Effects of humic acids on the inclusion complexation of cyclodextrins with organophosphorus pesticides

Concentration effects of humic acids on the inclusion of cyclodextrins with organophosphorus pesticides were investigated by monitoring the circular dichroism intensities induced by the pesticide inclusion.It was revealed that humic acids exert characteristic inhibition effects on the pesticide inclusion to cyclodextrins.The limiting inhibition indexes for the above effects were in correlation with the inclusion-depth parameters of the cyclodextrin-pesticide complexes.These findings were explained in terms of the complexation functions of humic materials to be effectual for solubilizing environmental chemicals such as pesticides.