two dimensional thin layer chromatography on polyamide sheets is a useful method for identification of pth-amino acids which have very close rf-values. the solvent systems described here are particularly effective and have an edge over other solvent systems used for the separation of pth-amino acids. the solvent systems provide a clear separation of all pth-amono acids except lle / leu in a rel...

Separation of the amino acids in urine by use of thin-layer chromatography (TLC) has hitherto required that the specimen be first desalted and then chromatographed in two dimensions with at least two pairs of developing solvent systems. We wished to simplify both steps. The customary method of desalting on a column is replaced by desalting on a plate that supports a strongly acid cation-exchang...

A simple and rapid method for screening of drugs in health foods using 2-dimensional TLC was established. The development systems were: (1) ethyl acetate/methanol/28% ammonia (85:10:5), (2) cyclohexane/toluene/diethyl amine (65:25:10), (3) methanol and (4) ethyl acetate/methanol/25% ammonia (85:10:5). System (1) and (2) were run as 2-dimensional high-performance TLC, and System (3) and (4) were...

An automated one- or two-dimensional TLC tank is described. The solvent front is monitored by a photocell or recycling timers.

In the previous paper from this series, we proposed mass spectrometric fingerprinting of complex botanical samples upon the examples of the pharmacologically important phenolic acids and flavonoids selectively extracted from Salvia lavandulifolia. In this study, we explore fingerprinting efficiency with a novel two-dimensional analytical system composed of the reversed-phase thin-layer chromato...