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1.
中药物质基础复杂,对其活性成分的分离一直是中药研究的难题.基于高压制备液相的多维色谱系统在高压制备液相色谱的基础上,结合了多种分离技术,极大地提高了色谱系统的分离性能和分离效率,更有利于对物质基础复杂的中药样品进行分离纯化.本文介绍了基于高压制备液相系统的多维色谱系统的基本原理、分离模式以及关键技术,并综述了其在中药分离纯化中的应用.  相似文献   

2.
采用嫁接法制备了一种新型高效液相色谱固定相.考察了固定相的液相色谱保留行为,发现该键合相具有很强的阴离子交换作用,还同时存在反相疏水作用.利用其疏水作用,可以对一些简单的有机化合物进行分离.  相似文献   

3.
合成了3,5-二硝基苯甲酰化β-环糊精键合硅胶手性固定相,并用红外光谱和X射线光电子能谱进行了表征.制备了相应的高效液相色谱柱,在高效液相色谱中,考察了该手性柱的柱效和对于一些位置异构体和对映异构体的手性分离能力.结果表明,该固定相对于一些位置异构体和对映异构体具有较好的分离能力.  相似文献   

4.
夏立钧  陶凤群  胡振元 《色谱》1988,6(2):73-76
〕本文对在线富集—高效液相色谱分析法中影响色谱分离的一些因素进行了探讨。实验表明,采用填装较小粒度富集剂的短柱及减小富集物的洗脱体积能使色谱分离获得改善。富集柱与HPLC柱间的匹配对色谱分离起着重要作用。方法适宜于分离具有较大k'值的水中痕哿坑有机物。  相似文献   

5.
逆流色谱研究进展   总被引:1,自引:0,他引:1  
逆流色谱(Counter-current chromatography,CCC)是以分析物在液-液两相溶剂中的分配差异为核心的快速分离技术.近年来,逆流色谱对复杂样品的分离,尤其是对天然产物的分离已获得广泛的关注.本文综述了近年来逆流色谱在仪器改进、溶剂体系筛选等领域的研究进展,并介绍了CCC在分离手性化合物中的应用前景.最后,对该领域未来的研究内容进行了展望.  相似文献   

6.
张养军  李翔  耿信笃 《分析化学》2002,30(5):544-547
用厚度为 1cm、而直径不同的色谱饼 (或饼形色谱柱 )对 7种蛋白质进行了色谱谱分离 ,得出了柱长与柱径比对生物大分子分离度影响不大的结论。还对柱内腔几何体积相同、而柱长 柱径比不同的色谱柱和色谱饼对分离度的影响以及它们压力降作了比较 ,结果表明色谱饼可在几乎不降低分离度的前提下显著降低色谱系统的压力。通过对 1 0× 5 0mmI.D .色谱饼体积和质量负载量以及质量回收率的测定 ,表明色谱饼对生物大分子的分离已达到制备规模。  相似文献   

7.
本文考察了氨基苯磺酸和氨基萘磺酸染料中间体在反相离子对色谱和离子色谱中的分离行为,结果表明一些异构体在反相色谱中的保留顺序与离子色谱中的顺序发生颠倒。静电作用力在离子色谱中对保留值的贡献比在反相离子对色谱中对保留值的贡献要大,而疏水作用力在反相离子对色谱中对保留值的贡献却较在离子色谱中对保留值的贡献要大。离子对色谱更有利于有机离子的分离分析。  相似文献   

8.
邹汉法  张玉奎  洪名放  卢佩章 《色谱》1994,12(4):231-233
 本文考察了氨基苯磺酸和氨基萘磺酸染料中间体在反相离子对色谱和离子色谱中的分离行为,结果表明一些异构体在反相色谱中的保留顺序与离子色谱中的顺序发生颠倒。静电作用力在离子色谱中对保留值的贡献比在反相离子对色谱中对保留值的贡献要大,而疏水作用力在反相离子对色谱中对保留值的贡献却较在离子色谱中对保留值的贡献要大。离子对色谱更有利于有机离子的分离分析。  相似文献   

9.
色谱法研究杂多酸Ⅶ: 杂多酸薄层色谱分离及测定   总被引:1,自引:0,他引:1  
本文研究了杂多酸的TBA及无机阳离子两种不同类型盐的薄层色谱特性,探讨了实验条件对两种类型杂多酸盐薄层色谱分离的影响,选择合适的条件可使杂多酸盐各组分得到分离.以薄层色谱扫描仪对分离后的样品斑点进行扫描测定,得到满意的结果.  相似文献   

