β-cyclodextrin inclusion complexes containing Citrus sinensis (L.) Osbeck essential oil: An alternative to control Aedes aegypti larvae

The development of beta-cyclodextrin (beta-CD) complexes is an interesting way for increasing the aqueous solubility of essential oils. The aim of this study was to prepare inclusion complexes of Citrus sinensis essential oil (CSEO) with beta-CD using paste complexation (with and without co-solvent) and co-precipitation methods. Additionally, the physicochemical properties of the inclusion complexes using thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were evaluated. Furthermore, CSEO content (%) and solubility of complexes were measured. The biological activity against the Aedes aegypti Linn. larvae was further evaluated. For comparison purposes, a physical mixture between beta-CD and CSEO was prepared and evaluated. Thermal analysis clearly indicated the formation of complexes by paste and co-precipitation methods. The headspace/gas chromatography quantitative analysis showed inclusions contents higher than 50%. On the other hand, the product revealed LC50 of 23.01 ppm, close to CSEO LC50 21.5 PPm. (C) 2015 Elsevier B.V. All rights reserved.