首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 812 毫秒
1.
糖类化合物的结构和组成分析对于探究糖的结构与功能的关系具有重要作用。亲水作用色谱(HILIC)对糖类等极性化合物具有良好的分离效果。该文介绍了适合糖类分析的常用HILIC柱固定相及其分离机制,论述了强洗脱溶剂比例、流动相p H值、缓冲盐浓度和色谱柱温度对HILIC分离效果的影响,并举例说明了HILIC法在单糖组成、糖胺聚糖二糖组成、寡糖聚合度、糖苷、糖脂、糖醇以及N-/O-糖链分析中的应用。  相似文献   

2.
Abstract

This paper reports a method for the separation and measurement of methylated purines of interest to carcinogenesis studies by high-pressure liquid chromatography (HPLC) following their column chromatographic isolation from collected urine samples. HPLC was evaluated on three different cation-exchange columns, with optimum conditions obtained on a Partisil 10-SCX column employing isocratic elution with 0.25M (NH4)H2PO4 at pH 4.0. This column was also found to be useful for the separation of mono-methylguanine isomers. Application is shown to the analysis of rat urine following animal treatment with methyl methanesulfonate.  相似文献   

3.
As a biological affinity chromatographic method, cell membrane chromatography (CMC) using a silica stationary phase covered with specific cell membrane has been used in screening active components. The innovation of this work is that the bioactive cell membrane and the chromatographic packing are mixed and absorbed for the first time to form the pre-column. The pre-column was placed in front of a C18 column to create dynamic CMC online high-performance liquid chromatography (HPLC) system. The retention behavior and dynamic changes of pharmaceuticals were studied for this system. The results indicate that the retention time of the drug was increased and the symmetry factor reached the analytical level after the addition of the dynamic cell membrane pre-column. Therefore, the dynamic CMC coupled with HPLC system may be a potentially rapid and efficient drug analysis approach for the interaction of drug molecule and receptor on red blood cell membranes.  相似文献   

4.
Abstract

A rapid and effective method has been developed for the purification of hundred-milligram quantities of water-soluble synthetic carbohydrates. The method utilizes a 30 cm x 7.8 mm i.d. column packed with Waters Associates carbohydrate analysis packing in conjunction with isocratic water-acetonitrile elution and refractive index detection. The generality of this method is illustrated by its application to 13 sucrose derivatives and one derivative each of D-fructose and α,α-trehalose.  相似文献   

5.
Activated charcoal column chromatography was successfully applied for preparative extraction of artemisinin with high-purity from Artemisia annua L. in one single run for the first time in this study. The adsorption kinetics study showed that powdery activated charcoal had high adsorption speed for artemisinin. The experimental adsorption data fitted well using the Langmuir adsorption model. The optimal parameters for the extraction of artemisinin were obtained using a column packed with activated charcoal: the loading amount, 1 g extract/5 g activated charcoal; the elution mode, CH2Cl2?CMeOH (2:5, v/v) for 5 BV (bed volume) after the removal of some impurities with CH2Cl2?CMeOH (1:10, v/v). With this optimized condition, artemisinin was finally obtained with purity at 95.2% and the recovery at 72.3%. The developed technique would provide a feasible large-scale method for the extraction of artemisinin in pharmaceutical industry.  相似文献   

6.
基于微机电系统(Micro-electro-mechanical systems,MEMS)技术,制作了微型气相色谱柱,并对其性能进行了研究。与传统色谱柱相比,此微型色谱柱具有体积小,分析速度快等特点,适用于在线检测分析与监测。本研究利用深刻蚀技术与动态涂覆固定相的方法,设计制作了0.5,1.0及3.0 m色谱柱,实现了对苯,甲苯和邻二甲苯的分离。其中,3.0 m色谱柱对甲苯和邻二甲苯的分离度达14.3,理论板塔数达6160,分离时间少于200 s。考察了柱长对色谱柱分离性能的影响。此微型色谱柱可广泛应用于家居安全,瓦斯监测以及环境检测等领域。  相似文献   

7.
Summary A capillary restrictor for supercritical fluid chromatography (SFC) with CO2 was made by using a micro torch and fine emery cloths or grinding blocks. This restrictor could be drawn out either directly from the end of the analytical capillary column, or from a short piece of any capillary, which was then connected to the analytical column by standard techniques. It was found that the base current of a flame ionisation detector (FID) depends strongly on the position of the capillary end with respect to the FID flame tip and on the CO2 grade, of course. Best results have been achieved at around 5 to 7 mm distance between the restrictor and the flame tip ends, and using SFC grade CO2.  相似文献   

