Liquid chromatography of phenylurea herbicides and related compounds on chemically bonded ion-exchange materials

The possibilities of using new chemically bonded anion-exchange (Silasorb DEA) and cation-exchange (Silasorb S) materials for high-performance liquid chromatography of phenylurea herbicide compounds were investigated. The columns packed with Silasorb DEA or with Silasorb S ion-exchange materials can be used for efficient separations in normal-phase systems using n-propanol-n-hexane as mobile phases. Here, specific selectivity effects for phenylurea-type herbicides can be achieved in comparison to chromatography on unmodified silica or on chemically bonded aminosilica or cyanosilica, especially with Silasorb S columns. The influence of the mobile phase composition and of the structure of phenylurea herbicides on the chromatographic behaviour on Silasorb S and Silasorb DEA columns was investigated in detail and the possibilities of separation are illustrated by several examples.