Simple method for the quantitative analysis of tetracyclines by direct fluorimetry after thin-layer chromatography on cellulose plates.

A thin-layer chromatographic method is described in which tetracyclines are separated on a cellulose layer by development with aqueous solutions of certain salts (magnesium, calcium, barium and zinc chloride). The spots exhibit good fluorescence in UV light, allowing ready detection without the necessity for treatment with any reagents. This fluorescence can be used for the direct photometric determination of the tetracyclines with good accuracy.