8.
Abstract

High pressure liquid chromatography (HPLC) methods were developed for separation and plasma analysis of ten xanthine derivates. Separation was evaluated on silica column and on three different reverse phase columns, with optimum conditions obtained on C6 spherisorb column using isocratic elution with phosphate buffer 10?2 M, pH 2.7 - acetonitrile mixture (80/20 V/V). Determination of these xanthine derivates in plasma for therapeutic control was studied.  相似文献   

9.
丛景香  林炳昌 《化学进展》2007,19(11):1813-1819
多维液相柱色谱分离分析复杂样品越来越受到重视。本文介绍了国内外多维液相柱色谱的近期发展,详细讨论了二维液相色谱的实现,其中包括固定相、流动相的选择、温度变量的作用以及两维间切换的实现,并对多维液相柱色谱的应用现状进行了总结。  相似文献   

10.
王荔  葛良法 《化学研究》2009,20(4):80-82
海藻糖的积累对水稻对干旱、高盐和低温胁迫的耐受性有一定的影响,准确测定其含量对研究相关的功能有重要的意义.本文建立了转基因水稻样品中海藻糖的高效阴离子色谱测定方法,采用美国Dionex公司DX-500型离子色谱仪,Pac PA1离子色谱分离柱,以0.125 moL.L-1NaOH溶液作为流动相,利用Au工作电极、pH参比电极的脉冲安培检测器测定了水稻提取液中的海藻糖.方法的线性范围为0.02~10.0 mg.L-1,检出限为0.012 mg.L-1,标准品和样品测定的相对标准偏差分别为0.83%和1.52%.用该法测定了抗逆转基因水稻中的海藻糖,取得了较为满意的结果,加标回收率为95.3%~106.0%.所建立的方法具有高的灵敏度和精密度,适合于水稻样品中海藻糖的分析.  相似文献   

11.
In this work a fast gas chromatography set‐up with on‐column injection was optimized and evaluated with a model mixture of C8–C28 n‐alkanes. Usual injection volumes when using narrow‐bore (e. g., 0.1 mm i.d.) analytical columns are ca. 0.1 μL. The presented configuration allows introduction of 10–30‐fold larger sample volumes without any distortion of peak shapes. In the set‐up a normal‐bore retention gap (1 m×0.32 mm i. d.) was coupled to a narrow‐bore (4.8 m×0.1 mm i. d.×0.4 μm film thickness) analytical column using a low dead volume column connector. The effects of the experimental conditions such as inlet pressure, sample volume, initial injection temperature, and oven temperature on a peak focusing are discussed. H‐u curves for helium and hydrogen are used to compare their suitability for high speed gas chromatography and to show the dependence of separation efficiency on the carrier gas velocity at high inlet pressures. In the fast gas chromatography system a baseline separation of C10–C28 n‐alkanes was achieved in less than 3 minutes.  相似文献   

12.
A purely chromatographie and sufficiently general method is described for the analysis of molecular fluorine in permanent inert gases or in other corrosive fluorine compounds (UF6, HF). The method is also applied to the analysis of permanent inert gases (even in trace quantities) in the same fluorine compounds. In this method, one or several chemical “precolumns” are placed in series with a gas-liquid chromatography column. The “precolumn” system retains or destroys the corrosive compounds (UF6, HF, F2) and the chromatography column separates the components formed.  相似文献   

13.
《Analytical letters》2012,45(13):1129-1136
Abstract

A highly sensitive and selective derivatization of ketosteroids for use in high-performance liquid chromatography with electrochemical detection (HPLC/EC) is described. When the detector response for three phenylhydrazone derivatives was compared with one another using dehydroepiandrosterone, the p-nitrophenylhydrazone showed the highest sensitivity with a detection limit of 200 pg. Dehydroepiandrosterone and other principal 17-ketosteroids in human blood were quantitatively derivatized into p-nitrophenylhydrazones and efficiently separated by HPLC/EC on a μBondapak C1 8 column using 0.5%. NH4H2PO4/methanol (2:7, v/v).  相似文献   

14.
In this work, a chromatography column comparison and rapid pretreatment development were carried out. A multi‐class method was built based on the quick, easy, cheap, effective, rugged, and safe pretreatment method with hydrophilic interaction ultra high performance liquid chromatography and tandem mass spectrometry for the high‐throughput analysis of five antivirals in chicken muscle. The HSS T3 column, BEH HILIC column and BEH Amide column were studied, and their chemical functionalities and chromatographic separation effectiveness were compared. The BEH Amide column was selected to perform the mass spectrometry analysis under the hydrophilic interaction chromatography mode. First, a different strategy without adding MgSO4 and NaCl into the muscle samples was considered. Then, different concentrations of formic acid, acetic acid, and ammonia in acetonitrile were compared for better extraction efficiency. Nine sorbents (C18, PSA, NH2, Florisil, Alumina‐B, Alumina‐N, PestiCarb, NANO, and NANO‐NH2) were studied. The optimized procedure consisted of the use of 10% acetic acid in acetonitrile for the extraction solvent and NANO‐NH2 for clean‐up. NANO‐NH2 had not been applied in other matrix and pollutants so far. The developed method provided favorable trueness, precision, and acceptable matrix effect. Meanwhile, the method was sensitive, the limits of detection of amantadine, rimantadine, acyclovir, ribavirin, and moroxydine achieved were 0.56, 0.50, 0.30, 2.22, and 0.51 μg/kg, respectively, and were successfully applied for the routine detection of antivirals in the chicken samples.  相似文献   

