The formation of an amorphous composite between flavonoid compounds: Enhanced solubility in both oil components and aqueous media

Abstract

In this study, the formation of naringenin (NRG) amorphous composite using coformer candidates of nine selected flavonoids was investigated. The screening test showed that hesperetin (HPT) is an excellent potential coformer. The melt-quenched particles (MQPs) of NRG/HPT (molar ratio of 3/1 to 1/3) were prepared by melt-quenching method. MQPs of NRG/HPT showed the hallow-pattern in any combination ratio in powder X-ray diffraction. MQPs of NRG/HPT (1/1) showed the highest physical stability without recrystallization of NRG and HPT upon storage. Conversely, other MQPs showed recrystallization from the compound with a higher molar ratio, implying the stoichiometric relationship between NRG and HPT at a molar ratio of 1/1. The MQPs of NRG/HPT (1/1) showed significantly improved dissolution properties of both NRG and HPT in aqueous media. In addition, the MQPs of NRG/HPT (1/1) enhanced the solubility of both NRG and HPT even in oil components. Their solubility from the MQPs of NRG/HPT (1/1) increased 5-times compared to untreated compound powder in oil components. These results showed that an amorphous composite of NRG/HPT (1/1) enhances the physical stability and solubility of both NRG and HPT.