径向展开薄层色谱法分离生物碱及其分离效能

径向展开薄层色谱法是一种将样品由中心沿径向向外展开的简便、快速、高效的色谱方法。该文组装了简单的径向展开薄层色谱装置,并建立了朱砂安神丸的径向展开薄层色谱检测法,对其中的生物碱成分进行分离,研究了径向展开薄层色谱的分离特性。从薄层色谱基础理论出发,对径向展开薄层色谱和一般薄层色谱的分离效能进行了比对研究,设计试验进行计算和求解。证明了径向展开薄层色谱法更快、更高效、更经济,适用于生物碱等高极性样品分离。探索了径向展开薄层色谱法高分离效率的理论根源,这一研究思路也为理论创新提供了新的方法和思路。     

聚谷氨酸苄酯掺杂硅胶用于拆分氧氟沙星对映体

通过将聚谷氨酸苄酯（PBLG）掺杂在硅胶中,建立了一种分离手性物质氧氟沙星对映体的方法。以壳聚糖为引发剂,利用开环聚合方法合成了PBLG。将PBLG掺杂在硅胶G中制备薄层色谱板,实现了对氧氟沙星外消旋体的拆分。考察了展开溶剂体系、不同比例溶剂、展开温度和展开时间对手性拆分氧氟沙星对映异构体的影响。结果表明,该薄层色谱板拆分氧氟沙星对映异构体的最佳条件为：0.5 g PBLG掺杂在2 g硅胶G中,以乙腈-甲醇（V/V=2∶1）混合溶剂为展开体系,35℃下展开30 min。氧氟沙星对映体单体在薄层色谱板上的手性分离因子（α）范围为2.62～6.12,实现了基线分离。     

自制高效薄层预制板及其在分离天然产物中的应用

七十年代以来,在色谱领域里继高效液相色谱之后又发展了高效薄层色谱。由于双波长薄层色谱扫描仪的出现,使高效薄层方法在天然产物的分离鉴定方面应用更为广泛。高效薄层色谱(High PerformanceTLC)的优点是加样量少,快速、分辨力高、检出限度可达毫微克至微微克水平。一般薄层色谱的塔板高为30微米,而高效薄层可低至12微米,这样在展开距离为3—7厘米时,塔板数可达数千之多,因此分离效能大为提高。一般薄层展开10—15     

圆形薄层色谱分离铜和镍——介绍一个分离实验

薄层色谱用于分离痕量金属比纸色谱所需的展开时间更短,尤其是圆形薄层色谱,具有快速、简便、灵敏度高对设备要求低的优点。本实验通过对用圆形薄层色谱法分离铜、镍的实验条件的试验（薄层板活化时间、活化湿度展,开剂组成等）,从而确定实验步骤,以获得最佳分离效果。     

薄层色谱实验的改进及教学探讨

以对二甲氨基偶氮苯和反式偶氮苯的混合物作测试样,在薄层板上点样后于单一溶剂和不同比例的混合溶剂中展开,考察样品极性和溶剂极性变化对薄层色谱分离效果的影响;以乙酰苯胺和苯甲酰胺作测试样,点样展开后分别在紫外灯下和碘缸中显色,让学生能够熟练掌握一些常用的薄层色谱显色方法;对实验过程中的一些关键性问题,如物质极性与展开剂的选择、显色方法和分离效果等进行了教学方法探讨。     

计算机辅助一清片径向展开薄层色谱定性与定量方法初探

径向薄层色谱法（RTLC）是一种将样品呈圆形或环状点样,然后将展开剂从中心向外沿径向输送的薄层色谱方法。在一定的展开距离内,RTLC是一种分离快速、扩散小、不拖尾的高效分离和半制备方法。目前关于RTLC分离的报道较多,但对RTLC定性和定量的报道较少。该文采用自编程方式结合图像处理软件,实现RTLC图像数字化处理,形成RTLC数字化图谱,并对RTLC进行定性与定量方法学验证,建立了一清片RTLC定性与定量方法。辅助计算机技术,对一清片径向展开薄层色谱定性与定量方法进行初探。结果表明,该方法用于RTLC定性的可靠度较好,但用于RTLC的定量,仍有不足之处,这可能与实验环境条件等有关。通过搭载更好的分离和数据采集设备,RTLC会有适合的用武之地。计算机图像处理和自编程方法的结合给了RTLC和其他一些分析相关的技术广阔的发展前景。相信未来在计算机技术的辅助下,薄层色谱技术会迈上一个新的台阶。     

