Preparation and characterization of the inclusion complex of baicalein with γ-cyclodextrin: an antioxidant ability study

摘要

The formation of the complex of Baicalein with γ-cyclodextrin (γ-CD) was studied by UV-Vis absorption spectroscopy, fluorescence spectra and nuclear magnetic resonance spectroscopy (NMR) in solution. The solid inclusion complex of Baicalein with γ-CD was synthesized by the co-precipitation method. The characterization of the solid inclusion complexes have been proved by infrared spectra. The formation constant (K) of complex was determined by fluorescence method. The results suggested that in different pH solutions, γ-CD has different inclusive capacity to different forms of Baicalein. γ-CD was most suitable for inclusion in neutral media. In addition, the experimental resulted confirmed the existence of 1:1 inclusion complex of Baicalein with γ-CD. Kinetic studies of DPPH· with Baicalein and γ-CD complex were done. The results obtained indicated that the Baicalein/γ-CD complex was the most reactive form. Special configuration of complex has been proposed on NMR technique.