A THIN-LAYER CHROMATOGRAPHIC METHOD FOR DETERMINATION OF PLANT PIGMENTS IN SEA WATER AND CULTURES

A combined thin-layer Chromatographic-reflection densitometric procedure is described for the determination of chlorophylls and carotenoid pigments in marine particulate matter. A comparison of various methods of filtration showed that optimum recoveries of plant pigments are obtained with Whatman GF/C glass fibre filters covered with a layer of magnesium carbonate. Plant pigments are extracted by means of acetone and methanol and the combined extracts are evaporated under reduced pressure. Thin-layer chromatography is carried out on silica gel G. Chlorophyll c remains at the starting point and is separated from the origin spot by a subsequent development with a more polar solvent mixture. The separated pigments are determined on the plate by photodensitometry in the reflectance mode. Chlorophylls a, b and c, carotene, many of the individual xanthophylls and certain degradation products of the chlorophylls can be determined. The complete analysis can be performed in under 1 h. The sensitivity of the method for chlorophyll a is ca. 0.12 μg and the precision for most pigments is ±5% or better at the 0.5-μg level. © 1969.