Improvement in solubility and dissolution rate of flavonoids by complexation with beta-cyclodextrin

Area of Science:

• Pharmacology and Pharmaceutical Sciences
• Materials Science

Background:

• Hesperetin and naringenin are flavonoids with potential therapeutic benefits but poor water solubility.
• Beta-cyclodextrin is a cyclic oligosaccharide known for its ability to form inclusion complexes and enhance drug solubility.

Purpose of the Study:

• To investigate the formation and characterization of beta-cyclodextrin inclusion complexes with hesperetin and naringenin.
• To evaluate the impact of beta-cyclodextrin on the solubility, stability, and dissolution properties of these flavonoids.

Main Methods:

• Solubility studies were conducted at varying beta-cyclodextrin concentrations and temperatures.
• Stability constants were determined using the Higuchi and Connors solubility method.
• Thermodynamic parameters for complex formation were calculated.
• Solid inclusion complexes were prepared at a 1:1 molar ratio.
• Dissolution behavior of the complexes was examined at different pH values.

Main Results:

• Solubility of hesperetin and naringenin increased with rising beta-cyclodextrin concentration and temperature.
• Stability constants and thermodynamic parameters indicated favorable complex formation in aqueous solution.
• The solid 1:1 complexes exhibited distinct dissolution profiles at varying pH levels.

Conclusions:

• Beta-cyclodextrin inclusion complexation significantly improves the solubility and dissolution characteristics of hesperetin and naringenin.
• These findings suggest that beta-cyclodextrin can be a viable strategy for developing effective pharmaceutical formulations of these flavonoids.