Coencapsulation of Ferulic and Gallic acid in hp-b-cyclodextrin

The complexes formed by two polyphenols, trans-Ferulic acid (FA) and Gallic acid (GA) with 2-hydroxypropyl-b-cyclodextrin (HPβCD), by the spray-drying method, were studied. Encapsulation-efficiencies (EE) of the complexes prepared were evaluated by HPLC. In the case of co-encapsulation, the EE of GA was lowered, whereas that of FA was almost stable, indicating a possible antagonistic relationship between the two phenols for the HPβCD cavity. The physicochemical characterization of the complexes was carried out by Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). SEM observations revealed that the coencapsulated phenolic complex resulted in a more rounded shape outer surfaces of HPβCD than when encapsulated separately. FT-IR and DSC data indicated that the two polyphenols exhibit a possible interaction in the coencapsulated complex. The complexes showed no loss of their ability to scavenge DPPH radical relatively to the single agent at the concentrations used.