Advantages of biocides: β-cyclodextrin inclusion complexes against active components for pesticide industry

In this paper, the stability at storage conditions of inclusion complexes formed by the biocides: the bendiocarb carbamate, nicotinoid and pyrethroid families, the pyperonyl butoxide synergist and the tebuconazole fungicide, with beta-cyclodextrin (CD) were studied. These complexes, in solid state and aqueous suspension, were exposed to normal atmospheric conditions, as well as under accelerated and stress test conditions. Results obtained were compared with those corresponding to pure active product and their solutions. Moreover, water solubility of the inclusion complexes synthesized in our laboratory was checked. Differential scanning calorimetry (DSC) and Uv-vis spectrophotometry were used as the analytical techniques for these studies. Microencapsulation of biocides with CD not only showed the enhancement of aqueous solubility and stability (referred to the time the biocide remains in the cavity of CD) but also produced the solidification of liquid biocides. Therefore, contrary to free biocides, CD inclusion complexes provide three important advantages to be taken into account for the future industrial production of biocide formulations applied to indoor pest control.