15.
多维高效液相色谱分离模式组合   总被引:5,自引:0,他引:5  
刘照胜  李永民  蒋生祥  陈立仁 《色谱》1997,15(6):490-493
简述了多维高效液相色谱法的特点及发展简况,重点对分子排阻色谱/反相色谱、离子交换色谱/反相色谱、正相色谱/反相色谱、分子排阻色谱/离子交换色谱、液固色谱/反相色谱、亲合色谱/反相色谱、非手性柱/手性柱等的联用模式及实际应用进行了概括和总结。  相似文献   

16.
An ion-exclusion chromatography (IELC) comparison between a conventional ion-exchange column and an ultra high-performance liquid chromatography (UHPLC) dynamically surfactant modified C18 column for the separation of an aliphatic carboxylic acid and two aromatic carboxylic acids is presented. Professional software is used to optimize the conventional IELC separation conditions for acetylsalicylic acid and the hydrolysis products: salicylic acid and acetic acid. Four different variables are simultaneously optimized including H2SO4 concentration, pH, flow rate, and sample injection volume. Thirty different runs are suggested by the software. The resolutions and the time of each run are calculated and feed back to the software to predict the optimum conditions. Derringer’s desirability functions are used to evaluate the test conditions and those with the highest desirability value are utilized to separate acetylsalicylic acid, salicylic acid, and acetic acid. These conditions include using a 0.35 mM H2SO4 (pH 3.93) eluent at a flow rate of 1 mL min?1 and an injection volume of 72 μL. To decrease the run time and improve the performance, a UHPLC C18 column is used after dynamic modification with sodium dodecyl sulfate. Using pure water as a mobile phase, a shorter analysis time and better resolution are achieved. In addition, the elution order is different from the IELC method which indicates the contribution of the reversed-phase mode to the separation mechanism.  相似文献   

17.
高效液相色谱法测定氨基酸的研究进展   总被引:1,自引:0,他引:1  
氨基酸是构成生物体的基础物质,氨基酸分析是生命科学研究中最重要的领域之一。高效液相色谱法因分析速度快、操作简便、检测灵敏、适用范围广等优点而广泛应用于食品工业、制药工业、生命科学研究等领域。该文综述了高效液相色谱分析氨基酸的方法,包括柱后衍生法、柱前衍生法、高效阴离子交换色谱-积分脉冲安培检测法和高效液相色谱-蒸发光散射检测法。并对上述方法进行了比较,为日常的氨基酸分析提供了参考。  相似文献   

18.

An ion-exclusion chromatography (IELC) comparison between a conventional ion-exchange column and an ultra high-performance liquid chromatography (UHPLC) dynamically surfactant modified C18 column for the separation of an aliphatic carboxylic acid and two aromatic carboxylic acids is presented. Professional software is used to optimize the conventional IELC separation conditions for acetylsalicylic acid and the hydrolysis products: salicylic acid and acetic acid. Four different variables are simultaneously optimized including H2SO4 concentration, pH, flow rate, and sample injection volume. Thirty different runs are suggested by the software. The resolutions and the time of each run are calculated and feed back to the software to predict the optimum conditions. Derringer’s desirability functions are used to evaluate the test conditions and those with the highest desirability value are utilized to separate acetylsalicylic acid, salicylic acid, and acetic acid. These conditions include using a 0.35 mM H2SO4 (pH 3.93) eluent at a flow rate of 1 mL min−1 and an injection volume of 72 μL. To decrease the run time and improve the performance, a UHPLC C18 column is used after dynamic modification with sodium dodecyl sulfate. Using pure water as a mobile phase, a shorter analysis time and better resolution are achieved. In addition, the elution order is different from the IELC method which indicates the contribution of the reversed-phase mode to the separation mechanism.

  相似文献   

19.
20.
Abstract

An isocratic high-performance liquid chromatography method is described for the determination of Neopterine eliminated in human urine, using a μ-Bondapak C18 column (300 × 3.9 mm I.D.) and a strongly polar phosphate buffer (pH 6.2) for elution. This analysis requires only 15 minutes and allows very good reproduc-tibility of retention times. This method is well-suited for automation and routine clinical laboratory in order to quantify human urinary Neopterine in healthy subjects and in subjects with malignant disorders.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号