10.
本文利用气相色谱—四温裂解气相色谱联用仪对一些混合物作定性分析,此方法可用来作气相色谱难分离物质的鉴定。  相似文献   

11.
合成了一种手性离子液体L-丙氨酸叔丁酯双三氟甲烷磺酰亚胺(L-AlaC4NTf2), 将其作为新型气相色谱固定相, 并与OV-1701按不同比例混合, 考察了它们的色谱性能. 研究结果表明, 该离子液体作为手性固定相的热稳定性高于175 ℃; 平均McReynolds常数为665; 在容量因子为1.02时, 理论塔板数可达每米1095块; 其对烷烃、醇类、酮类、芳香族化合物、位置异构体以及一些手性化合物具有良好的分离效果.  相似文献   

12.
Molecular organic cages as shape-persistent organic molecules with permanent and accessible cavities have attracted a lot of interest because of their importance as host-guest systems. Herein, we report a chiral porous organic cage (POC) CC9 diluted with a polysiloxane OV-1701 to fabricate a CC9-coated capillary column, which was used for the high-resolution gas chromatographic separation of organic compounds, including positional isomers and racemates. On the CC9-coated capillary column, a large number of racemic compounds such as chiral alcohols, esters, ethers and epoxides can be resolved without derivatization. By comparing the chiral recognition ability of the CC9-coated column with the commercially available β-DEX 120 column and the POC CC3-R coated column recently reported by our group, the CC9-coated column offered good resolution during the separation of some racemates, that were not separated using the β-DEX 120 column or POC CC3-R coated column. Therefore, the CC9-coated column can be complementary to the β-DEX 120 column and CC3-R coated column. The results indicated that the CC9-coated column exhibited great potential for application in the separation of positional isomers and enantiomers with great selectivity, high resolution and good reproducibility.  相似文献   

13.
制备了一种新的β-环糊精衍生物固定相2,6-二-O-戊基-3-O-[(甲基)5(烯丙基)2]-β-CD,并对其气相色谱分离性能进行研究。实验显示,该固定相具有良好的柱表面性能和较强的色谱分离能力,对一些芳香族位置异构体的分离能力优于2,6-二-O-戊基-3-O-烯丙基-β-CD衍生物,对10余种手性物质显示出较好的选择性能,且对α-位取代的丙酸酯类手性分离效果明显优于杂环类β-CD衍生物。与2,6-二-O-戊基-3-O-烯丙基-β-CD固定相的分离性能比较表明,β-CD 3位羟基部分甲基基团的引入能增强对芳香族位置异构体的选择能力,但不能明显改变烯丙基衍生物的手性分离能力。  相似文献   

14.
Ionic liquid (IL) stationary phase is especially suitable for separation of complex samples, owing to the “dual nature” of IL. In this study, a synthetic method of ionic liquid‐bonded polysiloxane (PSOIL) as stationary phase of GC was proposed. Then, the PSOIL was used to prepare an 8 m capillary column by static method. The column efficiency was measured to be about 4000 plates/m (k=3.55, naphthalene) after the column had been conditioned at 210°C. The durability of PSOIL column was better than that of the mixed stationary phase of IL and OV‐1. Moreover, the Abraham solvation parameter model was employed to characterize the PSOIL. The result revealed that the PSOIL had stronger dispersion force (l) than neat IL and stronger hydrogen bond basicity (a) than DB‐1. That meant the PSOIL might offer good selectivity for both polar and non‐polar analytes. The column exhibited unique selectivity for various organic substances, such as the homologous compounds of alkanes, esters, alcohols and aromatic compounds. It was also found that some aromatic positional isomers could be separated better on the PSOIL column than on the DB‐1 column. Furthermore, the stationary phase was suitable for separation of high‐boiling point compounds such as polycyclic aromatic hydrocarbons, phthalic esters, etc. All of these demonstrated that the PSOIL offered good selectivity and high separation efficiency for a wide range of analytes.  相似文献   

15.
Bromoacetate‐substituted [3‐(2‐O‐β‐cyclodextrin)‐2‐hydroxypropoxy]propylsilyl‐appended silica particles (BACD‐HPS), an important and useful synthetic intermediate for preparation of novel types of macrocycles‐capped β‐CD‐bonded silica particles including crown ether/cyclam/calix[4]arene‐capped β‐CD‐bonded silica particles, have been prepared and used as chiral stationary phase for HPLC. This synthetic stationary phase is characterized by means of elemental analysis. For the first time, the chromatographic behavior of BACD‐HPS was systematically evaluated with several disubstituted benzenes and some chiral drug compounds under both normal and RP conditions in HPLC. The results show that BACD‐HPS has excellent selectivity for the separation of aromatic positional isomers and chiral isomers of some drug compounds when used as stationary phase in HPLC.  相似文献   

