RETENTION OF 4-CYANOPHENYL HERBICIDES ON WATER-INSOLUBLE BETA-CYCLODEXTRIN SUPPORT

The retention of eight cyanophenyl herbicides on water-insoluble beta-cyclodextrin polymer beads (BCDP) was determined by thin-layer chromatography using BCDP as stationary phase. The effects of pH, salt concentration in the aqueous eluent systems and the various physico-chemical parameters of herbicides on the herbicide-BCDP interaction were calculated by using principal component analysis. The pH of the eluent exerted a higher influence than the salt concentration on the retention of herbicides. The hydrophobicity and steric characteristics of solutes had the highest impact on their retention behaviour. Calculations revealed that BCDP showed a mixed retention mechanism and hydrophobic and hydrophilic forces in addition to steric parameters are involved in the interaction.