Investigation of homologous series of fatty acids by TLC. Part IV. Separation on RP18 plates with ternary mobile phases

Abstract

Fatty acids from heptanoic to eicosanoic have been separated on RP-18 HPTLC plates, with and without concentrating zone, with methanol-ethanol-water, methanol- n -propanol-water, and ethanol- n -propanol-water mixtures as mobile phases. The best chromatographic conditions for separation of the fatty acids were RP-18 plates without concentrating zone and methanol-ethanol-water, 45 + 45 + 10 ( v/v as mobile phase, and RP-18 plates with concentrating zone and methanol-ethanol-water or methanol- n -propanol-water, 45 + 45 + 10 ( v/v ), as mobile phases. Taking into consideration previous results of our research we can state that the best RP HPTLC separations of fatty acids have been obtained on RP-18 plates without concentrating zone and with methanol-water, 95 + 5 ( v/v ), as mobile phase, and on RP-18 plates with concentrating zone with methanol-water, 90 + 10 or 95 + 5, 100% methanol, ethanol-water, 95 + 5 or 90 + 10 ( v/v ), or methanol-ethanol-water or methanol- n -propanol-water, 45 + 45 + 10 ( v/v ), a...