Centrifugal Thin-layer Chromatography Research Articles

Triterpenes, Sesquiterpene and Alkaloids from Meiogyne monosperma

This paper reports for the first time phytochemical study on Meiogyne monosperma (Annonaceae) which was collected from National Park, Pahang, Malaysia. The isolation and purification steps involve column chromatography, centrifugal thin layer chromatography and preparative thin layer chromatography lead to isolation of four triterpenes, lupeol, campesterol, β-sitosterol; a sesquiterpene, β-selinenol and two alkaloids, liriodenine and lanuginosine.

Extraction and Purification of Astaxanthin from Shrimp Shell with Alkaline-Organic-Solvent Method

The Alkaline-organic-solvent Method was employed to extract astaxanthin from shrimp shell in this work. The results demonstrated that the optimum extraction temperature was 20°C, the optimum ratio of extraction agent to sample is 1:3. Centrifugal thin layer chromatography was used to purify the astaxanthin and the optimum developer was petroleum, acetone and methanol (14:5:1). The FT-IR spectra and the HPLC analysis both demonstrated the purified substance was identical with standard astaxanthin and the content of astaxanthin account for 55.4%.

Radial Chromatography for the Separation of Nitroaniline Isomers

Separation techniques are usually presented in the undergraduate organic laboratory to teach students how to purify and isolate compounds. Often the concept of liquid chromatography is introduced by having students create “silica gel columns” to separate components of a reaction mixture. Although useful, column chromatography can be a laborious technique for students to perform. The separation efficiency can be compromised if students do not prepare the column correctly, and the time required to separate substances can extend beyond a typical laboratory period. Herein, the use of radial chromatography (centrifugal thin-layer chromatography) as an alternative to the traditional column chromatography technique utilized in many teaching laboratories is discussed. Radial chromatography can be used to introduce the principles that underlie liquid chromatography, with the added benefit of providing a relatively fast and highly efficient separation. An experiment for the efficient separation of a mixture contain...

Centrifugal thin-layer chromatography of alkaloids from vegetable sources using an aluminium oxide layer

Centrifugal thin-layer chromatography of alkaloids from vegetable sources using an aluminium oxide layer

Preparative separation of diastereoisomeric 2-arylpropionic acid derivatives by centrifugal thin-layer chromatography : Comparison with preparative liquid chromatography

Preparative separation of diastereoisomeric 2-arylpropionic acid derivatives by centrifugal thin-layer chromatography : Comparison with preparative liquid chromatography

Separation of natural polar substances by reversed-phase high-performance liquid chromatography, centrifugal thin-layer chromatography and droplet counter-current chromatography

Reversed-phase high-performance liquid chromatography, centrifugal thin-layer chromatography and droplet counter-current chromatography are complementary, highly efficient techniques for isolating natural, very polar, substances from plant sources. The choice of method can be made directly by a preliminary thin-layer chromatographic investigation. An application to the isolation of some new triterpenic glycosides in Passiflora quadrangularis L. is described.

Coumarins from Polygala paniculata.

From the petrol ether and chloroform extracts of POLYGALA PANICULATA L. (Polygalaceae), possessing both molluscicidal and antifungal properties, four coumarins were isolated by flash chromatography and centrifugal thin-layer chromatography. They were identified as aurapten, phebalosin, murrangatin and 7-methoxy-8-(l,4-dihydroxy-3-methyl-2-butenyl)coumarin, a new natural product. Among these compounds phebalosin showed biological activity, but proved to be very unstable in aqueous solution.

Petroporphyrins in Gaosheng crude oil

China's Gaosheng crude oil is characterized as being high in nickel and low in vanadium. Nickel porphyrins were extracted with dimetrylformamide, concentrated by absorption chromatography and demetallized with methylsulfonic acid. The concentrate of demetallized porphyrins was then separated by centrifugal thin-layer chromatography, in which DPEP, ETIO, Di-DPEP, Rhdo-ETIO, Rhdo-DPEP and Rhodo-Di-DPEP types of porphyrin were identified by mass spectrometry and UV-VIS spectroscopy. The possible geochemical pathways from DPEP to Di-DPEP and from Di-DPEP to Rhodo-DPEP series are discussed.

Parameters of preparative centrifugal thin-layer chromatography

The separation performance of preparative, centrifugal thin-layer chromatography was investigated for various flow rates and rotational speeds by means of a modified commerical instrument. High flow rates give rapid separations but require large amounts of solvent. Maximum separation (that is, greatest resolution Rs) is obtained at medium speeds and flow rates. The maximum sample size for a successful separation depends primarily on the type of substance. It varies from 10 to 1 000 mg per compound and per mm of layer thickness. Centrifugal TLC is superior to conventional “layer chromatography”. Possible improvements of the instrument are pointed out.

Rapid preparative separation of natural products by centrifugal thin-layer chromatography

Rapid preparative separation of natural products by centrifugal thin-layer chromatography