16.
张冰雪  彭博  袁黎明 《化学通报》2021,84(3):267-272
本文使用堆砌硅珠法以硅溶胶为原料、苏氨酸(L-Thr)为手性源构造手性环境,制备具有手性分离能力的全无机介孔手性硅胶球,对其进行元素分析、红外光谱法分析、透射电镜、扫描电镜和氮气吸附等表征,采用HPLC法探究无机介孔硅胶球制备的固定相对手性异构体和苯系位置异构体的拆分性能,成功分离了9对外消旋化合物和8种苯系位置异构体...  相似文献   

17.
Metal–organic frameworks are promising porous materials. Chiral metal–organic frameworks have attracted considerable attention in controlling enantioselectivity. In this study, a homochiral metal–organic framework [Co2(D‐cam)2(TMDPy)] (D‐cam = d ‐camphorates, TMDPy = 4,4′‐trimethylenedipyridine) with a non‐interpenetrating primitive cubic net has been used as a chiral stationary phase in high‐performance liquid chromatography. It has allowed the successful separation of six positional isomers and six chiral compounds. The good selectivity and baseline separation, or at least 60% valley separation, confirmed its excellent molecular recognition characteristics. The relative standard deviations for the retention time of run‐to‐run and column‐to‐column were less than 1.8 and 3.1%, respectively. These results demonstrate that [Co2(D‐cam)2(TMDPy)] may represent a promising chiral stationary phase for use in high‐performance liquid chromatography.  相似文献   

18.
A new type of fullerene-containing polysiloxane was synthesized by reacting [60]fullerene with azidopropyl polysiloxane directly. The polysiloxanes have been used successfully as stationary phases for capillary gas chromatography. They displayed high column efficiency, wide operational temperature and high thermostability, and exhibited unique selectivity for many organic substances, such as alkanes, alcohols, ketones and aromatic compounds. The stationary phase was especially suitable for separation of high boiling-point compounds like polycyclic aromatic hydrocarbons and phthalic esters, etc. It was also found that some alcoholic or aromatic positional isomers could be well separated on the column. The influence of the fullerene content on the separation was also investigated.  相似文献   

19.
A number of chiral oxime compounds have been synthesised and their gas chromatographic analysis on both a polyethelene glycol phase column and two chiral column phases was investigated. Of particular interest to this work is the observation of dynamic interconversion behaviour, both in a single dimensional analysis, and by using comprehensive two-dimensional gas chromatography (GC × GC). A number of non-chiral compounds were studied as a means to understand the nature of the behaviour observed. As expected, the achiral compound on both the wax column and the chiral column generated two isomeric compounds—the E and Z isomers. On the wax column, a characteristic interconversion zone representing the dynamic process was observed, with extent of interconversion dependent on the conditions used. For the chiral compounds, two isomers and the interconversion zone were exhibited on the wax column, however on the chiral column 4 isomeric peaks were found—the (R) and (S) enantiomers of each of the E and Z isomers. In the case of the chiral column, the extent of interconversion was negligible, and this appears to correlate with the use of low polarity columns. In order to encourage dynamic interconversion, a polyethylene glycol column was coupled to the chiral column, by placing it either before or after the chiral column. In this case a monitor detector was employed between the two columns in order to isolate the effects of the first column from the behaviour on the second. In a further study, the most appropriate column arrangement from the earlier study was placed into a comprehensive two-dimensional gas chromatography instrument, with a wax-phase column in the second dimension. The unique location of peaks for each of the molecules in 2D space and patterns for the interconversion processes is interpreted phenomenologically.  相似文献   

20.
酰胺型杯[4]聚硅氧烷用作气相色谱固定相的研究   总被引:1,自引:0,他引:1  
叶汉英  林琳  吴采樱 《分析化学》1999,27(9):1087-1090
将合成的两种酰胺型杯「4」聚硅氧烷(PSO-C「4」A和M-C「4」A-PSO)用作毛细管柱气相色谱固定液,考察了产的色谱特性,柱效、极性及选择性,相变温度和稳定性。结果表明,两种酰胺型杯「4」聚硅氧烷固定液具有优良的色谱性能、多环芳主一些芳香族位置异构体得到较好的分离。  相似文献   

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