     

稀土对大鼠代谢产物影响的核磁共振研究

以高场核磁共振技术为研究手段,通过分析腹腔注射０．２、２、１０、２０ｍｇ／ｋｇ体重剂量的Ｌａ（ＮＯ３）３后大鼠尿液中代谢物浓度、物种的变化,研究了稀土化合物在动物体内的作用情况,结果表明,稀土的引入使动物肾脏和肝脏都受到一定程度的损伤,并在代谢物中挑选出了合适的ＮＭＲ ｍａｒｋｅｒｓ,其变化可以反映稀土离子作用后大鼠的异常代谢。     

红外光谱与核磁共振波谱在甲壳素结构研究中的应用

本文综述了红外光谱和核磁共振波谱在甲壳素和壳聚糖的乙酰度、衍生物的取代位置和取代度、晶体结构和结晶度以及构型和构象、与离子和其他分子间的相互作用等研究领域的应用状况,引用文献61篇。