外标原位扫描定量双向薄层色谱测定氨基酸

本文在利用微晶纤维素—硅胶G薄层板对氨基酸获得了良好的分离基础上,进一步探索了用亚双向分离外标原位扫描定量测定双向薄层色谱上的氨基酸含量的可行性。结果表明此方法较方便可靠,重复性好。(亚双向分离外标校正,就是外标混合液点,一向充分展开分离,而另一向只展开短距离,约1厘米左右)。     

二维薄层色谱板的研制

二维薄层色谱板是在一块板上同时涂布不同吸附性能——正相和反相两种吸附剂的一种高性能的薄板,在极性和非极性溶剂中依次展开。由于它能获得更多的分离信息,可使定量分离的峰的数目大为增加,适合于分离复杂的混合物。二维薄层色谱板的概念是G.Guiocholl首先提出的。用二维技术进行复杂物质的分离,国外已有报道,国内尚末见报道。 制备分离性能良好的二维薄层色谱板的首要问题是要能分别制出正相及反相高效薄层色谱板。另一个问题就是如何把两种不同性能吸附剂很好地衔接在同一块板上     

薄层电色谱技术的研究进展

薄层电色谱技术将电场力的作用引入薄层色谱的分离过程中,具有分离时间短、分辨率高等特点,将可能在物质分析分离中发挥重要作用.本文介绍了薄层电色谱仪器装置的设计、固定相和流动相的类型、薄层电色谱的应用等内容,总结了目前的研究工作中存在的主要问题,并展望了该技术未来的发展趋势,还介绍了与薄层电色谱有相似的毛细管电色谱和自由流电泳技术.引文献50篇.     

用薄层色谱扫描仪对农药的定性和定量研究——Ⅰ.22种农药在硅胶薄层上的定性研究

薄层色谱能快速分离微量混合物,并直接在薄层板上对被分离的物质进行定性及定量测定。因此,目前该法已成为应用最广泛的分离分析方法之一。但是薄层色谱的定性鉴定至今仍采用R_F值或R_M值,而由于许多物质在一些溶剂系统中的R_F值往往是相同的,有时甚至经多种溶剂系统展开后其R_F值仍无很大差异,这就给在薄层上对物质的定性鉴     

Planar chromatography at the turn of the century.

An overview of the state-of-the-art of modern thin-layer chromatography (planar chromatography) is presented with emphasis on the complementary features of thin-layer and column liquid chromatographic separations. The reasons for selecting thin-layer chromatography for a particular analysis are identified by its attributes: a disposable stationary phase; simultaneous parallel separations; static detection free of time constraints; storage device for chromatographic information; all sample components are observed in the chromatogram. Future prospects for improved separation performance in TLC using zone refocusing, forced flow and electroosmotic flow methods are discussed as well as increasing zone capacity by using two-dimensional development and coupling to column chromatographic methods. Advances in coupling thin-layer chromatography with spectroscopic methods for structural elucidation are also considered. Finally, some predictions are made for how thin-layer chromatography will be practiced in the future.     

Processes dominating forced-flow thin-layer chromatography

Summary The effect of the vapor phase and other special influences on thin-layer chromatography have been investigated. Comparisons were made of the relationships of time vs. developing distance and flow rate vs. efficiency using a planar arrangement of the thin-layer. Covering the layer facilitates the reproducibility and of the migration front but the most effective optimization step for thin-layer chromatography is provided by forced-flow of the mobile phase. It is suggested that planar chromatography with a covered sorbent layer and using a pressurised solvent stream should be calledforced-flow thin-layer chromtatography.     

Experience with Quantitative Thin-Layer Chromatography in the Analysis of Drugs in Plasma

Abstract

A survey is presented concerning the possible techniques of quantitative thin-layer chromatography. Most of the possibilities mentioned have been used successfully in our laboratory for the determination of drugs and metabolites in plasma. With respect to our own experience, the advantages and disadvantages of quantitative thin-layer chromatography are discussed.

Although gas chromatography and high-performance liquid chromatography are more popular, quantitative thin-layer chromatography has a high potential in the analysis of drugs in samples of biological origin and should not be neglected in the development of an assay.     

Chromatographic analysis of blood lipids. Comparison between gas chromatography and thin-layer chromatography with flame ionization detection

Intact human blood plasma lipids of different composition were analyzed by gas chromatography and thin-layer chromatography with flame ionization detection. The reproducibility of the results obtained by gas and thin-layer chromatography was compared. The main advantages and disadvantages of both methods for lipid analysis are discussed. Generally, the variability of the results measured by thin-layer chromatography in series and from day to day was greater than that obtained by gas chromatography.     

薄层层析法在表面活性剂检测和分析中的应用

薄层层析（ＴＬＣ）是一种简便的分离分析方法。适用于许多有机化合物的分离,精制,定性和定量分析,也是表面活性剂分析中的重要手段之一。文中简述了薄层层析的测试方法、条件选择和发展趋势,并对ＴＬＣ在表面活性剂检测和分析中的应用作了具体阐述。     

Separation of androsterone from epiandrosterone, and dehydroepiandrosterone from its 3-hydroxy epimer by thin-layer chromatography.

The application of thin-layer chromatography to the separation of 13 steroids, including androstanes, 4-androstenes and 5-androstenes, using silica gel and 1,2-propanediol-impregnated cellulose is described. After group-wise separation of various C19 steroids on silica gel, the 3-hydroxy epimers of 5alpha-androstanes and 5-androstenes can be separated by thin-layer chromatography on impregnated cellulose plates. The chromatographic procedure is rapid and makes the prior formation of steroid derivatives unnecessary.     

Determination of organophosphorus pesticides by thin-layer chromatography

Analysis for 13 common organophosphorus pesticides by thin-layer chromatography is described; 17 solvent systems were examined. With channel thin-layer chromatography, linear calibration graphs were obtained for the range 1-10 mug.     

Capillary thin-layer chromatography of antibacterial nitrofuran derivatives

Russian Journal of Applied Chemistry - A new version of thin-layer chromatography, capillary thin-layer chromatography, which is similar to traditional planar chromatography in the idea of...     

Identification of 9-hydroxylamine-1,2,3,4-tetrahydroacridine as a hepatic microsomal metabolite of tacrine by high-performance liquid chromatography and electrochemistry

Amperometric detection using a dual-electrode thin-layer cell in the series configuration can aid in the identification of unknown components in complicated samples by voltammetric characterization. This is shown by studying the metabolism of tacrine by rat hepatic microsomes using high-performance liquid chromatography with electrochemical detection. The major metabolite detected in microsomal incubations did not co-elute with any standard acridine available and was produced in too small a quantity for mass spectral characterization. Tentative identification of this metabolite as 9-hydroxylamine-1,2,3,4-tetrahydroacridine was made by electrochemical characterization. The electrochemistry of the metabolite was compared to that of the hydroxylamine produced and studied by cyclic voltammetry.     

N-terminal sequence analysis of peptides by means of Edman-Abbaus: a combination of application of their directions and of the subraction method

A particularly reliable N-terminal sequence analysis of peptides can be achieved by the following combined application of Edman's phenylisothiocyanate technique, and thin-layer chromatography. The N-terminal amino acids acids split off are identified as phenylthiohydantoin- and dimethylaminonaphthalensulfonyl-derivatives; additionally, quantitative analysis of amino acids using thin-layer chromatography is carried out before and after each degradation step. The applicability of this combined procedure is demonstrated in the case of a nonapeptide.